1 /* 2 * Copyright (C) 2011 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 package android.view; 18 19 import android.annotation.NonNull; 20 import android.annotation.Nullable; 21 import android.annotation.XmlRes; 22 import android.compat.annotation.UnsupportedAppUsage; 23 import android.content.Context; 24 import android.content.res.Resources; 25 import android.content.res.TypedArray; 26 import android.content.res.XmlResourceParser; 27 import android.graphics.Bitmap; 28 import android.graphics.Canvas; 29 import android.graphics.Paint; 30 import android.graphics.Rect; 31 import android.graphics.RectF; 32 import android.graphics.drawable.AnimationDrawable; 33 import android.graphics.drawable.BitmapDrawable; 34 import android.graphics.drawable.Drawable; 35 import android.hardware.display.DisplayManager; 36 import android.os.Build; 37 import android.os.Parcel; 38 import android.os.Parcelable; 39 import android.util.Log; 40 import android.util.SparseArray; 41 42 import com.android.internal.util.XmlUtils; 43 44 /** 45 * Represents an icon that can be used as a mouse pointer. 46 * <p> 47 * Pointer icons can be provided either by the system using system types, 48 * or by applications using bitmaps or application resources. 49 * </p> 50 */ 51 public final class PointerIcon implements Parcelable { 52 private static final String TAG = "PointerIcon"; 53 54 /** {@hide} Type constant: Custom icon with a user-supplied bitmap. */ 55 public static final int TYPE_CUSTOM = -1; 56 57 /** Type constant: Null icon. It has no bitmap. */ 58 public static final int TYPE_NULL = 0; 59 60 /** Type constant: no icons are specified. If all views uses this, then falls back 61 * to the default type, but this is helpful to distinguish a view explicitly want 62 * to have the default icon. 63 * @hide 64 */ 65 public static final int TYPE_NOT_SPECIFIED = 1; 66 67 /** Type constant: Arrow icon. (Default mouse pointer) */ 68 public static final int TYPE_ARROW = 1000; 69 70 /** {@hide} Type constant: Spot hover icon for touchpads. */ 71 public static final int TYPE_SPOT_HOVER = 2000; 72 73 /** {@hide} Type constant: Spot touch icon for touchpads. */ 74 public static final int TYPE_SPOT_TOUCH = 2001; 75 76 /** {@hide} Type constant: Spot anchor icon for touchpads. */ 77 public static final int TYPE_SPOT_ANCHOR = 2002; 78 79 // Type constants for additional predefined icons for mice. 80 /** Type constant: context-menu. */ 81 public static final int TYPE_CONTEXT_MENU = 1001; 82 83 /** Type constant: hand. */ 84 public static final int TYPE_HAND = 1002; 85 86 /** Type constant: help. */ 87 public static final int TYPE_HELP = 1003; 88 89 /** Type constant: wait. */ 90 public static final int TYPE_WAIT = 1004; 91 92 /** Type constant: cell. */ 93 public static final int TYPE_CELL = 1006; 94 95 /** Type constant: crosshair. */ 96 public static final int TYPE_CROSSHAIR = 1007; 97 98 /** Type constant: text. */ 99 public static final int TYPE_TEXT = 1008; 100 101 /** Type constant: vertical-text. */ 102 public static final int TYPE_VERTICAL_TEXT = 1009; 103 104 /** Type constant: alias (indicating an alias of/shortcut to something is 105 * to be created. */ 106 public static final int TYPE_ALIAS = 1010; 107 108 /** Type constant: copy. */ 109 public static final int TYPE_COPY = 1011; 110 111 /** Type constant: no-drop. */ 112 public static final int TYPE_NO_DROP = 1012; 113 114 /** Type constant: all-scroll. */ 115 public static final int TYPE_ALL_SCROLL = 1013; 116 117 /** Type constant: horizontal double arrow mainly for resizing. */ 118 public static final int TYPE_HORIZONTAL_DOUBLE_ARROW = 1014; 119 120 /** Type constant: vertical double arrow mainly for resizing. */ 121 public static final int TYPE_VERTICAL_DOUBLE_ARROW = 1015; 122 123 /** Type constant: diagonal double arrow -- top-right to bottom-left. */ 124 public static final int TYPE_TOP_RIGHT_DIAGONAL_DOUBLE_ARROW = 1016; 125 126 /** Type constant: diagonal double arrow -- top-left to bottom-right. */ 127 public static final int TYPE_TOP_LEFT_DIAGONAL_DOUBLE_ARROW = 1017; 128 129 /** Type constant: zoom-in. */ 130 public static final int TYPE_ZOOM_IN = 1018; 131 132 /** Type constant: zoom-out. */ 133 public static final int TYPE_ZOOM_OUT = 1019; 134 135 /** Type constant: grab. */ 136 public static final int TYPE_GRAB = 1020; 137 138 /** Type constant: grabbing. */ 139 public static final int TYPE_GRABBING = 1021; 140 141 // OEM private types should be defined starting at this range to avoid 142 // conflicts with any system types that may be defined in the future. 143 private static final int TYPE_OEM_FIRST = 10000; 144 145 /** The default pointer icon. */ 146 public static final int TYPE_DEFAULT = TYPE_ARROW; 147 148 private static final PointerIcon gNullIcon = new PointerIcon(TYPE_NULL); 149 private static final SparseArray<SparseArray<PointerIcon>> gSystemIconsByDisplay = 150 new SparseArray<SparseArray<PointerIcon>>(); 151 private static boolean sUseLargeIcons = false; 152 153 @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) 154 private final int mType; 155 private int mSystemIconResourceId; 156 @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) 157 private Bitmap mBitmap; 158 @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) 159 private float mHotSpotX; 160 @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) 161 private float mHotSpotY; 162 // The bitmaps for the additional frame of animated pointer icon. Note that the first frame 163 // will be stored in mBitmap. 164 @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) 165 private Bitmap mBitmapFrames[]; 166 @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) 167 private int mDurationPerFrame; 168 169 /** 170 * Listener for displays lifecycle. 171 * @hide 172 */ 173 private static DisplayManager.DisplayListener sDisplayListener; 174 PointerIcon(int type)175 private PointerIcon(int type) { 176 mType = type; 177 } 178 179 /** 180 * Gets a special pointer icon that has no bitmap. 181 * 182 * @return The null pointer icon. 183 * 184 * @see #TYPE_NULL 185 * @hide 186 */ getNullIcon()187 public static PointerIcon getNullIcon() { 188 return gNullIcon; 189 } 190 191 /** 192 * Gets the default pointer icon. 193 * 194 * @param context The context. 195 * @return The default pointer icon. 196 * 197 * @throws IllegalArgumentException if context is null. 198 * @hide 199 */ getDefaultIcon(@onNull Context context)200 public static PointerIcon getDefaultIcon(@NonNull Context context) { 201 return getSystemIcon(context, TYPE_DEFAULT); 202 } 203 204 /** 205 * Gets a system pointer icon for the given type. 206 * If typeis not recognized, returns the default pointer icon. 207 * 208 * @param context The context. 209 * @param type The pointer icon type. 210 * @return The pointer icon. 211 * 212 * @throws IllegalArgumentException if context is null. 213 */ getSystemIcon(@onNull Context context, int type)214 public static PointerIcon getSystemIcon(@NonNull Context context, int type) { 215 if (context == null) { 216 throw new IllegalArgumentException("context must not be null"); 217 } 218 219 if (type == TYPE_NULL) { 220 return gNullIcon; 221 } 222 223 if (sDisplayListener == null) { 224 registerDisplayListener(context); 225 } 226 227 final int displayId = context.getDisplayId(); 228 SparseArray<PointerIcon> systemIcons = gSystemIconsByDisplay.get(displayId); 229 if (systemIcons == null) { 230 systemIcons = new SparseArray<>(); 231 gSystemIconsByDisplay.put(displayId, systemIcons); 232 } 233 234 PointerIcon icon = systemIcons.get(type); 235 // Reload if not in the same display. 236 if (icon != null) { 237 return icon; 238 } 239 240 int typeIndex = getSystemIconTypeIndex(type); 241 if (typeIndex == 0) { 242 typeIndex = getSystemIconTypeIndex(TYPE_DEFAULT); 243 } 244 245 int defStyle = sUseLargeIcons ? 246 com.android.internal.R.style.LargePointer : com.android.internal.R.style.Pointer; 247 TypedArray a = context.obtainStyledAttributes(null, 248 com.android.internal.R.styleable.Pointer, 249 0, defStyle); 250 int resourceId = a.getResourceId(typeIndex, -1); 251 a.recycle(); 252 253 if (resourceId == -1) { 254 Log.w(TAG, "Missing theme resources for pointer icon type " + type); 255 return type == TYPE_DEFAULT ? gNullIcon : getSystemIcon(context, TYPE_DEFAULT); 256 } 257 258 icon = new PointerIcon(type); 259 if ((resourceId & 0xff000000) == 0x01000000) { 260 icon.mSystemIconResourceId = resourceId; 261 } else { 262 icon.loadResource(context, context.getResources(), resourceId); 263 } 264 systemIcons.append(type, icon); 265 return icon; 266 } 267 268 /** 269 * Updates wheter accessibility large icons are used or not. 270 * @hide 271 */ setUseLargeIcons(boolean use)272 public static void setUseLargeIcons(boolean use) { 273 sUseLargeIcons = use; 274 gSystemIconsByDisplay.clear(); 275 } 276 277 /** 278 * Creates a custom pointer icon from the given bitmap and hotspot information. 279 * 280 * @param bitmap The bitmap for the icon. 281 * @param hotSpotX The X offset of the pointer icon hotspot in the bitmap. 282 * Must be within the [0, bitmap.getWidth()) range. 283 * @param hotSpotY The Y offset of the pointer icon hotspot in the bitmap. 284 * Must be within the [0, bitmap.getHeight()) range. 285 * @return A pointer icon for this bitmap. 286 * 287 * @throws IllegalArgumentException if bitmap is null, or if the x/y hotspot 288 * parameters are invalid. 289 */ create(@onNull Bitmap bitmap, float hotSpotX, float hotSpotY)290 public static PointerIcon create(@NonNull Bitmap bitmap, float hotSpotX, float hotSpotY) { 291 if (bitmap == null) { 292 throw new IllegalArgumentException("bitmap must not be null"); 293 } 294 validateHotSpot(bitmap, hotSpotX, hotSpotY); 295 296 PointerIcon icon = new PointerIcon(TYPE_CUSTOM); 297 icon.mBitmap = bitmap; 298 icon.mHotSpotX = hotSpotX; 299 icon.mHotSpotY = hotSpotY; 300 return icon; 301 } 302 303 /** 304 * Loads a custom pointer icon from an XML resource. 305 * <p> 306 * The XML resource should have the following form: 307 * <code> 308 * <?xml version="1.0" encoding="utf-8"?> 309 * <pointer-icon xmlns:android="http://schemas.android.com/apk/res/android" 310 * android:bitmap="@drawable/my_pointer_bitmap" 311 * android:hotSpotX="24" 312 * android:hotSpotY="24" /> 313 * </code> 314 * </p> 315 * 316 * @param resources The resources object. 317 * @param resourceId The resource id. 318 * @return The pointer icon. 319 * 320 * @throws IllegalArgumentException if resources is null. 321 * @throws Resources.NotFoundException if the resource was not found or the drawable 322 * linked in the resource was not found. 323 */ load(@onNull Resources resources, @XmlRes int resourceId)324 public static PointerIcon load(@NonNull Resources resources, @XmlRes int resourceId) { 325 if (resources == null) { 326 throw new IllegalArgumentException("resources must not be null"); 327 } 328 329 PointerIcon icon = new PointerIcon(TYPE_CUSTOM); 330 icon.loadResource(null, resources, resourceId); 331 return icon; 332 } 333 334 /** 335 * Loads the bitmap and hotspot information for a pointer icon, if it is not already loaded. 336 * Returns a pointer icon (not necessarily the same instance) with the information filled in. 337 * 338 * @param context The context. 339 * @return The loaded pointer icon. 340 * 341 * @throws IllegalArgumentException if context is null. 342 * @hide 343 */ 344 @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) load(@onNull Context context)345 public PointerIcon load(@NonNull Context context) { 346 if (context == null) { 347 throw new IllegalArgumentException("context must not be null"); 348 } 349 350 if (mSystemIconResourceId == 0 || mBitmap != null) { 351 return this; 352 } 353 354 PointerIcon result = new PointerIcon(mType); 355 result.mSystemIconResourceId = mSystemIconResourceId; 356 result.loadResource(context, context.getResources(), mSystemIconResourceId); 357 return result; 358 } 359 360 /** @hide */ getType()361 public int getType() { 362 return mType; 363 } 364 365 public static final @android.annotation.NonNull Parcelable.Creator<PointerIcon> CREATOR 366 = new Parcelable.Creator<PointerIcon>() { 367 public PointerIcon createFromParcel(Parcel in) { 368 int type = in.readInt(); 369 if (type == TYPE_NULL) { 370 return getNullIcon(); 371 } 372 373 int systemIconResourceId = in.readInt(); 374 if (systemIconResourceId != 0) { 375 PointerIcon icon = new PointerIcon(type); 376 icon.mSystemIconResourceId = systemIconResourceId; 377 return icon; 378 } 379 380 Bitmap bitmap = Bitmap.CREATOR.createFromParcel(in); 381 float hotSpotX = in.readFloat(); 382 float hotSpotY = in.readFloat(); 383 return PointerIcon.create(bitmap, hotSpotX, hotSpotY); 384 } 385 386 public PointerIcon[] newArray(int size) { 387 return new PointerIcon[size]; 388 } 389 }; 390 describeContents()391 public int describeContents() { 392 return 0; 393 } 394 writeToParcel(Parcel out, int flags)395 public void writeToParcel(Parcel out, int flags) { 396 out.writeInt(mType); 397 398 if (mType != TYPE_NULL) { 399 out.writeInt(mSystemIconResourceId); 400 if (mSystemIconResourceId == 0) { 401 mBitmap.writeToParcel(out, flags); 402 out.writeFloat(mHotSpotX); 403 out.writeFloat(mHotSpotY); 404 } 405 } 406 } 407 408 @Override equals(@ullable Object other)409 public boolean equals(@Nullable Object other) { 410 if (this == other) { 411 return true; 412 } 413 414 if (other == null || !(other instanceof PointerIcon)) { 415 return false; 416 } 417 418 PointerIcon otherIcon = (PointerIcon) other; 419 if (mType != otherIcon.mType 420 || mSystemIconResourceId != otherIcon.mSystemIconResourceId) { 421 return false; 422 } 423 424 if (mSystemIconResourceId == 0 && (mBitmap != otherIcon.mBitmap 425 || mHotSpotX != otherIcon.mHotSpotX 426 || mHotSpotY != otherIcon.mHotSpotY)) { 427 return false; 428 } 429 430 return true; 431 } 432 433 /** 434 * Get the Bitmap from the Drawable. 435 * 436 * If the Bitmap needed to be scaled up to account for density, BitmapDrawable 437 * handles this at draw time. But this class doesn't actually draw the Bitmap; 438 * it is just a holder for native code to access its SkBitmap. So this needs to 439 * get a version that is scaled to account for density. 440 */ getBitmapFromDrawable(BitmapDrawable bitmapDrawable)441 private Bitmap getBitmapFromDrawable(BitmapDrawable bitmapDrawable) { 442 Bitmap bitmap = bitmapDrawable.getBitmap(); 443 final int scaledWidth = bitmapDrawable.getIntrinsicWidth(); 444 final int scaledHeight = bitmapDrawable.getIntrinsicHeight(); 445 if (scaledWidth == bitmap.getWidth() && scaledHeight == bitmap.getHeight()) { 446 return bitmap; 447 } 448 449 Rect src = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight()); 450 RectF dst = new RectF(0, 0, scaledWidth, scaledHeight); 451 452 Bitmap scaled = Bitmap.createBitmap(scaledWidth, scaledHeight, bitmap.getConfig()); 453 Canvas canvas = new Canvas(scaled); 454 Paint paint = new Paint(); 455 paint.setFilterBitmap(true); 456 canvas.drawBitmap(bitmap, src, dst, paint); 457 return scaled; 458 } 459 loadResource(Context context, Resources resources, @XmlRes int resourceId)460 private void loadResource(Context context, Resources resources, @XmlRes int resourceId) { 461 final XmlResourceParser parser = resources.getXml(resourceId); 462 final int bitmapRes; 463 final float hotSpotX; 464 final float hotSpotY; 465 try { 466 XmlUtils.beginDocument(parser, "pointer-icon"); 467 468 final TypedArray a = resources.obtainAttributes( 469 parser, com.android.internal.R.styleable.PointerIcon); 470 bitmapRes = a.getResourceId(com.android.internal.R.styleable.PointerIcon_bitmap, 0); 471 hotSpotX = a.getDimension(com.android.internal.R.styleable.PointerIcon_hotSpotX, 0); 472 hotSpotY = a.getDimension(com.android.internal.R.styleable.PointerIcon_hotSpotY, 0); 473 a.recycle(); 474 } catch (Exception ex) { 475 throw new IllegalArgumentException("Exception parsing pointer icon resource.", ex); 476 } finally { 477 parser.close(); 478 } 479 480 if (bitmapRes == 0) { 481 throw new IllegalArgumentException("<pointer-icon> is missing bitmap attribute."); 482 } 483 484 Drawable drawable; 485 if (context == null) { 486 drawable = resources.getDrawable(bitmapRes); 487 } else { 488 drawable = context.getDrawable(bitmapRes); 489 } 490 if (drawable instanceof AnimationDrawable) { 491 // Extract animation frame bitmaps. 492 final AnimationDrawable animationDrawable = (AnimationDrawable) drawable; 493 final int frames = animationDrawable.getNumberOfFrames(); 494 drawable = animationDrawable.getFrame(0); 495 if (frames == 1) { 496 Log.w(TAG, "Animation icon with single frame -- simply treating the first " 497 + "frame as a normal bitmap icon."); 498 } else { 499 // Assumes they have the exact duration. 500 mDurationPerFrame = animationDrawable.getDuration(0); 501 mBitmapFrames = new Bitmap[frames - 1]; 502 final int width = drawable.getIntrinsicWidth(); 503 final int height = drawable.getIntrinsicHeight(); 504 for (int i = 1; i < frames; ++i) { 505 Drawable drawableFrame = animationDrawable.getFrame(i); 506 if (!(drawableFrame instanceof BitmapDrawable)) { 507 throw new IllegalArgumentException("Frame of an animated pointer icon " 508 + "must refer to a bitmap drawable."); 509 } 510 if (drawableFrame.getIntrinsicWidth() != width || 511 drawableFrame.getIntrinsicHeight() != height) { 512 throw new IllegalArgumentException("The bitmap size of " + i + "-th frame " 513 + "is different. All frames should have the exact same size and " 514 + "share the same hotspot."); 515 } 516 BitmapDrawable bitmapDrawableFrame = (BitmapDrawable) drawableFrame; 517 mBitmapFrames[i - 1] = getBitmapFromDrawable(bitmapDrawableFrame); 518 } 519 } 520 } 521 if (!(drawable instanceof BitmapDrawable)) { 522 throw new IllegalArgumentException("<pointer-icon> bitmap attribute must " 523 + "refer to a bitmap drawable."); 524 } 525 526 BitmapDrawable bitmapDrawable = (BitmapDrawable) drawable; 527 final Bitmap bitmap = getBitmapFromDrawable(bitmapDrawable); 528 validateHotSpot(bitmap, hotSpotX, hotSpotY); 529 // Set the properties now that we have successfully loaded the icon. 530 mBitmap = bitmap; 531 mHotSpotX = hotSpotX; 532 mHotSpotY = hotSpotY; 533 } 534 validateHotSpot(Bitmap bitmap, float hotSpotX, float hotSpotY)535 private static void validateHotSpot(Bitmap bitmap, float hotSpotX, float hotSpotY) { 536 if (hotSpotX < 0 || hotSpotX >= bitmap.getWidth()) { 537 throw new IllegalArgumentException("x hotspot lies outside of the bitmap area"); 538 } 539 if (hotSpotY < 0 || hotSpotY >= bitmap.getHeight()) { 540 throw new IllegalArgumentException("y hotspot lies outside of the bitmap area"); 541 } 542 } 543 getSystemIconTypeIndex(int type)544 private static int getSystemIconTypeIndex(int type) { 545 switch (type) { 546 case TYPE_ARROW: 547 return com.android.internal.R.styleable.Pointer_pointerIconArrow; 548 case TYPE_SPOT_HOVER: 549 return com.android.internal.R.styleable.Pointer_pointerIconSpotHover; 550 case TYPE_SPOT_TOUCH: 551 return com.android.internal.R.styleable.Pointer_pointerIconSpotTouch; 552 case TYPE_SPOT_ANCHOR: 553 return com.android.internal.R.styleable.Pointer_pointerIconSpotAnchor; 554 case TYPE_HAND: 555 return com.android.internal.R.styleable.Pointer_pointerIconHand; 556 case TYPE_CONTEXT_MENU: 557 return com.android.internal.R.styleable.Pointer_pointerIconContextMenu; 558 case TYPE_HELP: 559 return com.android.internal.R.styleable.Pointer_pointerIconHelp; 560 case TYPE_WAIT: 561 return com.android.internal.R.styleable.Pointer_pointerIconWait; 562 case TYPE_CELL: 563 return com.android.internal.R.styleable.Pointer_pointerIconCell; 564 case TYPE_CROSSHAIR: 565 return com.android.internal.R.styleable.Pointer_pointerIconCrosshair; 566 case TYPE_TEXT: 567 return com.android.internal.R.styleable.Pointer_pointerIconText; 568 case TYPE_VERTICAL_TEXT: 569 return com.android.internal.R.styleable.Pointer_pointerIconVerticalText; 570 case TYPE_ALIAS: 571 return com.android.internal.R.styleable.Pointer_pointerIconAlias; 572 case TYPE_COPY: 573 return com.android.internal.R.styleable.Pointer_pointerIconCopy; 574 case TYPE_ALL_SCROLL: 575 return com.android.internal.R.styleable.Pointer_pointerIconAllScroll; 576 case TYPE_NO_DROP: 577 return com.android.internal.R.styleable.Pointer_pointerIconNodrop; 578 case TYPE_HORIZONTAL_DOUBLE_ARROW: 579 return com.android.internal.R.styleable.Pointer_pointerIconHorizontalDoubleArrow; 580 case TYPE_VERTICAL_DOUBLE_ARROW: 581 return com.android.internal.R.styleable.Pointer_pointerIconVerticalDoubleArrow; 582 case TYPE_TOP_RIGHT_DIAGONAL_DOUBLE_ARROW: 583 return com.android.internal.R.styleable. 584 Pointer_pointerIconTopRightDiagonalDoubleArrow; 585 case TYPE_TOP_LEFT_DIAGONAL_DOUBLE_ARROW: 586 return com.android.internal.R.styleable. 587 Pointer_pointerIconTopLeftDiagonalDoubleArrow; 588 case TYPE_ZOOM_IN: 589 return com.android.internal.R.styleable.Pointer_pointerIconZoomIn; 590 case TYPE_ZOOM_OUT: 591 return com.android.internal.R.styleable.Pointer_pointerIconZoomOut; 592 case TYPE_GRAB: 593 return com.android.internal.R.styleable.Pointer_pointerIconGrab; 594 case TYPE_GRABBING: 595 return com.android.internal.R.styleable.Pointer_pointerIconGrabbing; 596 default: 597 return 0; 598 } 599 } 600 601 /** 602 * Manage system icon cache handled by display lifecycle. 603 * @param context The context. 604 */ registerDisplayListener(@onNull Context context)605 private static void registerDisplayListener(@NonNull Context context) { 606 sDisplayListener = new DisplayManager.DisplayListener() { 607 @Override 608 public void onDisplayAdded(int displayId) { 609 } 610 611 @Override 612 public void onDisplayRemoved(int displayId) { 613 gSystemIconsByDisplay.remove(displayId); 614 } 615 616 @Override 617 public void onDisplayChanged(int displayId) { 618 gSystemIconsByDisplay.remove(displayId); 619 } 620 }; 621 622 DisplayManager displayManager = context.getSystemService(DisplayManager.class); 623 displayManager.registerDisplayListener(sDisplayListener, null /* handler */); 624 } 625 626 } 627