Currently there are input issues, selection issues, caret issues when using IME input.
In the following example, the beginning of the first single line comment is considered a multiline comment start, but since nothing closes it, the entire text is tagged and colored as a comment.
// ***********************************************************************
// some other content here
// some other content here
// ***********************************************************************
public class TestClass
{
}
NullReferenceException thrown on opening the CompletionListWindow when RadSyntaxEditor is hosted in a non-WPF application (usually WinForms) and there are no WPF Application and MainWindow initialized.
This can happen if the RadSyntaxEditor for WPF is hosted in a WinForms application. In this scenario the System.Windows.Application.Current and its MainWindow are not initialized, which is what the IntelliPrompt positioning logic relies on.
Exception details:
System.NullReferenceException: 'Object reference not set to an instance of an object.'
> Telerik.Windows.Controls.SyntaxEditor.dll!Telerik.Windows.Controls.SyntaxEditor.UI.IntelliPromptBase.SetPosition(System.Windows.Point pointInScreen) Line 452 C# Telerik.Windows.Controls.SyntaxEditor.dll!Telerik.Windows.Controls.SyntaxEditor.UI.IntelliPromptBase.SetPosition(System.Windows.Point pointInEditorPresenter, System.Windows.Point pointAboveTheCaret) Line 442 C# Telerik.Windows.Controls.SyntaxEditor.dll!Telerik.Windows.Controls.SyntaxEditor.UI.IntelliPromptBase.SetPositionInView() Line 480 C# Telerik.Windows.Controls.SyntaxEditor.dll!Telerik.Windows.Controls.SyntaxEditor.UI.IntelliPromptBase.InitializeIntellisense() Line 401 C# Telerik.Windows.Controls.SyntaxEditor.dll!Telerik.Windows.Controls.SyntaxEditor.UI.IntelliPromptBase.Show(Telerik.Windows.Controls.SyntaxEditor.UI.CaretPosition caretStartPosition, Telerik.Windows.Controls.SyntaxEditor.UI.CaretPosition caretEndPositions) Line 211 C#
Telerik.Windows.Controls.SyntaxEditor.dll!Telerik.Windows.Controls.SyntaxEditor.UI.IntelliPromptBase.Show() Line 182 C#To work this around, you can initialize a new WPF application and MainWindow and create a hidden HwndSource for the MainWindow. This should happen before showing the WPF content in the WinForms application's code.
public Form1()
{
InitializeComponent();
new System.Windows.Application();
System.Windows.Application.Current.MainWindow = new System.Windows.Window();
var parameters = new HwndSourceParameters("HiddenHost")
{
Width = 1, Height = 1,
WindowStyle = unchecked((int)0x80000000) // WS_POPUP | WS_EX_NOACTIVATE
};
var hwndSource = new HwndSource(parameters);
hwndSource.RootVisual = System.Windows.Application.Current.MainWindow;
// other code here
ElementHost host = new ElementHost { Dock = DockStyle.Fill };
host.Child = wpfControl
this.Controls.Add(host);
}
The position of the popup representing the IntelliPrompt is wrong when shown on the monitor with the higher DPI scale, in a setup with two monitors with different DPI settings. For example, if one monitor has 100% DPI scale and the other 125%, the position of the popup will be wrong when the app is on the 125% monitor.
To work this around, use the Caret visual as the PlacementTarget for the popup and set its offsets to 0 after it is shown.
private void RadSyntaxEditor_PreviewKeyDown(object sender, System.Windows.Input.KeyEventArgs e)
{
if (KeyboardModifiers.IsControlDown && e.Key == Key.Space)
{
e.Handled = true;
var editor = (RadSyntaxEditor)sender;
CaretPosition startPosition = new CaretPosition(editor.CaretPosition);
CaretPosition endPosition = new CaretPosition(editor.CaretPosition);
editor.IntelliPrompts.CompletionListWindow.Show(startPosition, endPosition);
editor.IntelliPrompts.CompletionListWindow.HorizontalOffset = 0;
editor.IntelliPrompts.CompletionListWindow.VerticalOffset = 0;
}
}
private void RadSyntaxEditor_Loaded(object sender, System.Windows.RoutedEventArgs e)
{
var editor = (RadSyntaxEditor)sender;
var caret = editor.FindChildByType<Telerik.Windows.Controls.SyntaxEditor.UI.Caret>();
editor.IntelliPrompts.CompletionListWindow.PlacementTarget = caret;
editor.IntelliPrompts.CompletionListWindow.Placement = System.Windows.Controls.Primitives.PlacementMode.Bottom;
}
RadSyntaxEditor, while inside of a virtualized RadGridView, stealings focus immediately upon loading. It appears to do this automatically and there is no configuration to disabling. Meaning when scrolling in a RadGridView with virtualized rows, when a row with the RadSyntaxEditor materializes it will automatically steal focus from other elements.
This can be worked around using custom behavior that discards the first preview keyboard focus event that it receives.
private void onPreviewGotKeyboardFocus(object s, KeyboardFocusChangedEventArgs e)
{
if (!this.SuppressAutoFocus || _wasFocusSuppressed)
{
return;
}
_wasFocusSuppressed = true;
e.Handled = true;
}The offending line of code is this in RadSyntaxEditor.InitActiveEditorPresenter:
if (flag)
{
base.Dispatcher.BeginInvoke((Action)delegate
{
Focus();
});
}Request: Add a dependency property to allow opting-out of this default behavior. The above workaround works, but is a bit hacky for something that should probably be built-in.