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1 /*
2  * Copyright (C) 2010 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 /**
18  * @addtogroup Input
19  * @{
20  */
21 
22 /**
23  * @file input.h
24  */
25 
26 #ifndef _ANDROID_INPUT_H
27 #define _ANDROID_INPUT_H
28 
29 /******************************************************************
30  *
31  * IMPORTANT NOTICE:
32  *
33  *   This file is part of Android's set of stable system headers
34  *   exposed by the Android NDK (Native Development Kit).
35  *
36  *   Third-party source AND binary code relies on the definitions
37  *   here to be FROZEN ON ALL UPCOMING PLATFORM RELEASES.
38  *
39  *   - DO NOT MODIFY ENUMS (EXCEPT IF YOU ADD NEW 32-BIT VALUES)
40  *   - DO NOT MODIFY CONSTANTS OR FUNCTIONAL MACROS
41  *   - DO NOT CHANGE THE SIGNATURE OF FUNCTIONS IN ANY WAY
42  *   - DO NOT CHANGE THE LAYOUT OR SIZE OF STRUCTURES
43  */
44 
45 /*
46  * Structures and functions to receive and process input events in
47  * native code.
48  *
49  * NOTE: These functions MUST be implemented by /system/lib/libui.so
50  */
51 
52 #include <stdint.h>
53 #include <sys/types.h>
54 #include <android/keycodes.h>
55 #include <android/looper.h>
56 
57 #ifdef __cplusplus
58 extern "C" {
59 #endif
60 
61 /**
62  * Key states (may be returned by queries about the current state of a
63  * particular key code, scan code or switch).
64  */
65 enum {
66     /** The key state is unknown or the requested key itself is not supported. */
67     AKEY_STATE_UNKNOWN = -1,
68 
69     /** The key is up. */
70     AKEY_STATE_UP = 0,
71 
72     /** The key is down. */
73     AKEY_STATE_DOWN = 1,
74 
75     /** The key is down but is a virtual key press that is being emulated by the system. */
76     AKEY_STATE_VIRTUAL = 2
77 };
78 
79 /**
80  * Meta key / modifer state.
81  */
82 enum {
83     /** No meta keys are pressed. */
84     AMETA_NONE = 0,
85 
86     /** This mask is used to check whether one of the ALT meta keys is pressed. */
87     AMETA_ALT_ON = 0x02,
88 
89     /** This mask is used to check whether the left ALT meta key is pressed. */
90     AMETA_ALT_LEFT_ON = 0x10,
91 
92     /** This mask is used to check whether the right ALT meta key is pressed. */
93     AMETA_ALT_RIGHT_ON = 0x20,
94 
95     /** This mask is used to check whether one of the SHIFT meta keys is pressed. */
96     AMETA_SHIFT_ON = 0x01,
97 
98     /** This mask is used to check whether the left SHIFT meta key is pressed. */
99     AMETA_SHIFT_LEFT_ON = 0x40,
100 
101     /** This mask is used to check whether the right SHIFT meta key is pressed. */
102     AMETA_SHIFT_RIGHT_ON = 0x80,
103 
104     /** This mask is used to check whether the SYM meta key is pressed. */
105     AMETA_SYM_ON = 0x04,
106 
107     /** This mask is used to check whether the FUNCTION meta key is pressed. */
108     AMETA_FUNCTION_ON = 0x08,
109 
110     /** This mask is used to check whether one of the CTRL meta keys is pressed. */
111     AMETA_CTRL_ON = 0x1000,
112 
113     /** This mask is used to check whether the left CTRL meta key is pressed. */
114     AMETA_CTRL_LEFT_ON = 0x2000,
115 
116     /** This mask is used to check whether the right CTRL meta key is pressed. */
117     AMETA_CTRL_RIGHT_ON = 0x4000,
118 
119     /** This mask is used to check whether one of the META meta keys is pressed. */
120     AMETA_META_ON = 0x10000,
121 
122     /** This mask is used to check whether the left META meta key is pressed. */
123     AMETA_META_LEFT_ON = 0x20000,
124 
125     /** This mask is used to check whether the right META meta key is pressed. */
126     AMETA_META_RIGHT_ON = 0x40000,
127 
128     /** This mask is used to check whether the CAPS LOCK meta key is on. */
129     AMETA_CAPS_LOCK_ON = 0x100000,
130 
131     /** This mask is used to check whether the NUM LOCK meta key is on. */
132     AMETA_NUM_LOCK_ON = 0x200000,
133 
134     /** This mask is used to check whether the SCROLL LOCK meta key is on. */
135     AMETA_SCROLL_LOCK_ON = 0x400000,
136 };
137 
138 struct AInputEvent;
139 /**
140  * Input events.
141  *
142  * Input events are opaque structures.  Use the provided accessors functions to
143  * read their properties.
144  */
145 typedef struct AInputEvent AInputEvent;
146 
147 /**
148  * Input event types.
149  */
150 enum {
151     /** Indicates that the input event is a key event. */
152     AINPUT_EVENT_TYPE_KEY = 1,
153 
154     /** Indicates that the input event is a motion event. */
155     AINPUT_EVENT_TYPE_MOTION = 2
156 };
157 
158 /**
159  * Key event actions.
160  */
161 enum {
162     /** The key has been pressed down. */
163     AKEY_EVENT_ACTION_DOWN = 0,
164 
165     /** The key has been released. */
166     AKEY_EVENT_ACTION_UP = 1,
167 
168     /**
169      * Multiple duplicate key events have occurred in a row, or a
170      * complex string is being delivered.  The repeat_count property
171      * of the key event contains the number of times the given key
172      * code should be executed.
173      */
174     AKEY_EVENT_ACTION_MULTIPLE = 2
175 };
176 
177 /**
178  * Key event flags.
179  */
180 enum {
181     /** This mask is set if the device woke because of this key event. */
182     AKEY_EVENT_FLAG_WOKE_HERE = 0x1,
183 
184     /** This mask is set if the key event was generated by a software keyboard. */
185     AKEY_EVENT_FLAG_SOFT_KEYBOARD = 0x2,
186 
187     /** This mask is set if we don't want the key event to cause us to leave touch mode. */
188     AKEY_EVENT_FLAG_KEEP_TOUCH_MODE = 0x4,
189 
190     /**
191      * This mask is set if an event was known to come from a trusted
192      * part of the system.  That is, the event is known to come from
193      * the user, and could not have been spoofed by a third party
194      * component.
195      */
196     AKEY_EVENT_FLAG_FROM_SYSTEM = 0x8,
197 
198     /**
199      * This mask is used for compatibility, to identify enter keys that are
200      * coming from an IME whose enter key has been auto-labelled "next" or
201      * "done".  This allows TextView to dispatch these as normal enter keys
202      * for old applications, but still do the appropriate action when
203      * receiving them.
204      */
205     AKEY_EVENT_FLAG_EDITOR_ACTION = 0x10,
206 
207     /**
208      * When associated with up key events, this indicates that the key press
209      * has been canceled.  Typically this is used with virtual touch screen
210      * keys, where the user can slide from the virtual key area on to the
211      * display: in that case, the application will receive a canceled up
212      * event and should not perform the action normally associated with the
213      * key.  Note that for this to work, the application can not perform an
214      * action for a key until it receives an up or the long press timeout has
215      * expired.
216      */
217     AKEY_EVENT_FLAG_CANCELED = 0x20,
218 
219     /**
220      * This key event was generated by a virtual (on-screen) hard key area.
221      * Typically this is an area of the touchscreen, outside of the regular
222      * display, dedicated to "hardware" buttons.
223      */
224     AKEY_EVENT_FLAG_VIRTUAL_HARD_KEY = 0x40,
225 
226     /**
227      * This flag is set for the first key repeat that occurs after the
228      * long press timeout.
229      */
230     AKEY_EVENT_FLAG_LONG_PRESS = 0x80,
231 
232     /**
233      * Set when a key event has AKEY_EVENT_FLAG_CANCELED set because a long
234      * press action was executed while it was down.
235      */
236     AKEY_EVENT_FLAG_CANCELED_LONG_PRESS = 0x100,
237 
238     /**
239      * Set for AKEY_EVENT_ACTION_UP when this event's key code is still being
240      * tracked from its initial down.  That is, somebody requested that tracking
241      * started on the key down and a long press has not caused
242      * the tracking to be canceled.
243      */
244     AKEY_EVENT_FLAG_TRACKING = 0x200,
245 
246     /**
247      * Set when a key event has been synthesized to implement default behavior
248      * for an event that the application did not handle.
249      * Fallback key events are generated by unhandled trackball motions
250      * (to emulate a directional keypad) and by certain unhandled key presses
251      * that are declared in the key map (such as special function numeric keypad
252      * keys when numlock is off).
253      */
254     AKEY_EVENT_FLAG_FALLBACK = 0x400,
255 };
256 
257 /**
258  * Bit shift for the action bits holding the pointer index as
259  * defined by AMOTION_EVENT_ACTION_POINTER_INDEX_MASK.
260  */
261 #define AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT 8
262 
263 /** Motion event actions */
264 enum {
265     /** Bit mask of the parts of the action code that are the action itself. */
266     AMOTION_EVENT_ACTION_MASK = 0xff,
267 
268     /**
269      * Bits in the action code that represent a pointer index, used with
270      * AMOTION_EVENT_ACTION_POINTER_DOWN and AMOTION_EVENT_ACTION_POINTER_UP.  Shifting
271      * down by AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT provides the actual pointer
272      * index where the data for the pointer going up or down can be found.
273      */
274     AMOTION_EVENT_ACTION_POINTER_INDEX_MASK  = 0xff00,
275 
276     /** A pressed gesture has started, the motion contains the initial starting location. */
277     AMOTION_EVENT_ACTION_DOWN = 0,
278 
279     /**
280      * A pressed gesture has finished, the motion contains the final release location
281      * as well as any intermediate points since the last down or move event.
282      */
283     AMOTION_EVENT_ACTION_UP = 1,
284 
285     /**
286      * A change has happened during a press gesture (between AMOTION_EVENT_ACTION_DOWN and
287      * AMOTION_EVENT_ACTION_UP).  The motion contains the most recent point, as well as
288      * any intermediate points since the last down or move event.
289      */
290     AMOTION_EVENT_ACTION_MOVE = 2,
291 
292     /**
293      * The current gesture has been aborted.
294      * You will not receive any more points in it.  You should treat this as
295      * an up event, but not perform any action that you normally would.
296      */
297     AMOTION_EVENT_ACTION_CANCEL = 3,
298 
299     /**
300      * A movement has happened outside of the normal bounds of the UI element.
301      * This does not provide a full gesture, but only the initial location of the movement/touch.
302      */
303     AMOTION_EVENT_ACTION_OUTSIDE = 4,
304 
305     /**
306      * A non-primary pointer has gone down.
307      * The bits in AMOTION_EVENT_ACTION_POINTER_INDEX_MASK indicate which pointer changed.
308      */
309     AMOTION_EVENT_ACTION_POINTER_DOWN = 5,
310 
311     /**
312      * A non-primary pointer has gone up.
313      * The bits in AMOTION_EVENT_ACTION_POINTER_INDEX_MASK indicate which pointer changed.
314      */
315     AMOTION_EVENT_ACTION_POINTER_UP = 6,
316 
317     /**
318      * A change happened but the pointer is not down (unlike AMOTION_EVENT_ACTION_MOVE).
319      * The motion contains the most recent point, as well as any intermediate points since
320      * the last hover move event.
321      */
322     AMOTION_EVENT_ACTION_HOVER_MOVE = 7,
323 
324     /**
325      * The motion event contains relative vertical and/or horizontal scroll offsets.
326      * Use getAxisValue to retrieve the information from AMOTION_EVENT_AXIS_VSCROLL
327      * and AMOTION_EVENT_AXIS_HSCROLL.
328      * The pointer may or may not be down when this event is dispatched.
329      * This action is always delivered to the winder under the pointer, which
330      * may not be the window currently touched.
331      */
332     AMOTION_EVENT_ACTION_SCROLL = 8,
333 
334     /** The pointer is not down but has entered the boundaries of a window or view. */
335     AMOTION_EVENT_ACTION_HOVER_ENTER = 9,
336 
337     /** The pointer is not down but has exited the boundaries of a window or view. */
338     AMOTION_EVENT_ACTION_HOVER_EXIT = 10,
339 
340     /* One or more buttons have been pressed. */
341     AMOTION_EVENT_ACTION_BUTTON_PRESS = 11,
342 
343     /* One or more buttons have been released. */
344     AMOTION_EVENT_ACTION_BUTTON_RELEASE = 12,
345 };
346 
347 /**
348  * Motion event flags.
349  */
350 enum {
351     /**
352      * This flag indicates that the window that received this motion event is partly
353      * or wholly obscured by another visible window above it.  This flag is set to true
354      * even if the event did not directly pass through the obscured area.
355      * A security sensitive application can check this flag to identify situations in which
356      * a malicious application may have covered up part of its content for the purpose
357      * of misleading the user or hijacking touches.  An appropriate response might be
358      * to drop the suspect touches or to take additional precautions to confirm the user's
359      * actual intent.
360      */
361     AMOTION_EVENT_FLAG_WINDOW_IS_OBSCURED = 0x1,
362 };
363 
364 /**
365  * Motion event edge touch flags.
366  */
367 enum {
368     /** No edges intersected. */
369     AMOTION_EVENT_EDGE_FLAG_NONE = 0,
370 
371     /** Flag indicating the motion event intersected the top edge of the screen. */
372     AMOTION_EVENT_EDGE_FLAG_TOP = 0x01,
373 
374     /** Flag indicating the motion event intersected the bottom edge of the screen. */
375     AMOTION_EVENT_EDGE_FLAG_BOTTOM = 0x02,
376 
377     /** Flag indicating the motion event intersected the left edge of the screen. */
378     AMOTION_EVENT_EDGE_FLAG_LEFT = 0x04,
379 
380     /** Flag indicating the motion event intersected the right edge of the screen. */
381     AMOTION_EVENT_EDGE_FLAG_RIGHT = 0x08
382 };
383 
384 /**
385  * Constants that identify each individual axis of a motion event.
386  * @anchor AMOTION_EVENT_AXIS
387  */
388 enum {
389     /**
390      * Axis constant: X axis of a motion event.
391      *
392      * - For a touch screen, reports the absolute X screen position of the center of
393      * the touch contact area.  The units are display pixels.
394      * - For a touch pad, reports the absolute X surface position of the center of the touch
395      * contact area. The units are device-dependent.
396      * - For a mouse, reports the absolute X screen position of the mouse pointer.
397      * The units are display pixels.
398      * - For a trackball, reports the relative horizontal displacement of the trackball.
399      * The value is normalized to a range from -1.0 (left) to 1.0 (right).
400      * - For a joystick, reports the absolute X position of the joystick.
401      * The value is normalized to a range from -1.0 (left) to 1.0 (right).
402      */
403     AMOTION_EVENT_AXIS_X = 0,
404     /**
405      * Axis constant: Y axis of a motion event.
406      *
407      * - For a touch screen, reports the absolute Y screen position of the center of
408      * the touch contact area.  The units are display pixels.
409      * - For a touch pad, reports the absolute Y surface position of the center of the touch
410      * contact area. The units are device-dependent.
411      * - For a mouse, reports the absolute Y screen position of the mouse pointer.
412      * The units are display pixels.
413      * - For a trackball, reports the relative vertical displacement of the trackball.
414      * The value is normalized to a range from -1.0 (up) to 1.0 (down).
415      * - For a joystick, reports the absolute Y position of the joystick.
416      * The value is normalized to a range from -1.0 (up or far) to 1.0 (down or near).
417      */
418     AMOTION_EVENT_AXIS_Y = 1,
419     /**
420      * Axis constant: Pressure axis of a motion event.
421      *
422      * - For a touch screen or touch pad, reports the approximate pressure applied to the surface
423      * by a finger or other tool.  The value is normalized to a range from
424      * 0 (no pressure at all) to 1 (normal pressure), although values higher than 1
425      * may be generated depending on the calibration of the input device.
426      * - For a trackball, the value is set to 1 if the trackball button is pressed
427      * or 0 otherwise.
428      * - For a mouse, the value is set to 1 if the primary mouse button is pressed
429      * or 0 otherwise.
430      */
431     AMOTION_EVENT_AXIS_PRESSURE = 2,
432     /**
433      * Axis constant: Size axis of a motion event.
434      *
435      * - For a touch screen or touch pad, reports the approximate size of the contact area in
436      * relation to the maximum detectable size for the device.  The value is normalized
437      * to a range from 0 (smallest detectable size) to 1 (largest detectable size),
438      * although it is not a linear scale. This value is of limited use.
439      * To obtain calibrated size information, see
440      * {@link AMOTION_EVENT_AXIS_TOUCH_MAJOR} or {@link AMOTION_EVENT_AXIS_TOOL_MAJOR}.
441      */
442     AMOTION_EVENT_AXIS_SIZE = 3,
443     /**
444      * Axis constant: TouchMajor axis of a motion event.
445      *
446      * - For a touch screen, reports the length of the major axis of an ellipse that
447      * represents the touch area at the point of contact.
448      * The units are display pixels.
449      * - For a touch pad, reports the length of the major axis of an ellipse that
450      * represents the touch area at the point of contact.
451      * The units are device-dependent.
452      */
453     AMOTION_EVENT_AXIS_TOUCH_MAJOR = 4,
454     /**
455      * Axis constant: TouchMinor axis of a motion event.
456      *
457      * - For a touch screen, reports the length of the minor axis of an ellipse that
458      * represents the touch area at the point of contact.
459      * The units are display pixels.
460      * - For a touch pad, reports the length of the minor axis of an ellipse that
461      * represents the touch area at the point of contact.
462      * The units are device-dependent.
463      *
464      * When the touch is circular, the major and minor axis lengths will be equal to one another.
465      */
466     AMOTION_EVENT_AXIS_TOUCH_MINOR = 5,
467     /**
468      * Axis constant: ToolMajor axis of a motion event.
469      *
470      * - For a touch screen, reports the length of the major axis of an ellipse that
471      * represents the size of the approaching finger or tool used to make contact.
472      * - For a touch pad, reports the length of the major axis of an ellipse that
473      * represents the size of the approaching finger or tool used to make contact.
474      * The units are device-dependent.
475      *
476      * When the touch is circular, the major and minor axis lengths will be equal to one another.
477      *
478      * The tool size may be larger than the touch size since the tool may not be fully
479      * in contact with the touch sensor.
480      */
481     AMOTION_EVENT_AXIS_TOOL_MAJOR = 6,
482     /**
483      * Axis constant: ToolMinor axis of a motion event.
484      *
485      * - For a touch screen, reports the length of the minor axis of an ellipse that
486      * represents the size of the approaching finger or tool used to make contact.
487      * - For a touch pad, reports the length of the minor axis of an ellipse that
488      * represents the size of the approaching finger or tool used to make contact.
489      * The units are device-dependent.
490      *
491      * When the touch is circular, the major and minor axis lengths will be equal to one another.
492      *
493      * The tool size may be larger than the touch size since the tool may not be fully
494      * in contact with the touch sensor.
495      */
496     AMOTION_EVENT_AXIS_TOOL_MINOR = 7,
497     /**
498      * Axis constant: Orientation axis of a motion event.
499      *
500      * - For a touch screen or touch pad, reports the orientation of the finger
501      * or tool in radians relative to the vertical plane of the device.
502      * An angle of 0 radians indicates that the major axis of contact is oriented
503      * upwards, is perfectly circular or is of unknown orientation.  A positive angle
504      * indicates that the major axis of contact is oriented to the right.  A negative angle
505      * indicates that the major axis of contact is oriented to the left.
506      * The full range is from -PI/2 radians (finger pointing fully left) to PI/2 radians
507      * (finger pointing fully right).
508      * - For a stylus, the orientation indicates the direction in which the stylus
509      * is pointing in relation to the vertical axis of the current orientation of the screen.
510      * The range is from -PI radians to PI radians, where 0 is pointing up,
511      * -PI/2 radians is pointing left, -PI or PI radians is pointing down, and PI/2 radians
512      * is pointing right.  See also {@link AMOTION_EVENT_AXIS_TILT}.
513      */
514     AMOTION_EVENT_AXIS_ORIENTATION = 8,
515     /**
516      * Axis constant: Vertical Scroll axis of a motion event.
517      *
518      * - For a mouse, reports the relative movement of the vertical scroll wheel.
519      * The value is normalized to a range from -1.0 (down) to 1.0 (up).
520      *
521      * This axis should be used to scroll views vertically.
522      */
523     AMOTION_EVENT_AXIS_VSCROLL = 9,
524     /**
525      * Axis constant: Horizontal Scroll axis of a motion event.
526      *
527      * - For a mouse, reports the relative movement of the horizontal scroll wheel.
528      * The value is normalized to a range from -1.0 (left) to 1.0 (right).
529      *
530      * This axis should be used to scroll views horizontally.
531      */
532     AMOTION_EVENT_AXIS_HSCROLL = 10,
533     /**
534      * Axis constant: Z axis of a motion event.
535      *
536      * - For a joystick, reports the absolute Z position of the joystick.
537      * The value is normalized to a range from -1.0 (high) to 1.0 (low).
538      * <em>On game pads with two analog joysticks, this axis is often reinterpreted
539      * to report the absolute X position of the second joystick instead.</em>
540      */
541     AMOTION_EVENT_AXIS_Z = 11,
542     /**
543      * Axis constant: X Rotation axis of a motion event.
544      *
545      * - For a joystick, reports the absolute rotation angle about the X axis.
546      * The value is normalized to a range from -1.0 (counter-clockwise) to 1.0 (clockwise).
547      */
548     AMOTION_EVENT_AXIS_RX = 12,
549     /**
550      * Axis constant: Y Rotation axis of a motion event.
551      *
552      * - For a joystick, reports the absolute rotation angle about the Y axis.
553      * The value is normalized to a range from -1.0 (counter-clockwise) to 1.0 (clockwise).
554      */
555     AMOTION_EVENT_AXIS_RY = 13,
556     /**
557      * Axis constant: Z Rotation axis of a motion event.
558      *
559      * - For a joystick, reports the absolute rotation angle about the Z axis.
560      * The value is normalized to a range from -1.0 (counter-clockwise) to 1.0 (clockwise).
561      * On game pads with two analog joysticks, this axis is often reinterpreted
562      * to report the absolute Y position of the second joystick instead.
563      */
564     AMOTION_EVENT_AXIS_RZ = 14,
565     /**
566      * Axis constant: Hat X axis of a motion event.
567      *
568      * - For a joystick, reports the absolute X position of the directional hat control.
569      * The value is normalized to a range from -1.0 (left) to 1.0 (right).
570      */
571     AMOTION_EVENT_AXIS_HAT_X = 15,
572     /**
573      * Axis constant: Hat Y axis of a motion event.
574      *
575      * - For a joystick, reports the absolute Y position of the directional hat control.
576      * The value is normalized to a range from -1.0 (up) to 1.0 (down).
577      */
578     AMOTION_EVENT_AXIS_HAT_Y = 16,
579     /**
580      * Axis constant: Left Trigger axis of a motion event.
581      *
582      * - For a joystick, reports the absolute position of the left trigger control.
583      * The value is normalized to a range from 0.0 (released) to 1.0 (fully pressed).
584      */
585     AMOTION_EVENT_AXIS_LTRIGGER = 17,
586     /**
587      * Axis constant: Right Trigger axis of a motion event.
588      *
589      * - For a joystick, reports the absolute position of the right trigger control.
590      * The value is normalized to a range from 0.0 (released) to 1.0 (fully pressed).
591      */
592     AMOTION_EVENT_AXIS_RTRIGGER = 18,
593     /**
594      * Axis constant: Throttle axis of a motion event.
595      *
596      * - For a joystick, reports the absolute position of the throttle control.
597      * The value is normalized to a range from 0.0 (fully open) to 1.0 (fully closed).
598      */
599     AMOTION_EVENT_AXIS_THROTTLE = 19,
600     /**
601      * Axis constant: Rudder axis of a motion event.
602      *
603      * - For a joystick, reports the absolute position of the rudder control.
604      * The value is normalized to a range from -1.0 (turn left) to 1.0 (turn right).
605      */
606     AMOTION_EVENT_AXIS_RUDDER = 20,
607     /**
608      * Axis constant: Wheel axis of a motion event.
609      *
610      * - For a joystick, reports the absolute position of the steering wheel control.
611      * The value is normalized to a range from -1.0 (turn left) to 1.0 (turn right).
612      */
613     AMOTION_EVENT_AXIS_WHEEL = 21,
614     /**
615      * Axis constant: Gas axis of a motion event.
616      *
617      * - For a joystick, reports the absolute position of the gas (accelerator) control.
618      * The value is normalized to a range from 0.0 (no acceleration)
619      * to 1.0 (maximum acceleration).
620      */
621     AMOTION_EVENT_AXIS_GAS = 22,
622     /**
623      * Axis constant: Brake axis of a motion event.
624      *
625      * - For a joystick, reports the absolute position of the brake control.
626      * The value is normalized to a range from 0.0 (no braking) to 1.0 (maximum braking).
627      */
628     AMOTION_EVENT_AXIS_BRAKE = 23,
629     /**
630      * Axis constant: Distance axis of a motion event.
631      *
632      * - For a stylus, reports the distance of the stylus from the screen.
633      * A value of 0.0 indicates direct contact and larger values indicate increasing
634      * distance from the surface.
635      */
636     AMOTION_EVENT_AXIS_DISTANCE = 24,
637     /**
638      * Axis constant: Tilt axis of a motion event.
639      *
640      * - For a stylus, reports the tilt angle of the stylus in radians where
641      * 0 radians indicates that the stylus is being held perpendicular to the
642      * surface, and PI/2 radians indicates that the stylus is being held flat
643      * against the surface.
644      */
645     AMOTION_EVENT_AXIS_TILT = 25,
646     /**
647      * Axis constant: Generic 1 axis of a motion event.
648      * The interpretation of a generic axis is device-specific.
649      */
650     AMOTION_EVENT_AXIS_GENERIC_1 = 32,
651     /**
652      * Axis constant: Generic 2 axis of a motion event.
653      * The interpretation of a generic axis is device-specific.
654      */
655     AMOTION_EVENT_AXIS_GENERIC_2 = 33,
656     /**
657      * Axis constant: Generic 3 axis of a motion event.
658      * The interpretation of a generic axis is device-specific.
659      */
660     AMOTION_EVENT_AXIS_GENERIC_3 = 34,
661     /**
662      * Axis constant: Generic 4 axis of a motion event.
663      * The interpretation of a generic axis is device-specific.
664      */
665     AMOTION_EVENT_AXIS_GENERIC_4 = 35,
666     /**
667      * Axis constant: Generic 5 axis of a motion event.
668      * The interpretation of a generic axis is device-specific.
669      */
670     AMOTION_EVENT_AXIS_GENERIC_5 = 36,
671     /**
672      * Axis constant: Generic 6 axis of a motion event.
673      * The interpretation of a generic axis is device-specific.
674      */
675     AMOTION_EVENT_AXIS_GENERIC_6 = 37,
676     /**
677      * Axis constant: Generic 7 axis of a motion event.
678      * The interpretation of a generic axis is device-specific.
679      */
680     AMOTION_EVENT_AXIS_GENERIC_7 = 38,
681     /**
682      * Axis constant: Generic 8 axis of a motion event.
683      * The interpretation of a generic axis is device-specific.
684      */
685     AMOTION_EVENT_AXIS_GENERIC_8 = 39,
686     /**
687      * Axis constant: Generic 9 axis of a motion event.
688      * The interpretation of a generic axis is device-specific.
689      */
690     AMOTION_EVENT_AXIS_GENERIC_9 = 40,
691     /**
692      * Axis constant: Generic 10 axis of a motion event.
693      * The interpretation of a generic axis is device-specific.
694      */
695     AMOTION_EVENT_AXIS_GENERIC_10 = 41,
696     /**
697      * Axis constant: Generic 11 axis of a motion event.
698      * The interpretation of a generic axis is device-specific.
699      */
700     AMOTION_EVENT_AXIS_GENERIC_11 = 42,
701     /**
702      * Axis constant: Generic 12 axis of a motion event.
703      * The interpretation of a generic axis is device-specific.
704      */
705     AMOTION_EVENT_AXIS_GENERIC_12 = 43,
706     /**
707      * Axis constant: Generic 13 axis of a motion event.
708      * The interpretation of a generic axis is device-specific.
709      */
710     AMOTION_EVENT_AXIS_GENERIC_13 = 44,
711     /**
712      * Axis constant: Generic 14 axis of a motion event.
713      * The interpretation of a generic axis is device-specific.
714      */
715     AMOTION_EVENT_AXIS_GENERIC_14 = 45,
716     /**
717      * Axis constant: Generic 15 axis of a motion event.
718      * The interpretation of a generic axis is device-specific.
719      */
720     AMOTION_EVENT_AXIS_GENERIC_15 = 46,
721     /**
722      * Axis constant: Generic 16 axis of a motion event.
723      * The interpretation of a generic axis is device-specific.
724      */
725     AMOTION_EVENT_AXIS_GENERIC_16 = 47,
726 
727     // NOTE: If you add a new axis here you must also add it to several other files.
728     //       Refer to frameworks/base/core/java/android/view/MotionEvent.java for the full list.
729 };
730 
731 /**
732  * Constants that identify buttons that are associated with motion events.
733  * Refer to the documentation on the MotionEvent class for descriptions of each button.
734  */
735 enum {
736     /** primary */
737     AMOTION_EVENT_BUTTON_PRIMARY = 1 << 0,
738     /** secondary */
739     AMOTION_EVENT_BUTTON_SECONDARY = 1 << 1,
740     /** tertiary */
741     AMOTION_EVENT_BUTTON_TERTIARY = 1 << 2,
742     /** back */
743     AMOTION_EVENT_BUTTON_BACK = 1 << 3,
744     /** forward */
745     AMOTION_EVENT_BUTTON_FORWARD = 1 << 4,
746     AMOTION_EVENT_BUTTON_STYLUS_PRIMARY = 1 << 5,
747     AMOTION_EVENT_BUTTON_STYLUS_SECONDARY = 1 << 6,
748 };
749 
750 /**
751  * Constants that identify tool types.
752  * Refer to the documentation on the MotionEvent class for descriptions of each tool type.
753  */
754 enum {
755     /** unknown */
756     AMOTION_EVENT_TOOL_TYPE_UNKNOWN = 0,
757     /** finger */
758     AMOTION_EVENT_TOOL_TYPE_FINGER = 1,
759     /** stylus */
760     AMOTION_EVENT_TOOL_TYPE_STYLUS = 2,
761     /** mouse */
762     AMOTION_EVENT_TOOL_TYPE_MOUSE = 3,
763     /** eraser */
764     AMOTION_EVENT_TOOL_TYPE_ERASER = 4,
765 };
766 
767 /**
768  * Input source masks.
769  *
770  * Refer to the documentation on android.view.InputDevice for more details about input sources
771  * and their correct interpretation.
772  */
773 enum {
774     /** mask */
775     AINPUT_SOURCE_CLASS_MASK = 0x000000ff,
776 
777     /** none */
778     AINPUT_SOURCE_CLASS_NONE = 0x00000000,
779     /** button */
780     AINPUT_SOURCE_CLASS_BUTTON = 0x00000001,
781     /** pointer */
782     AINPUT_SOURCE_CLASS_POINTER = 0x00000002,
783     /** navigation */
784     AINPUT_SOURCE_CLASS_NAVIGATION = 0x00000004,
785     /** position */
786     AINPUT_SOURCE_CLASS_POSITION = 0x00000008,
787     /** joystick */
788     AINPUT_SOURCE_CLASS_JOYSTICK = 0x00000010,
789 };
790 
791 /**
792  * Input sources.
793  */
794 enum {
795     /** unknown */
796     AINPUT_SOURCE_UNKNOWN = 0x00000000,
797 
798     /** keyboard */
799     AINPUT_SOURCE_KEYBOARD = 0x00000100 | AINPUT_SOURCE_CLASS_BUTTON,
800     /** dpad */
801     AINPUT_SOURCE_DPAD = 0x00000200 | AINPUT_SOURCE_CLASS_BUTTON,
802     /** gamepad */
803     AINPUT_SOURCE_GAMEPAD = 0x00000400 | AINPUT_SOURCE_CLASS_BUTTON,
804     /** touchscreen */
805     AINPUT_SOURCE_TOUCHSCREEN = 0x00001000 | AINPUT_SOURCE_CLASS_POINTER,
806     /** mouse */
807     AINPUT_SOURCE_MOUSE = 0x00002000 | AINPUT_SOURCE_CLASS_POINTER,
808     /** stylus */
809     AINPUT_SOURCE_STYLUS = 0x00004000 | AINPUT_SOURCE_CLASS_POINTER,
810     /** bluetooth stylus */
811     AINPUT_SOURCE_BLUETOOTH_STYLUS = 0x00008000 | AINPUT_SOURCE_STYLUS,
812     /** trackball */
813     AINPUT_SOURCE_TRACKBALL = 0x00010000 | AINPUT_SOURCE_CLASS_NAVIGATION,
814     /** touchpad */
815     AINPUT_SOURCE_TOUCHPAD = 0x00100000 | AINPUT_SOURCE_CLASS_POSITION,
816     /** navigation */
817     AINPUT_SOURCE_TOUCH_NAVIGATION = 0x00200000 | AINPUT_SOURCE_CLASS_NONE,
818     /** joystick */
819     AINPUT_SOURCE_JOYSTICK = 0x01000000 | AINPUT_SOURCE_CLASS_JOYSTICK,
820 
821     /** any */
822     AINPUT_SOURCE_ANY = 0xffffff00,
823 };
824 
825 /**
826  * Keyboard types.
827  *
828  * Refer to the documentation on android.view.InputDevice for more details.
829  */
830 enum {
831     /** none */
832     AINPUT_KEYBOARD_TYPE_NONE = 0,
833     /** non alphabetic */
834     AINPUT_KEYBOARD_TYPE_NON_ALPHABETIC = 1,
835     /** alphabetic */
836     AINPUT_KEYBOARD_TYPE_ALPHABETIC = 2,
837 };
838 
839 /**
840  * Constants used to retrieve information about the range of motion for a particular
841  * coordinate of a motion event.
842  *
843  * Refer to the documentation on android.view.InputDevice for more details about input sources
844  * and their correct interpretation.
845  *
846  * @deprecated These constants are deprecated. Use {@link AMOTION_EVENT_AXIS AMOTION_EVENT_AXIS_*} constants instead.
847  */
848 enum {
849     /** x */
850     AINPUT_MOTION_RANGE_X = AMOTION_EVENT_AXIS_X,
851     /** y */
852     AINPUT_MOTION_RANGE_Y = AMOTION_EVENT_AXIS_Y,
853     /** pressure */
854     AINPUT_MOTION_RANGE_PRESSURE = AMOTION_EVENT_AXIS_PRESSURE,
855     /** size */
856     AINPUT_MOTION_RANGE_SIZE = AMOTION_EVENT_AXIS_SIZE,
857     /** touch major */
858     AINPUT_MOTION_RANGE_TOUCH_MAJOR = AMOTION_EVENT_AXIS_TOUCH_MAJOR,
859     /** touch minor */
860     AINPUT_MOTION_RANGE_TOUCH_MINOR = AMOTION_EVENT_AXIS_TOUCH_MINOR,
861     /** tool major */
862     AINPUT_MOTION_RANGE_TOOL_MAJOR = AMOTION_EVENT_AXIS_TOOL_MAJOR,
863     /** tool minor */
864     AINPUT_MOTION_RANGE_TOOL_MINOR = AMOTION_EVENT_AXIS_TOOL_MINOR,
865     /** orientation */
866     AINPUT_MOTION_RANGE_ORIENTATION = AMOTION_EVENT_AXIS_ORIENTATION,
867 };
868 
869 
870 /**
871  * Input event accessors.
872  *
873  * Note that most functions can only be used on input events that are of a given type.
874  * Calling these functions on input events of other types will yield undefined behavior.
875  */
876 
877 /*** Accessors for all input events. ***/
878 
879 /** Get the input event type. */
880 int32_t AInputEvent_getType(const AInputEvent* event);
881 
882 /** Get the id for the device that an input event came from.
883  *
884  * Input events can be generated by multiple different input devices.
885  * Use the input device id to obtain information about the input
886  * device that was responsible for generating a particular event.
887  *
888  * An input device id of 0 indicates that the event didn't come from a physical device;
889  * other numbers are arbitrary and you shouldn't depend on the values.
890  * Use the provided input device query API to obtain information about input devices.
891  */
892 int32_t AInputEvent_getDeviceId(const AInputEvent* event);
893 
894 /** Get the input event source. */
895 int32_t AInputEvent_getSource(const AInputEvent* event);
896 
897 /*** Accessors for key events only. ***/
898 
899 /** Get the key event action. */
900 int32_t AKeyEvent_getAction(const AInputEvent* key_event);
901 
902 /** Get the key event flags. */
903 int32_t AKeyEvent_getFlags(const AInputEvent* key_event);
904 
905 /**
906  * Get the key code of the key event.
907  * This is the physical key that was pressed, not the Unicode character.
908  */
909 int32_t AKeyEvent_getKeyCode(const AInputEvent* key_event);
910 
911 /**
912  * Get the hardware key id of this key event.
913  * These values are not reliable and vary from device to device.
914  */
915 int32_t AKeyEvent_getScanCode(const AInputEvent* key_event);
916 
917 /** Get the meta key state. */
918 int32_t AKeyEvent_getMetaState(const AInputEvent* key_event);
919 
920 /**
921  * Get the repeat count of the event.
922  * For both key up an key down events, this is the number of times the key has
923  * repeated with the first down starting at 0 and counting up from there.  For
924  * multiple key events, this is the number of down/up pairs that have occurred.
925  */
926 int32_t AKeyEvent_getRepeatCount(const AInputEvent* key_event);
927 
928 /**
929  * Get the time of the most recent key down event, in the
930  * java.lang.System.nanoTime() time base.  If this is a down event,
931  * this will be the same as eventTime.
932  * Note that when chording keys, this value is the down time of the most recently
933  * pressed key, which may not be the same physical key of this event.
934  */
935 int64_t AKeyEvent_getDownTime(const AInputEvent* key_event);
936 
937 /**
938  * Get the time this event occurred, in the
939  * java.lang.System.nanoTime() time base.
940  */
941 int64_t AKeyEvent_getEventTime(const AInputEvent* key_event);
942 
943 /*** Accessors for motion events only. ***/
944 
945 /** Get the combined motion event action code and pointer index. */
946 int32_t AMotionEvent_getAction(const AInputEvent* motion_event);
947 
948 /** Get the motion event flags. */
949 int32_t AMotionEvent_getFlags(const AInputEvent* motion_event);
950 
951 /**
952  * Get the state of any meta / modifier keys that were in effect when the
953  * event was generated.
954  */
955 int32_t AMotionEvent_getMetaState(const AInputEvent* motion_event);
956 
957 /** Get the button state of all buttons that are pressed. */
958 int32_t AMotionEvent_getButtonState(const AInputEvent* motion_event);
959 
960 /**
961  * Get a bitfield indicating which edges, if any, were touched by this motion event.
962  * For touch events, clients can use this to determine if the user's finger was
963  * touching the edge of the display.
964  */
965 int32_t AMotionEvent_getEdgeFlags(const AInputEvent* motion_event);
966 
967 /**
968  * Get the time when the user originally pressed down to start a stream of
969  * position events, in the java.lang.System.nanoTime() time base.
970  */
971 int64_t AMotionEvent_getDownTime(const AInputEvent* motion_event);
972 
973 /**
974  * Get the time when this specific event was generated,
975  * in the java.lang.System.nanoTime() time base.
976  */
977 int64_t AMotionEvent_getEventTime(const AInputEvent* motion_event);
978 
979 /**
980  * Get the X coordinate offset.
981  * For touch events on the screen, this is the delta that was added to the raw
982  * screen coordinates to adjust for the absolute position of the containing windows
983  * and views.
984  */
985 float AMotionEvent_getXOffset(const AInputEvent* motion_event);
986 
987 /**
988  * Get the Y coordinate offset.
989  * For touch events on the screen, this is the delta that was added to the raw
990  * screen coordinates to adjust for the absolute position of the containing windows
991  * and views.
992  */
993 float AMotionEvent_getYOffset(const AInputEvent* motion_event);
994 
995 /**
996  * Get the precision of the X coordinates being reported.
997  * You can multiply this number with an X coordinate sample to find the
998  * actual hardware value of the X coordinate.
999  */
1000 float AMotionEvent_getXPrecision(const AInputEvent* motion_event);
1001 
1002 /**
1003  * Get the precision of the Y coordinates being reported.
1004  * You can multiply this number with a Y coordinate sample to find the
1005  * actual hardware value of the Y coordinate.
1006  */
1007 float AMotionEvent_getYPrecision(const AInputEvent* motion_event);
1008 
1009 /**
1010  * Get the number of pointers of data contained in this event.
1011  * Always >= 1.
1012  */
1013 size_t AMotionEvent_getPointerCount(const AInputEvent* motion_event);
1014 
1015 /**
1016  * Get the pointer identifier associated with a particular pointer
1017  * data index in this event.  The identifier tells you the actual pointer
1018  * number associated with the data, accounting for individual pointers
1019  * going up and down since the start of the current gesture.
1020  */
1021 int32_t AMotionEvent_getPointerId(const AInputEvent* motion_event, size_t pointer_index);
1022 
1023 /**
1024  * Get the tool type of a pointer for the given pointer index.
1025  * The tool type indicates the type of tool used to make contact such as a
1026  * finger or stylus, if known.
1027  */
1028 int32_t AMotionEvent_getToolType(const AInputEvent* motion_event, size_t pointer_index);
1029 
1030 /**
1031  * Get the original raw X coordinate of this event.
1032  * For touch events on the screen, this is the original location of the event
1033  * on the screen, before it had been adjusted for the containing window
1034  * and views.
1035  */
1036 float AMotionEvent_getRawX(const AInputEvent* motion_event, size_t pointer_index);
1037 
1038 /**
1039  * Get the original raw X coordinate of this event.
1040  * For touch events on the screen, this is the original location of the event
1041  * on the screen, before it had been adjusted for the containing window
1042  * and views.
1043  */
1044 float AMotionEvent_getRawY(const AInputEvent* motion_event, size_t pointer_index);
1045 
1046 /**
1047  * Get the current X coordinate of this event for the given pointer index.
1048  * Whole numbers are pixels; the value may have a fraction for input devices
1049  * that are sub-pixel precise.
1050  */
1051 float AMotionEvent_getX(const AInputEvent* motion_event, size_t pointer_index);
1052 
1053 /**
1054  * Get the current Y coordinate of this event for the given pointer index.
1055  * Whole numbers are pixels; the value may have a fraction for input devices
1056  * that are sub-pixel precise.
1057  */
1058 float AMotionEvent_getY(const AInputEvent* motion_event, size_t pointer_index);
1059 
1060 /**
1061  * Get the current pressure of this event for the given pointer index.
1062  * The pressure generally ranges from 0 (no pressure at all) to 1 (normal pressure),
1063  * although values higher than 1 may be generated depending on the calibration of
1064  * the input device.
1065  */
1066 float AMotionEvent_getPressure(const AInputEvent* motion_event, size_t pointer_index);
1067 
1068 /**
1069  * Get the current scaled value of the approximate size for the given pointer index.
1070  * This represents some approximation of the area of the screen being
1071  * pressed; the actual value in pixels corresponding to the
1072  * touch is normalized with the device specific range of values
1073  * and scaled to a value between 0 and 1.  The value of size can be used to
1074  * determine fat touch events.
1075  */
1076 float AMotionEvent_getSize(const AInputEvent* motion_event, size_t pointer_index);
1077 
1078 /**
1079  * Get the current length of the major axis of an ellipse that describes the touch area
1080  * at the point of contact for the given pointer index.
1081  */
1082 float AMotionEvent_getTouchMajor(const AInputEvent* motion_event, size_t pointer_index);
1083 
1084 /**
1085  * Get the current length of the minor axis of an ellipse that describes the touch area
1086  * at the point of contact for the given pointer index.
1087  */
1088 float AMotionEvent_getTouchMinor(const AInputEvent* motion_event, size_t pointer_index);
1089 
1090 /**
1091  * Get the current length of the major axis of an ellipse that describes the size
1092  * of the approaching tool for the given pointer index.
1093  * The tool area represents the estimated size of the finger or pen that is
1094  * touching the device independent of its actual touch area at the point of contact.
1095  */
1096 float AMotionEvent_getToolMajor(const AInputEvent* motion_event, size_t pointer_index);
1097 
1098 /**
1099  * Get the current length of the minor axis of an ellipse that describes the size
1100  * of the approaching tool for the given pointer index.
1101  * The tool area represents the estimated size of the finger or pen that is
1102  * touching the device independent of its actual touch area at the point of contact.
1103  */
1104 float AMotionEvent_getToolMinor(const AInputEvent* motion_event, size_t pointer_index);
1105 
1106 /**
1107  * Get the current orientation of the touch area and tool area in radians clockwise from
1108  * vertical for the given pointer index.
1109  * An angle of 0 degrees indicates that the major axis of contact is oriented
1110  * upwards, is perfectly circular or is of unknown orientation.  A positive angle
1111  * indicates that the major axis of contact is oriented to the right.  A negative angle
1112  * indicates that the major axis of contact is oriented to the left.
1113  * The full range is from -PI/2 radians (finger pointing fully left) to PI/2 radians
1114  * (finger pointing fully right).
1115  */
1116 float AMotionEvent_getOrientation(const AInputEvent* motion_event, size_t pointer_index);
1117 
1118 /** Get the value of the request axis for the given pointer index. */
1119 float AMotionEvent_getAxisValue(const AInputEvent* motion_event,
1120         int32_t axis, size_t pointer_index);
1121 
1122 /**
1123  * Get the number of historical points in this event.  These are movements that
1124  * have occurred between this event and the previous event.  This only applies
1125  * to AMOTION_EVENT_ACTION_MOVE events -- all other actions will have a size of 0.
1126  * Historical samples are indexed from oldest to newest.
1127  */
1128 size_t AMotionEvent_getHistorySize(const AInputEvent* motion_event);
1129 
1130 /**
1131  * Get the time that a historical movement occurred between this event and
1132  * the previous event, in the java.lang.System.nanoTime() time base.
1133  */
1134 int64_t AMotionEvent_getHistoricalEventTime(const AInputEvent* motion_event,
1135         size_t history_index);
1136 
1137 /**
1138  * Get the historical raw X coordinate of this event for the given pointer index that
1139  * occurred between this event and the previous motion event.
1140  * For touch events on the screen, this is the original location of the event
1141  * on the screen, before it had been adjusted for the containing window
1142  * and views.
1143  * Whole numbers are pixels; the value may have a fraction for input devices
1144  * that are sub-pixel precise.
1145  */
1146 float AMotionEvent_getHistoricalRawX(const AInputEvent* motion_event, size_t pointer_index,
1147         size_t history_index);
1148 
1149 /**
1150  * Get the historical raw Y coordinate of this event for the given pointer index that
1151  * occurred between this event and the previous motion event.
1152  * For touch events on the screen, this is the original location of the event
1153  * on the screen, before it had been adjusted for the containing window
1154  * and views.
1155  * Whole numbers are pixels; the value may have a fraction for input devices
1156  * that are sub-pixel precise.
1157  */
1158 float AMotionEvent_getHistoricalRawY(const AInputEvent* motion_event, size_t pointer_index,
1159         size_t history_index);
1160 
1161 /**
1162  * Get the historical X coordinate of this event for the given pointer index that
1163  * occurred between this event and the previous motion event.
1164  * Whole numbers are pixels; the value may have a fraction for input devices
1165  * that are sub-pixel precise.
1166  */
1167 float AMotionEvent_getHistoricalX(const AInputEvent* motion_event, size_t pointer_index,
1168         size_t history_index);
1169 
1170 /**
1171  * Get the historical Y coordinate of this event for the given pointer index that
1172  * occurred between this event and the previous motion event.
1173  * Whole numbers are pixels; the value may have a fraction for input devices
1174  * that are sub-pixel precise.
1175  */
1176 float AMotionEvent_getHistoricalY(const AInputEvent* motion_event, size_t pointer_index,
1177         size_t history_index);
1178 
1179 /**
1180  * Get the historical pressure of this event for the given pointer index that
1181  * occurred between this event and the previous motion event.
1182  * The pressure generally ranges from 0 (no pressure at all) to 1 (normal pressure),
1183  * although values higher than 1 may be generated depending on the calibration of
1184  * the input device.
1185  */
1186 float AMotionEvent_getHistoricalPressure(const AInputEvent* motion_event, size_t pointer_index,
1187         size_t history_index);
1188 
1189 /**
1190  * Get the current scaled value of the approximate size for the given pointer index that
1191  * occurred between this event and the previous motion event.
1192  * This represents some approximation of the area of the screen being
1193  * pressed; the actual value in pixels corresponding to the
1194  * touch is normalized with the device specific range of values
1195  * and scaled to a value between 0 and 1.  The value of size can be used to
1196  * determine fat touch events.
1197  */
1198 float AMotionEvent_getHistoricalSize(const AInputEvent* motion_event, size_t pointer_index,
1199         size_t history_index);
1200 
1201 /**
1202  * Get the historical length of the major axis of an ellipse that describes the touch area
1203  * at the point of contact for the given pointer index that
1204  * occurred between this event and the previous motion event.
1205  */
1206 float AMotionEvent_getHistoricalTouchMajor(const AInputEvent* motion_event, size_t pointer_index,
1207         size_t history_index);
1208 
1209 /**
1210  * Get the historical length of the minor axis of an ellipse that describes the touch area
1211  * at the point of contact for the given pointer index that
1212  * occurred between this event and the previous motion event.
1213  */
1214 float AMotionEvent_getHistoricalTouchMinor(const AInputEvent* motion_event, size_t pointer_index,
1215         size_t history_index);
1216 
1217 /**
1218  * Get the historical length of the major axis of an ellipse that describes the size
1219  * of the approaching tool for the given pointer index that
1220  * occurred between this event and the previous motion event.
1221  * The tool area represents the estimated size of the finger or pen that is
1222  * touching the device independent of its actual touch area at the point of contact.
1223  */
1224 float AMotionEvent_getHistoricalToolMajor(const AInputEvent* motion_event, size_t pointer_index,
1225         size_t history_index);
1226 
1227 /**
1228  * Get the historical length of the minor axis of an ellipse that describes the size
1229  * of the approaching tool for the given pointer index that
1230  * occurred between this event and the previous motion event.
1231  * The tool area represents the estimated size of the finger or pen that is
1232  * touching the device independent of its actual touch area at the point of contact.
1233  */
1234 float AMotionEvent_getHistoricalToolMinor(const AInputEvent* motion_event, size_t pointer_index,
1235         size_t history_index);
1236 
1237 /**
1238  * Get the historical orientation of the touch area and tool area in radians clockwise from
1239  * vertical for the given pointer index that
1240  * occurred between this event and the previous motion event.
1241  * An angle of 0 degrees indicates that the major axis of contact is oriented
1242  * upwards, is perfectly circular or is of unknown orientation.  A positive angle
1243  * indicates that the major axis of contact is oriented to the right.  A negative angle
1244  * indicates that the major axis of contact is oriented to the left.
1245  * The full range is from -PI/2 radians (finger pointing fully left) to PI/2 radians
1246  * (finger pointing fully right).
1247  */
1248 float AMotionEvent_getHistoricalOrientation(const AInputEvent* motion_event, size_t pointer_index,
1249         size_t history_index);
1250 
1251 /**
1252  * Get the historical value of the request axis for the given pointer index
1253  * that occurred between this event and the previous motion event.
1254  */
1255 float AMotionEvent_getHistoricalAxisValue(const AInputEvent* motion_event,
1256         int32_t axis, size_t pointer_index, size_t history_index);
1257 
1258 
1259 struct AInputQueue;
1260 /**
1261  * Input queue
1262  *
1263  * An input queue is the facility through which you retrieve input
1264  * events.
1265  */
1266 typedef struct AInputQueue AInputQueue;
1267 
1268 /**
1269  * Add this input queue to a looper for processing.  See
1270  * ALooper_addFd() for information on the ident, callback, and data params.
1271  */
1272 void AInputQueue_attachLooper(AInputQueue* queue, ALooper* looper,
1273         int ident, ALooper_callbackFunc callback, void* data);
1274 
1275 /**
1276  * Remove the input queue from the looper it is currently attached to.
1277  */
1278 void AInputQueue_detachLooper(AInputQueue* queue);
1279 
1280 /**
1281  * Returns true if there are one or more events available in the
1282  * input queue.  Returns 1 if the queue has events; 0 if
1283  * it does not have events; and a negative value if there is an error.
1284  */
1285 int32_t AInputQueue_hasEvents(AInputQueue* queue);
1286 
1287 /**
1288  * Returns the next available event from the queue.  Returns a negative
1289  * value if no events are available or an error has occurred.
1290  */
1291 int32_t AInputQueue_getEvent(AInputQueue* queue, AInputEvent** outEvent);
1292 
1293 /**
1294  * Sends the key for standard pre-dispatching -- that is, possibly deliver
1295  * it to the current IME to be consumed before the app.  Returns 0 if it
1296  * was not pre-dispatched, meaning you can process it right now.  If non-zero
1297  * is returned, you must abandon the current event processing and allow the
1298  * event to appear again in the event queue (if it does not get consumed during
1299  * pre-dispatching).
1300  */
1301 int32_t AInputQueue_preDispatchEvent(AInputQueue* queue, AInputEvent* event);
1302 
1303 /**
1304  * Report that dispatching has finished with the given event.
1305  * This must be called after receiving an event with AInputQueue_get_event().
1306  */
1307 void AInputQueue_finishEvent(AInputQueue* queue, AInputEvent* event, int handled);
1308 
1309 #ifdef __cplusplus
1310 }
1311 #endif
1312 
1313 #endif // _ANDROID_INPUT_H
1314 
1315 /** @} */
1316