1 // Copyright (c) 2011 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef UI_VIEWS_CONTROLS_NATIVE_CONTROL_H_ 6 #define UI_VIEWS_CONTROLS_NATIVE_CONTROL_H_ 7 8 #include <windows.h> 9 10 #include "ui/events/keycodes/keyboard_codes.h" 11 #include "ui/views/view.h" 12 13 namespace views { 14 15 class NativeViewHost; 16 class NativeControlContainer; 17 18 //////////////////////////////////////////////////////////////////////////////// 19 // 20 // NativeControl is an abstract view that is used to implement views wrapping 21 // native controls. Subclasses can simply implement CreateNativeControl() to 22 // wrap a new kind of control 23 // 24 //////////////////////////////////////////////////////////////////////////////// 25 class VIEWS_EXPORT NativeControl : public View { 26 public: 27 enum Alignment { 28 LEADING = 0, 29 CENTER, 30 TRAILING }; 31 32 NativeControl(); 33 virtual ~NativeControl(); 34 35 virtual void ViewHierarchyChanged( 36 const ViewHierarchyChangedDetails& details) OVERRIDE; 37 virtual void Layout(); 38 39 // Overridden to properly set the native control state. 40 virtual void SetVisible(bool f); 41 virtual void OnEnabledChanged(); 42 43 // Overridden to do nothing. 44 virtual void OnPaint(gfx::Canvas* canvas); 45 46 protected: 47 friend class NativeControlContainer; 48 49 // Overridden by sub-classes to create the windows control which is wrapped 50 virtual HWND CreateNativeControl(HWND parent_container) = 0; 51 52 // Invoked when the native control sends a WM_NOTIFY message to its parent 53 virtual LRESULT OnNotify(int w_param, LPNMHDR l_param) = 0; 54 55 // Invoked when the native control sends a WM_COMMAND message to its parent OnCommand(UINT code,int id,HWND source)56 virtual LRESULT OnCommand(UINT code, int id, HWND source) { return 0; } 57 58 // Invoked when the appropriate gesture for a context menu is issued. 59 virtual void OnContextMenu(const POINT& location); 60 61 // Overridden so to set the native focus to the native control. 62 virtual void OnFocus(); 63 64 // Invoked when the native control sends a WM_DESTORY message to its parent. OnDestroy()65 virtual void OnDestroy() { } 66 67 // Return the native control 68 virtual HWND GetNativeControlHWND(); 69 70 // Invoked by the native windows control when it has been destroyed. This is 71 // invoked AFTER WM_DESTORY has been sent. Any window commands send to the 72 // HWND will most likely fail. 73 void NativeControlDestroyed(); 74 75 // Overridden so that the control properly reflects parent's visibility. 76 virtual void VisibilityChanged(View* starting_from, bool is_visible); 77 78 // Controls that have fixed sizes should call these methods to specify the 79 // actual size and how they should be aligned within their parent. 80 void SetFixedWidth(int width, Alignment alignment); 81 void SetFixedHeight(int height, Alignment alignment); 82 83 // Invoked when a key is pressed on the control. 84 // Should return true if the key message was processed, false otherwise. OnKeyDown(ui::KeyboardCode virtual_key_code)85 virtual bool OnKeyDown(ui::KeyboardCode virtual_key_code) { return false; } 86 87 // Returns additional extended style flags. When subclasses call 88 // CreateWindowEx in order to create the underlying control, they must OR the 89 // ExStyle parameter with the value returned by this function. 90 // 91 // We currently use this method in order to add flags such as WS_EX_LAYOUTRTL 92 // to the HWND for views with right-to-left UI layout. 93 DWORD GetAdditionalExStyle() const; 94 95 // TODO(xji): we use the following temporary function as we transition the 96 // various native controls to use the right set of RTL flags. This function 97 // will go away (and be replaced by GetAdditionalExStyle()) once all the 98 // controls are properly transitioned. 99 DWORD GetAdditionalRTLStyle() const; 100 101 // This variable is protected to provide subclassers direct access. However 102 // subclassers should always check for NULL since this variable is only 103 // initialized in ValidateNativeControl(). 104 NativeViewHost* hwnd_view_; 105 106 // Fixed size information. -1 for a size means no fixed size. 107 int fixed_width_; 108 Alignment horizontal_alignment_; 109 int fixed_height_; 110 Alignment vertical_alignment_; 111 112 private: 113 114 void ValidateNativeControl(); 115 116 static LRESULT CALLBACK NativeControlWndProc(HWND window, UINT message, 117 WPARAM w_param, LPARAM l_param); 118 119 NativeControlContainer* container_; 120 121 DISALLOW_COPY_AND_ASSIGN(NativeControl); 122 }; 123 124 } // namespace views 125 126 #endif // UI_VIEWS_CONTROLS_NATIVE_CONTROL_H_ 127