New InputMethod api for Views.

views/ime/text_input_client.h

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef VIEWS_IME_TEXT_INPUT_CLIENT_H_
+#define VIEWS_IME_TEXT_INPUT_CLIENT_H_
+#pragma once
+
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/callback.h"
+#include "base/string16.h"
+#include "ui/base/ime/composition_text.h"
+#include "ui/base/ime/text_input_type.h"
+#include "ui/base/range/range.h"
+
+namespace gfx {
+class Rect;
+}
+
+namespace views {
+
+// An interface implemented by a View that needs text input support.
+class TextInputClient {
+ public:
+  virtual ~TextInputClient() {}
+
+  // Input method result -------------------------------------------------------
+
+  // Sets composition text and attributes. If there is composition text already,
+  // it’ll be replaced by the new one. Otherwise, current selection will be
+  // replaced. If there is no selection, the composition text will be inserted
+  // at the insertion point.
+  virtual void SetCompositionText(const ui::CompositionText& composition) = 0;

[Peng, 2011/03/29 19:12:19]

For Touch UI, sometimes, we want to show composition in candidates panel or
virtual keyboard instead of in input control views. Could you add this support
for Chrome IME API?

[James Su, 2011/03/29 19:39:15]

It should be handled inside the actual InputMethod implementation, which should
send the composition text to appropriate component. And it's not necessary for a
text input client to know it.

[Peng, 2011/03/29 19:50:47]

I think that code should be part of browser UI, instead of views or a special
InputMethod implementations.

On 2011/03/29 19:39:15, James Su wrote:

[James Su, 2011/03/29 22:32:38]

If it's part of TouchUI's browser code, then it makes sense to add specific
API's to InputMethodIBus class for calling from TouchUI's specific browser code.
It's not a generic requirement that should be added to this interface.

+
+  // Converts current composition text into final content.
+  virtual void ConfirmCompositionText() = 0;
+
+  // Removes current composition text.
+  virtual void ClearCompositionText() = 0;
+
+  // Inserts a given text at the insertion point. Current composition text or
+  // selection will be removed. This method should never be called when the
+  // current text input type is TEXT_INPUT_TYPE_NONE.
+  virtual void InsertText(const string16& text) = 0;
+
+  // Inserts a single char at the insertion point. Unlike above InsertText()
+  // method, this method has an extra |flags| parameter indicating the modifier
+  // key states when the character is generated. This method should only be
+  // called when a key press is not handled by the input method but still
+  // generates a character (eg. by the keyboard driver). In another word, the
+  // preceding key press event should not be a VKEY_PROCESSKEY.
+  // This method will be called whenever a char is generated by the keyboard,
+  // even if the current text input type is TEXT_INPUT_TYPE_NONE.
+  virtual void InsertChar(char16 ch, int flags) = 0;
+
+  // Input context information -------------------------------------------------
+
+  // Returns current text input type. It could be changed and even becomes
+  // TEXT_INPUT_TYPE_NONE at runtime.
+  virtual ui::TextInputType GetTextInputType() = 0;
+
+  // Returns current caret (insertion point) bounds relative to the View’s
+  // coordinates. If there is selection, then the selection bounds will be
+  // returned.
+  virtual gfx::Rect GetCaretBounds() = 0;
+
+  // Returns true if there is composition text.
+  virtual bool HasCompositionText() = 0;
+
+  // Document content operations ----------------------------------------------
+
+  // Retrieves the UTF-16 based character range containing all text in the View.
+  // Returns false if the information cannot be retrieved right now.
+  virtual bool GetTextRange(ui::Range* range) = 0;
+
+  // Retrieves the UTF-16 based character range of current composition text.
+  // Returns false if the information cannot be retrieved right now.
+  virtual bool GetCompositionTextRange(ui::Range* range) = 0;
+
+  // Retrieves the UTF-16 based character range of current selection.
+  // Returns false if the information cannot be retrieved right now.
+  virtual bool GetSelectionRange(ui::Range* range) = 0;
+
+  // Selects the given UTF-16 based character range. Current composition text
+  // will be confirmed before selecting the range.
+  // Returns false if the operation is not supported.
+  virtual bool SetSelectionRange(const ui::Range& range) = 0;
+
+  // Deletes contents in the given UTF-16 based character range. Current
+  // composition text will be confirmed before deleting the range.
+  // The input caret will be moved to the place where the range gets deleted.
+  // Returns false if the oepration is not supported.
+  virtual bool DeleteRange(const ui::Range& range) = 0;
+
+  // Retrieves the text content in a given UTF-16 based character range.
+  // The result will be send back to the input method by calling the given
+  // callback, which may happen asynchronously.
+  // Returns false if the operation is not supported.
+  virtual bool GetTextFromRange(
+      const ui::Range& range,
+      const base::Callback<void(const string16&)>& callback) = 0;
+
+  // Miscellaneous ------------------------------------------------------------
+
+  // Called whenever current keyboard layout or input method is changed,
+  // especially the change of input locale and text direction.
+  virtual void OnInputMethodChanged() = 0;
+
+  // Called whenever the user requests to change the text direction and layout
+  // alignment of the current text box. It’s for supporting ctrl-shift on
+  // Windows.
+  // Returns false if the operation is not supported.
+  virtual bool ChangeTextDirectionAndLayoutAlignment(
+      base::i18n::TextDirection direction) = 0;
+};

[Peng, 2011/03/29 19:50:47]

It is better to have a function to get view pointer of the InputClient.

[James Su, 2011/03/29 22:32:38]

Done.

+
+}  // namespace views
+
+#endif  // VIEWS_IME_TEXT_INPUT_CLIENT_H_