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//---------------------------------------------------------------------------
//
// <copyright file=InputLanguageManager.cs company=Microsoft>
// Copyright (C) Microsoft Corporation. All rights reserved.
// </copyright>
//
//
// Description: InputLanguageManager class and InputLanguage APIs.
//
// History:
// 07/30/2003 : yutakas - ported from dotnet tree.
//
//---------------------------------------------------------------------------
using System.Collections;
using System.Windows.Threading;
using System.Windows;
using System.Globalization;
using MS.Win32;
using System;
using System.Security;
using System.Runtime.InteropServices;
using System.ComponentModel;
using SR=MS.Internal.PresentationCore.SR;
using SRID=MS.Internal.PresentationCore.SRID;
namespace System.Windows.Input
{
/// <summary>
/// The InputLanguageManager class is responsible for mmanaging
/// the input language in Avalon.
/// </summary>
public sealed class InputLanguageManager : DispatcherObject
{
/// <summary>
/// This is the property of the preferred input language of the
/// element.
/// When the element get focus, this input language is selected
/// automatically.
/// </summary>
public static readonly DependencyProperty InputLanguageProperty =
DependencyProperty.RegisterAttached(
"InputLanguage",
typeof(CultureInfo),
typeof(InputLanguageManager),
new PropertyMetadata(CultureInfo.InvariantCulture)
);
/// <summary>
/// Setter for InputLanguage DependencyProperty
/// </summary>
public static void SetInputLanguage(DependencyObject target, CultureInfo inputLanguage)
{
if (target == null)
{
throw new ArgumentNullException("target");
}
target.SetValue(InputLanguageProperty, inputLanguage);
}
/// <summary>
/// Getter for InputLanguage DependencyProperty
/// </summary>
[AttachedPropertyBrowsableForType(typeof(DependencyObject))]
[TypeConverter(typeof(System.Windows.CultureInfoIetfLanguageTagConverter))]
public static CultureInfo GetInputLanguage(DependencyObject target)
{
if (target == null)
{
throw new ArgumentNullException("target");
}
return (CultureInfo)(target.GetValue(InputLanguageProperty));
}
/// <summary>
/// If this is true, the previous inputlanguage is restored
/// when the element with InputLanguage dynamicproperty lose the focus.
/// This property is ignored if InputLanguage dynamic property is
/// not available in the element.
/// </summary>
public static readonly DependencyProperty RestoreInputLanguageProperty =
DependencyProperty.RegisterAttached(
"RestoreInputLanguage",
typeof(bool),
typeof(InputLanguageManager),
new PropertyMetadata(false)
);
/// <summary>
/// Setter for RestoreInputLanguage DependencyProperty
/// </summary>
public static void SetRestoreInputLanguage(DependencyObject target, bool restore)
{
if (target == null)
{
throw new ArgumentNullException("target");
}
target.SetValue(RestoreInputLanguageProperty, restore);
}
/// <summary>
/// Getter for RestoreInputLanguage DependencyProperty
/// </summary>
[AttachedPropertyBrowsableForType(typeof(DependencyObject))]
public static bool GetRestoreInputLanguage(DependencyObject target)
{
if (target == null)
{
throw new ArgumentNullException("target");
}
return (bool)(target.GetValue(RestoreInputLanguageProperty));
}
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
private InputLanguageManager()
{
// register our default input language source.
RegisterInputLanguageSource(new InputLanguageSource(this));
}
//------------------------------------------------------
//
// Public Methods
//
//------------------------------------------------------
#region Public Methods
/// <summary>
/// Registers an input language soruces with the input
/// input language manager.
/// </summary>
/// <param name="inputLanguageSource">
/// The input language source to register.
/// </param>
public void RegisterInputLanguageSource(IInputLanguageSource inputLanguageSource)
{
if (inputLanguageSource == null)
{
throw new ArgumentNullException("inputLanguageSource");
}
_source = inputLanguageSource;
if (((_InputLanguageChanged != null) ||
(_InputLanguageChanging != null)) &&
IsMultipleKeyboardLayout)
_source.Initialize();
return;
}
/// <summary>
/// Report the input language is changed from the source.
/// </summary>
/// <param name="newLanguageId">
/// The new language id.
/// </param>
/// <param name="previousLanguageId">
/// The previous language id.
/// </param>
public void ReportInputLanguageChanged(
CultureInfo newLanguageId,
CultureInfo previousLanguageId)
{
if (newLanguageId == null)
{
throw new ArgumentNullException("newLanguageId");
}
if (previousLanguageId == null)
{
throw new ArgumentNullException("previousLanguageId");
}
//
// if this language change was not done by SetFocus() and
// InputLanguage Property of the element, we clear _previousLanguageId.
//
if (!previousLanguageId.Equals(_previousLanguageId))
{
_previousLanguageId = null;
}
if (_InputLanguageChanged != null)
{
InputLanguageChangedEventArgs args = new InputLanguageChangedEventArgs(newLanguageId, previousLanguageId);
// Stability Review: Task#32416
// - No state to be restored even exception happens while this callback.
_InputLanguageChanged(this, args);
}
}
/// <summary>
/// Report the input language is being changed from the source.
/// </summary>
/// <param name="newLanguageId">
/// The new language id.
/// </param>
/// <param name="previousLanguageId">
/// The previous language id.
/// </param>
public bool ReportInputLanguageChanging(
CultureInfo newLanguageId,
CultureInfo previousLanguageId)
{
if (newLanguageId == null)
{
throw new ArgumentNullException("newLanguageId");
}
if (previousLanguageId == null)
{
throw new ArgumentNullException("previousLanguageId");
}
bool accepted = true;
if (_InputLanguageChanging != null)
{
InputLanguageChangingEventArgs args = new InputLanguageChangingEventArgs(newLanguageId, previousLanguageId);
// Stability Review: Task#32416
// - No state to be restored even exception happens while this callback.
_InputLanguageChanging(this, args);
accepted = args.Rejected ? false : true;
}
return accepted;
}
#endregion Public Methods
//------------------------------------------------------
//
// Public Operators
//
//------------------------------------------------------
//------------------------------------------------------
//
// Public Properties
//
//------------------------------------------------------
/// <summary>
/// Return the input language manager associated
/// with the current context.
/// </summary>
public static InputLanguageManager Current
{
get
{
// InputLanguageManager for the current Dispatcher is stored in InputMethod of
// the current Dispatcher.
if(InputMethod.Current.InputLanguageManager == null)
{
InputMethod.Current.InputLanguageManager = new InputLanguageManager();
}
return InputMethod.Current.InputLanguageManager;
}
}
/// <summary>
/// This accesses the input language associated
/// with the current context.
/// </summary>
[TypeConverter(typeof(System.Windows.CultureInfoIetfLanguageTagConverter))]
public CultureInfo CurrentInputLanguage
{
get
{
// If the source is available, we should use it.
if (_source != null)
{
return _source.CurrentInputLanguage;
}
IntPtr hkl = SafeNativeMethods.GetKeyboardLayout(0);
if (hkl == IntPtr.Zero)
{
return CultureInfo.InvariantCulture;
}
// This needs to work before source is attached.
return new CultureInfo((short)NativeMethods.IntPtrToInt32(hkl));
}
set
{
if (value == null)
{
throw new ArgumentNullException("value");
}
SetSourceCurrentLanguageId(value);
}
}
/// <summary>
/// Return enumerator for available input languages.
/// </summary>
public IEnumerable AvailableInputLanguages
{
get
{
if (_source == null)
{
return null;
}
return (IEnumerable)_source.InputLanguageList;
}
}
//------------------------------------------------------
//
// Public Events
//
//------------------------------------------------------
/// <summary>
/// This is an event when the input language is changed.
/// </summary>
public event InputLanguageEventHandler InputLanguageChanged
{
add
{
if (value == null)
{
throw new ArgumentNullException("value");
}
if ((_InputLanguageChanged == null) &&
(_InputLanguageChanging == null) &&
IsMultipleKeyboardLayout &&
(_source != null))
_source.Initialize();
_InputLanguageChanged += value;
}
remove
{
if (value == null)
{
throw new ArgumentNullException("value");
}
_InputLanguageChanged -= value;
if ((_InputLanguageChanged == null) &&
(_InputLanguageChanging == null) &&
IsMultipleKeyboardLayout &&
(_source != null))
_source.Uninitialize();
}
}
/// <summary>
/// This is an event when the input language is being changed.
/// </summary>
public event InputLanguageEventHandler InputLanguageChanging
{
add
{
if (value == null)
{
throw new ArgumentNullException("value");
}
if ((_InputLanguageChanged == null) &&
(_InputLanguageChanging == null) &&
IsMultipleKeyboardLayout &&
(_source != null))
_source.Initialize();
_InputLanguageChanging += value;
}
remove
{
if (value == null)
{
throw new ArgumentNullException("value");
}
_InputLanguageChanging -= value;
if ((_InputLanguageChanged == null) &&
(_InputLanguageChanging == null) &&
IsMultipleKeyboardLayout &&
(_source != null))
_source.Uninitialize();
}
}
//------------------------------------------------------
//
// Protected Methods
//
//------------------------------------------------------
//------------------------------------------------------
//
// Internal Methods
//
//------------------------------------------------------
#region Internal Methods
/// <summary>
/// When keyboard device gets focus, this is called.
/// We will check the preferred input language of focus element.
/// </summary>
internal void Focus(DependencyObject focus, DependencyObject focused)
{
CultureInfo culture = null;
if (focus != null)
{
//
// Check the InputLanguageProperty of the focus element.
//
culture = (CultureInfo)focus.GetValue(InputLanguageProperty);
}
if ((culture == null) ||
(culture.Equals(CultureInfo.InvariantCulture)))
{
//
// If the focus element does not have InputLanguage property,
// we may need to restore the previous input language.
//
if (focused != null)
{
if ((_previousLanguageId != null) &&
(bool)focused.GetValue(RestoreInputLanguageProperty))
{
//
// set the current language id of source.
//
SetSourceCurrentLanguageId(_previousLanguageId);
}
_previousLanguageId = null;
}
}
else
{
// Cache the previous language id.
// _previousLanguageId can be clear during SetSourceCurrentLanguageId() because the call back
// ReportInputLanguageChanged() is called. We need to remember the current input language
// to update _previousLanguageId.
CultureInfo previousLanguageId = _source.CurrentInputLanguage;
//
// set the current language id of source.
//
SetSourceCurrentLanguageId(culture);
_previousLanguageId = previousLanguageId;
}
}
#endregion Internal methods
//------------------------------------------------------
//
// Internal Properties
//
//------------------------------------------------------
#region Internal Properties
internal IInputLanguageSource Source
{
get
{
return _source;
}
}
/// <summary>
/// This checks if there is two or more keyboard layouts.
/// </summary>
static internal bool IsMultipleKeyboardLayout
{
get
{
int count = SafeNativeMethods.GetKeyboardLayoutList(0, null);
return (count > 1);
}
}
#endregion Internal Properties
//------------------------------------------------------
//
// Private Methods
//
//------------------------------------------------------
private void SetSourceCurrentLanguageId(CultureInfo languageId)
{
if (_source == null)
{
throw new InvalidOperationException(SR.Get(SRID.InputLanguageManager_NotReadyToChangeCurrentLanguage));
}
_source.CurrentInputLanguage = languageId;
}
//------------------------------------------------------
//
// Private Events
//
//------------------------------------------------------
/// <summary>
/// This is an event when the input language is changed.
/// </summary>
private event InputLanguageEventHandler _InputLanguageChanged;
/// <summary>
/// This is an event when the input language is being changed.
/// </summary>
private event InputLanguageEventHandler _InputLanguageChanging;
//------------------------------------------------------
//
// Private Fields
//
//------------------------------------------------------
#region Private Fields
// the previous input language id this is used for restring input language at
// losing focus.
private CultureInfo _previousLanguageId;
// The reference to the source of input language.
private IInputLanguageSource _source;
#endregion Private Fields
}
/// <summary>
/// This is a delegate for InputLanguageChanged and
/// InputLanguageChanging events.
/// </summary>
public delegate void InputLanguageEventHandler(Object sender, InputLanguageEventArgs e);
}
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