1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
|
// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
// This code is distributed under the GNU LGPL (for details please see \doc\license.txt)
using System;
using System.ComponentModel;
using System.Diagnostics;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Security;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using System.Windows.Interop;
using System.Windows.Media;
using System.Windows.Media.TextFormatting;
using ICSharpCode.AvalonEdit;
using ICSharpCode.AvalonEdit.Document;
using ICSharpCode.AvalonEdit.Rendering;
namespace ICSharpCode.AvalonEdit.Editing
{
class ImeSupport
{
readonly TextArea textArea;
IntPtr currentContext;
IntPtr previousContext;
IntPtr defaultImeWnd;
HwndSource hwndSource;
EventHandler requerySuggestedHandler; // we need to keep the event handler instance alive because CommandManager.RequerySuggested uses weak references
bool isReadOnly;
public ImeSupport(TextArea textArea)
{
if (textArea == null)
throw new ArgumentNullException("textArea");
this.textArea = textArea;
InputMethod.SetIsInputMethodSuspended(this.textArea, textArea.Options.EnableImeSupport);
// We listen to CommandManager.RequerySuggested for both caret offset changes and changes to the set of read-only sections.
// This is because there's no dedicated event for read-only section changes; but RequerySuggested needs to be raised anyways
// to invalidate the Paste command.
requerySuggestedHandler = OnRequerySuggested;
CommandManager.RequerySuggested += requerySuggestedHandler;
textArea.OptionChanged += TextAreaOptionChanged;
}
void OnRequerySuggested(object sender, EventArgs e)
{
UpdateImeEnabled();
}
void TextAreaOptionChanged(object sender, PropertyChangedEventArgs e)
{
if (e.PropertyName == "EnableImeSupport") {
InputMethod.SetIsInputMethodSuspended(this.textArea, textArea.Options.EnableImeSupport);
UpdateImeEnabled();
}
}
public void OnGotKeyboardFocus(KeyboardFocusChangedEventArgs e)
{
UpdateImeEnabled();
}
public void OnLostKeyboardFocus(KeyboardFocusChangedEventArgs e)
{
if (e.OldFocus == textArea && currentContext != IntPtr.Zero)
ImeNativeWrapper.NotifyIme(currentContext);
ClearContext();
}
void UpdateImeEnabled()
{
if (textArea.Options.EnableImeSupport && textArea.IsKeyboardFocused) {
bool newReadOnly = !textArea.ReadOnlySectionProvider.CanInsert(textArea.Caret.Offset);
if (hwndSource == null || isReadOnly != newReadOnly) {
ClearContext(); // clear existing context (on read-only change)
isReadOnly = newReadOnly;
CreateContext();
}
} else {
ClearContext();
}
}
void ClearContext()
{
if (hwndSource != null) {
ImeNativeWrapper.ImmAssociateContext(hwndSource.Handle, previousContext);
ImeNativeWrapper.ImmReleaseContext(defaultImeWnd, currentContext);
currentContext = IntPtr.Zero;
defaultImeWnd = IntPtr.Zero;
hwndSource.RemoveHook(WndProc);
hwndSource = null;
}
}
void CreateContext()
{
hwndSource = (HwndSource)PresentationSource.FromVisual(this.textArea);
if (hwndSource != null) {
if (isReadOnly) {
defaultImeWnd = IntPtr.Zero;
currentContext = IntPtr.Zero;
} else {
defaultImeWnd = ImeNativeWrapper.ImmGetDefaultIMEWnd(IntPtr.Zero);
currentContext = ImeNativeWrapper.ImmGetContext(defaultImeWnd);
}
previousContext = ImeNativeWrapper.ImmAssociateContext(hwndSource.Handle, currentContext);
hwndSource.AddHook(WndProc);
// UpdateCompositionWindow() will be called by the caret becoming visible
var threadMgr = ImeNativeWrapper.GetTextFrameworkThreadManager();
if (threadMgr != null) {
// Even though the docu says passing null is invalid, this seems to help
// activating the IME on the default input context that is shared with WPF
threadMgr.SetFocus(IntPtr.Zero);
}
}
}
IntPtr WndProc(IntPtr hWnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
switch (msg) {
case ImeNativeWrapper.WM_INPUTLANGCHANGE:
// Don't mark the message as handled; other windows
// might want to handle it as well.
// If we have a context, recreate it
if (hwndSource != null) {
ClearContext();
CreateContext();
}
break;
case ImeNativeWrapper.WM_IME_COMPOSITION:
UpdateCompositionWindow();
break;
}
return IntPtr.Zero;
}
public void UpdateCompositionWindow()
{
if (currentContext != IntPtr.Zero) {
ImeNativeWrapper.SetCompositionFont(hwndSource, currentContext, textArea);
ImeNativeWrapper.SetCompositionWindow(hwndSource, currentContext, textArea);
}
}
}
}
|
