mcs/class/referencesource/System.Activities.Presentation/System.Activities.Presentation/System/Activities/Presentation/View/VBIdentifierDesigner.xaml.cs

   1 //----------------------------------------------------------------
   2 // Copyright (c) Microsoft Corporation.  All rights reserved.
   3 //----------------------------------------------------------------
   4
   5 namespace System.Activities.Presentation.View
   6 {
   7     using System;
   8     using System.Collections.Generic;
   9     using System.Linq;
  10     using System.Text;
  11     using System.Windows;
  12     using System.Windows.Controls;
  13     using System.Windows.Data;
  14     using System.Windows.Documents;
  15     using System.Windows.Input;
  16     using System.Windows.Media;
  17     using System.Windows.Media.Imaging;
  18     using System.Windows.Navigation;
  19     using System.Windows.Shapes;
  20     using System.Activities.Presentation.View;
  21     using System.ComponentModel;
  22     using System.Windows.Automation.Peers;
  23     using System.Xml.Linq;
  24     using System.Reflection;
  25
  26     partial class VBIdentifierDesigner : UserControl
  27     {
  28         public static readonly DependencyProperty IdentifierProperty =
  29             DependencyProperty.Register("Identifier", typeof(VBIdentifierName), typeof(VBIdentifierDesigner), new UIPropertyMetadata(OnIdentifierChanged));
  30
  31         public static readonly DependencyProperty NameStringProperty =
  32             DependencyProperty.Register("NameString", typeof(string), typeof(VBIdentifierDesigner), new UIPropertyMetadata(null, null, OnNameChanging));
  33
  34         public static readonly DependencyProperty IsReadOnlyProperty =
  35             DependencyProperty.Register("IsReadOnly", typeof(bool), typeof(VBIdentifierDesigner));
  36
  37         public event PropertyChangedEventHandler TextBoxPropertyChanged;
  38
  39         TextBox textBox;
  40         bool isInternalChange;
  41         bool checkAgainstXaml;
  42
  43         public VBIdentifierName Identifier
  44         {
  45             get { return (VBIdentifierName)GetValue(IdentifierProperty); }
  46             set { SetValue(IdentifierProperty, value); }
  47         }
  48
  49         public string NameString
  50         {
  51             get { return (string)GetValue(NameStringProperty); }
  52             set { SetValue(NameStringProperty, value); }
  53         }
  54
  55         public bool IsReadOnly
  56         {
  57             get { return (bool)GetValue(IsReadOnlyProperty); }
  58             set { SetValue(IsReadOnlyProperty, value); }
  59         }
  60
  61         internal TextBox IdentifierTextBox
  62         {
  63             get
  64             {
  65                 return this.textBox;
  66             }
  67             set
  68             {
  69                 if (value != this.textBox)
  70                 {
  71                     this.textBox = value;
  72                     if (this.TextBoxPropertyChanged != null)
  73                     {
  74                         this.TextBoxPropertyChanged(this, new PropertyChangedEventArgs("IdentifierTextBox"));
  75                     }
  76                 }
  77             }
  78         }
  79
  80         public VBIdentifierDesigner()
  81         {
  82             InitializeComponent();
  83             this.Loaded += (s, e) =>
  84                 {
  85                     //when designer gets loaded, get its identifier binding expression with parent control
  86                     var binding = this.GetBindingExpression(VBIdentifierDesigner.IdentifierProperty);
  87                     if (null != binding && null != binding.ParentBinding)
  88                     {
  89                         //if one exists - define update source exception filter
  90                         binding.ParentBinding.UpdateSourceExceptionFilter = this.OnBindingException;
  91                     }
  92                 };
  93         }
  94
  95
  96         void OnTextBoxLoaded(object sender, RoutedEventArgs e)
  97         {
  98             this.IdentifierTextBox = sender as TextBox;
  99             this.IdentifierTextBox.LostKeyboardFocus += this.OnTextBoxLostKeyboardFocus;
 100         }
 101
 102         void OnTextBoxLostKeyboardFocus(object sender, KeyboardFocusChangedEventArgs e)
 103         {
 104             if (this.IdentifierTextBox.IsFocused)
 105             {
 106                 DependencyObject focusScope = FocusManager.GetFocusScope(this.IdentifierTextBox);
 107                 FocusManager.SetFocusedElement(focusScope, this);
 108             }
 109         }
 110
 111         void OnTextBoxUnloaded(object sender, RoutedEventArgs e)
 112         {
 113             TextBox textBox = sender as TextBox;
 114             textBox.LostKeyboardFocus -= this.OnTextBoxLostKeyboardFocus;
 115             this.IdentifierTextBox = null;
 116         }
 117
 118         object OnBindingException(object sender, Exception err)
 119         {
 120             //whenever exception occurs, allow ValidationException to be rethrown - this exception is needed to revert invalid value
 121             if (err is TargetInvocationException && err.InnerException is ValidationException || err is ValidationException)
 122             {
 123                 throw FxTrace.Exception.AsError( err.InnerException ?? err );
 124             }
 125             //simply return null - we don't use error template for this control
 126             return null;
 127         }
 128
 129         static object OnNameChanging(DependencyObject sender, object newValue)
 130         {
 131             var ctrl = (VBIdentifierDesigner)sender;
 132             //before allowing new value to be assigned to property, check if it passes validation
 133             return ctrl.OnNameChanging(ctrl.NameString, (string)newValue);
 134         }
 135
 136         object OnNameChanging(string oldName, string newName)
 137         {
 138             string result = newName;
 139             if (!this.isInternalChange)
 140             {
 141                 try
 142                 {
 143                     this.isInternalChange = true;
 144                     //try to create new Identifier - if this call succeds, set the new value to a property
 145                     this.Identifier = new VBIdentifierName(this.checkAgainstXaml) { IdentifierName = newName };
 146                 }
 147                 catch (ValidationException)
 148                 {
 149                     //in case of validation exception - do not allow new invalid value to be set
 150                     result = oldName;
 151                     //if text box is still visible - refresh its Text property to old value
 152                     if (null != this.textBox)
 153                     {
 154                         var binding = this.textBox.GetBindingExpression(TextBox.TextProperty);
 155                         binding.UpdateTarget();
 156                     }
 157                 }
 158                 finally
 159                 {
 160                     this.isInternalChange = false;
 161                 }
 162             }
 163             return result;
 164         }
 165
 166         static void OnIdentifierChanged(DependencyObject sender, DependencyPropertyChangedEventArgs args)
 167         {
 168             (sender as VBIdentifierDesigner).OnIdentifierChanged();
 169         }
 170
 171         void OnIdentifierChanged()
 172         {
 173             if (!this.isInternalChange && null != this.Identifier)
 174             {
 175                 this.isInternalChange = true;
 176                 this.NameString = this.Identifier.IdentifierName;
 177                 this.isInternalChange = false;
 178                 this.checkAgainstXaml = this.Identifier.CheckAgainstXaml;
 179             }
 180         }
 181
 182         protected override AutomationPeer OnCreateAutomationPeer()
 183         {
 184             return new VBIdentiferDesignerAutomationPeer(this);
 185         }
 186     }
 187
 188     class VBIdentiferDesignerAutomationPeer : UIElementAutomationPeer
 189     {
 190         public VBIdentiferDesignerAutomationPeer(VBIdentifierDesigner owner)
 191             : base(owner)
 192         {
 193         }
 194
 195         protected override string GetItemStatusCore()
 196         {
 197             VBIdentifierDesigner vbIdentifierDesigner = this.Owner as VBIdentifierDesigner;
 198             if (vbIdentifierDesigner != null)
 199             {
 200                 VBIdentifierName vbIdentifier = vbIdentifierDesigner.Identifier;
 201                 if (vbIdentifier != null)
 202                 {
 203                     XElement itemStatus = new XElement("VBIdentifierStatus",
 204                         new XAttribute("Status", vbIdentifier.IsValid ? "Valid" : "Invalid"),
 205                         new XAttribute("WarningMessage", vbIdentifier.ErrorMessage));
 206                     return itemStatus.ToString();
 207                 }
 208             }
 209             return base.GetItemStatusCore();
 210         }
 211     }
 212 }