ui/base/ime/input_method_auralinux.h

   1 // Copyright 2013 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_AURALINUX_H_
   6 #define UI_BASE_IME_INPUT_METHOD_AURALINUX_H_
   7
   8 #include "base/memory/scoped_ptr.h"
   9 #include "ui/base/ime/input_method_base.h"
  10 #include "ui/base/ime/linux/linux_input_method_context.h"
  11
  12 namespace ui {
  13
  14 // A ui::InputMethod implementation for Aura on Linux platforms. The
  15 // implementation details are separated to ui::LinuxInputMethodContext
  16 // interface.
  17 class UI_BASE_EXPORT InputMethodAuraLinux
  18     : public InputMethodBase,
  19       public LinuxInputMethodContextDelegate {
  20  public:
  21   explicit InputMethodAuraLinux(internal::InputMethodDelegate* delegate);
  22   virtual ~InputMethodAuraLinux();
  23
  24   // Overriden from InputMethod.
  25   virtual void Init(bool focused) OVERRIDE;
  26   virtual bool OnUntranslatedIMEMessage(const base::NativeEvent& event,
  27                                         NativeEventResult* result) OVERRIDE;
  28   virtual bool DispatchKeyEvent(const ui::KeyEvent& event) OVERRIDE;
  29   virtual void OnTextInputTypeChanged(const TextInputClient* client) OVERRIDE;
  30   virtual void OnCaretBoundsChanged(const TextInputClient* client) OVERRIDE;
  31   virtual void CancelComposition(const TextInputClient* client) OVERRIDE;
  32   virtual void OnInputLocaleChanged() OVERRIDE;
  33   virtual std::string GetInputLocale() OVERRIDE;
  34   virtual bool IsActive() OVERRIDE;
  35   virtual bool IsCandidatePopupOpen() const OVERRIDE;
  36
  37   // Overriden from ui::LinuxInputMethodContextDelegate
  38   virtual void OnCommit(const base::string16& text) OVERRIDE;
  39   virtual void OnPreeditChanged(const CompositionText& composition_text)
  40       OVERRIDE;
  41   virtual void OnPreeditEnd() OVERRIDE;
  42   virtual void OnPreeditStart() OVERRIDE;
  43
  44  protected:
  45   // Overridden from InputMethodBase.
  46   virtual void OnDidChangeFocusedClient(TextInputClient* focused_before,
  47                                         TextInputClient* focused) OVERRIDE;
  48
  49  private:
  50   // Allows to fire a VKEY_PROCESSKEY key event.
  51   void AllowToFireProcessKey(const ui::KeyEvent& event);
  52   // Fires a VKEY_PROCESSKEY key event if allowed.
  53   void MaybeFireProcessKey();
  54   // Stops firing VKEY_PROCESSKEY key events.
  55   void StopFiringProcessKey();
  56
  57   scoped_ptr<LinuxInputMethodContext> input_method_context_;
  58
  59   // IBus in async mode eagerly consumes all the key events first regardless of
  60   // whether the underlying IME consumes the key event or not, and makes
  61   // gtk_im_context_filter_keypress() always return true, and later pushes
  62   // the key event back to the GDK event queue when it turns out that the
  63   // underlying IME doesn't consume the key event.
  64   //
  65   // Thus we have to defer a decision whether or not to dispatch a
  66   // VKEY_PROCESSKEY key event.  Unlike other InputMethod's subclasses,
  67   // DispatchKeyEvent() in this class does not directly dispatch a
  68   // VKEY_PROCESSKEY event, OnCommit or OnPreedit{Start,Changed,End} dispatch
  69   // a VKEY_PROCESSKEY event instead.
  70   //
  71   // Because of this hack, there could be chances that we accidentally dispatch
  72   // VKEY_PROCESSKEY events and other key events in out of order.
  73   //
  74   // |allowed_to_fire_vkey_process_key_| is used not to dispatch a
  75   // VKEY_PROCESSKEY event twice for a single key event.
  76   bool allowed_to_fire_vkey_process_key_;
  77   int vkey_processkey_flags_;
  78
  79   DISALLOW_COPY_AND_ASSIGN(InputMethodAuraLinux);
  80 };
  81
  82 }  // namespace ui
  83
  84 #endif  // UI_BASE_IME_INPUT_METHOD_AURALINUX_H_