1 // Copyright (c) 2012 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_BASE_IME_INPUT_METHOD_BASE_H_ 6 #define UI_BASE_IME_INPUT_METHOD_BASE_H_ 7 8 #include "base/basictypes.h" 9 #include "base/compiler_specific.h" 10 #include "base/memory/weak_ptr.h" 11 #include "base/observer_list.h" 12 #include "ui/base/ime/input_method.h" 13 #include "ui/base/ui_export.h" 14 15 namespace gfx { 16 class Rect; 17 } // namespace gfx 18 19 namespace ui { 20 21 class InputMethodObserver; 22 class KeyEvent; 23 class TextInputClient; 24 25 // A helper class providing functionalities shared among ui::InputMethod 26 // implementations. 27 class UI_EXPORT InputMethodBase NON_EXPORTED_BASE(public InputMethod)28 : NON_EXPORTED_BASE(public InputMethod), 29 public base::SupportsWeakPtr<InputMethodBase> { 30 public: 31 InputMethodBase(); 32 virtual ~InputMethodBase(); 33 34 // Overriden from InputMethod. 35 virtual void SetDelegate(internal::InputMethodDelegate* delegate) OVERRIDE; 36 virtual void Init(bool focused) OVERRIDE; 37 // If a derived class overrides OnFocus()/OnBlur(), it should call parent's 38 // implementation first, to make sure |system_toplevel_window_focused_| flag 39 // can be updated correctly. 40 virtual void OnFocus() OVERRIDE; 41 virtual void OnBlur() OVERRIDE; 42 virtual void SetFocusedTextInputClient(TextInputClient* client) OVERRIDE; 43 virtual void DetachTextInputClient(TextInputClient* client) OVERRIDE; 44 virtual TextInputClient* GetTextInputClient() const OVERRIDE; 45 46 // If a derived class overrides this method, it should call parent's 47 // implementation. 48 virtual void OnTextInputTypeChanged(const TextInputClient* client) OVERRIDE; 49 50 virtual TextInputType GetTextInputType() const OVERRIDE; 51 virtual TextInputMode GetTextInputMode() const OVERRIDE; 52 virtual bool CanComposeInline() const OVERRIDE; 53 54 virtual void AddObserver(InputMethodObserver* observer) OVERRIDE; 55 virtual void RemoveObserver(InputMethodObserver* observer) OVERRIDE; 56 57 protected: 58 virtual void OnWillChangeFocusedClient(TextInputClient* focused_before, 59 TextInputClient* focused) {} 60 virtual void OnDidChangeFocusedClient(TextInputClient* focused_before, 61 TextInputClient* focused) {} 62 63 // Returns true if |client| is currently focused. 64 bool IsTextInputClientFocused(const TextInputClient* client); 65 66 // Checks if the focused text input client's text input type is 67 // TEXT_INPUT_TYPE_NONE. Also returns true if there is no focused text 68 // input client. 69 bool IsTextInputTypeNone() const; 70 71 // Convenience method to call the focused text input client's 72 // OnInputMethodChanged() method. It'll only take effect if the current text 73 // input type is not TEXT_INPUT_TYPE_NONE. 74 void OnInputMethodChanged() const; 75 76 // Convenience method to call delegate_->DispatchKeyEventPostIME(). 77 // Returns true if the event was processed 78 bool DispatchKeyEventPostIME(const ui::KeyEvent& event) const; 79 80 // Convenience method to notify all observers of TextInputClient changes. 81 void NotifyTextInputStateChanged(const TextInputClient* client); 82 83 // Interface for for signalling candidate window events. 84 // See also *Callback functions below. To avoid reentrancy issue that 85 // TextInputClient manipulates IME state during even handling, these methods 86 // defer sending actual signals to renderer. 87 void OnCandidateWindowShown(); 88 void OnCandidateWindowUpdated(); 89 void OnCandidateWindowHidden(); 90 91 bool system_toplevel_window_focused() const { 92 return system_toplevel_window_focused_; 93 } 94 95 private: 96 void SetFocusedTextInputClientInternal(TextInputClient* client); 97 98 // Deferred callbacks for signalling TextInputClient about candidate window 99 // appearance changes. 100 void CandidateWindowShownCallback(); 101 void CandidateWindowUpdatedCallback(); 102 void CandidateWindowHiddenCallback(); 103 104 internal::InputMethodDelegate* delegate_; 105 TextInputClient* text_input_client_; 106 107 ObserverList<InputMethodObserver> observer_list_; 108 109 bool system_toplevel_window_focused_; 110 111 DISALLOW_COPY_AND_ASSIGN(InputMethodBase); 112 }; 113 114 } // namespace ui 115 116 #endif // UI_BASE_IME_INPUT_METHOD_BASE_H_ 117