I am trying to create a "debug" TextBlock, in the sense it is just like a MessageBox, but doesn't interrupt like it. Rather, it is like a statusbar, which gives output information silently. Here is my current code
private void Debug(string data)
{
TextBlock tb = componentContainer.FindName("Debugbox") as TextBlock;
if (tb == null)
{
MessageBox.Show("yo");
tb = new TextBlock() {Foreground = Brushes.Orange };
if (NameScope.GetNameScope(tb) == null)
NameScope.SetNameScope(tb, new NameScope());
componentContainer.RegisterName("Debugbox", tb);
componentContainer.Children.Add(tb);
}
tb.Text = data;
}
However, it is giving me "No NameScope found to register the Name". I tried replacing
componentContainer.RegisterName("Debugbox", tb);
with
Namescope.GetNameScope(tb).RegisterName("Debugbox", tb);
and it works well. But if this function is used multiple times, the TextBlock is simply overwritten which makes the required output hard to see.
NOTE : componentContainer is a Canvas
Does anyone know what I am doing wrong? Or is there any better way to do something similar?
Why not simply keep the TextBlock instance in a private field:
private TextBlock debugBox;
private void Debug(string data)
{
if (debugBox == null)
{
debugBox = new TextBlock { Foreground = Brushes.Orange };
componentContainer.Children.Add(debugBox);
}
debugBox.Text = data;
}
Related
Ok... this has me stumped. I've overridden OnContentTemplateChanged in my UserControl subclass. I'm checking that the value passed in for newContentTemplate does in fact equal this.ContentTemplate (it does) yet when I call this...
var textBox = this.ContentTemplate.FindName("EditTextBox", this);
...it throws the following exception...
"This operation is valid only on elements that have this template applied."
Per a commenter in another related question, he said you're supposed to pass in the content presenter for the control, not the control itself, so I then tried this...
var cp = FindVisualChild<ContentPresenter>(this);
var textBox = this.ContentTemplate.FindName("EditTextBox", cp);
...where FindVisualChild is just a helper function used in MSDN's example (see below) to find the associated content presenter. While cp is found, it too throws the same error. I'm stumped!!
Here's the helper function for reference...
private TChildItem FindVisualChild<TChildItem>(DependencyObject obj)
where TChildItem : DependencyObject {
for(int i = 0 ; i < VisualTreeHelper.GetChildrenCount(obj) ; i++) {
var child = VisualTreeHelper.GetChild(obj, i);
if(child is TChildItem typedChild) {
return typedChild;
}
else {
var childOfChild = FindVisualChild<TChildItem>(child);
if(childOfChild != null)
return childOfChild;
}
}
return null;
}
Explicitly applying the template before calling the FindName method will prevent this error.
this.ApplyTemplate();
As John pointed out, the OnContentTemplateChanged is being fired before it is actually applied to the underlying ContentPresenter. So you'd need to delay your call to FindName until it is applied. Something like:
protected override void OnContentTemplateChanged(DataTemplate oldContentTemplate, DataTemplate newContentTemplate) {
base.OnContentTemplateChanged(oldContentTemplate, newContentTemplate);
this.Dispatcher.BeginInvoke((Action)(() => {
var cp = FindVisualChild<ContentPresenter>(this);
var textBox = this.ContentTemplate.FindName("EditTextBox", cp) as TextBox;
textBox.Text = "Found in OnContentTemplateChanged";
}), DispatcherPriority.DataBind);
}
Alternatively, you may be able to attach a handler to the LayoutUpdated event of the UserControl, but this may fire more often than you want. This would also handle the cases of implicit DataTemplates though.
Something like this:
public UserControl1() {
InitializeComponent();
this.LayoutUpdated += new EventHandler(UserControl1_LayoutUpdated);
}
void UserControl1_LayoutUpdated(object sender, EventArgs e) {
var cp = FindVisualChild<ContentPresenter>(this);
var textBox = this.ContentTemplate.FindName("EditTextBox", cp) as TextBox;
textBox.Text = "Found in UserControl1_LayoutUpdated";
}
The ContentTemplate isn't applied to the ContentPresenter until after that event. While the ContentTemplate property is set on the control at that point, it hasn't been pushed down to bindings internal to the ControlTemplate, like the ContentPresenter's ContentTemplate.
What are you ultimately trying to do with the ContentTemplate? There might be a better overall approach to reach your end goal.
In this case when user click some UIElement I want this element yo be surrounded by dashed border. If there is some other object surrounded then this code removes it first.
Everything is fine but "private void activateElem" fires twice and I have no idea why. Maybe somebody can help, I really have no more ideas.
Anybody knows some ideas to debug issues like this? Maybe there is some way to print out all events queue. There is silverlight spy but I think it doesn't work for windows phone 7.
My code:
public class ManipulationEngine
{
private Canvas sheet;
private static FrameworkElement current_active_element;
public ManipulationEngine(Canvas sheet)
{
this.sheet = sheet;
foreach (FrameworkElement elem in sheet.Children)
{
elem.MouseLeftButtonUp += new MouseButtonEventHandler(activateElem);
}
}
private void activateElem(object sender, MouseButtonEventArgs e)
{
FrameworkElement elem = sender as FrameworkElement;
if (current_active_element != null)
{
desactivateElem();
}
Grid grid = new Grid();
Rectangle recentagle = new Rectangle();
grid.SetValue(Canvas.TopProperty, (double)elem.GetValue(Canvas.TopProperty) - 10);
grid.SetValue(Canvas.LeftProperty, (double)elem.GetValue(Canvas.LeftProperty) - 10);
DoubleCollection stroke = new DoubleCollection();
stroke.Add(4);
stroke.Add(2);
recentagle.StrokeDashArray = stroke;
grid.Children.Add(recentagle);
sheet.Children.Remove(elem);
elem.Margin = new Thickness(10);
grid.Children.Add(elem);
sheet.Children.Add(grid);
current_active_element = elem;
}
private void desactivateElem()
{
if (current_active_element != null)
{
Grid grid = VisualTreeHelper.GetParent(current_active_element) as Grid;
grid.Children.Remove(current_active_element);
sheet.Children.Remove(grid);
current_active_element.SetValue(Canvas.TopProperty, (double)grid.GetValue(Canvas.TopProperty) + 10);
current_active_element.SetValue(Canvas.LeftProperty, (double)grid.GetValue(Canvas.LeftProperty) + 10);
current_active_element.Margin = new Thickness(0);
sheet.Children.Add(current_active_element);
current_active_element = null;
}
}
I'd really advise looking into the Parts and States model. You may be able to do this with a button, or perhaps a radio button.
Usually if you're coding changes to the visual tree, you're not doing it right.
Karen Corby dealt with this very clearly at MIX08, take a look!
http://archive.visitmix.com/blogs/2008Sessions/T20/
Luke
sorry for my bad english... The default for a RichTextBox content is to inherit the Foreground color from the RichTextBox itself. That's nice, but if I set a specific Foreground color to some part of my text, that part does not inherit the Foreground anymore, obviously. How can I make my "colored" text inherit the Foreground again? I'm trying to do something like the "Automatic" color from Office Word but after I have set a specific color to a TextRange, I do not know how to unset it :/
TextRange.ClearAllProperties() does what I need, but also erases other properties like FontSize and FontFamily...
TextRange.ApplyPropertyValue(ForegroundProperty, DependencyProperty.UnsetValue) also does not do the trick...
You can also unset it by setting the property to null (this worked for me clearing out the background, for example removing highlighting)
TextRange.ApplyPropertyValue(TextElement.BackgroundProperty, null);
This seemed almost impossible to achieve since there is no "RemovePropertyValue" method. I also tried with span and got the same exception as you did so I made a method that collects all the Paragraphs within the TextRange and made a span for each separetly.. less than ideal, I know.. Anyway, it works for a small example but might be pretty hard to work with for something more complex.
private List<Span> m_spanList = new List<Span>();
private void c_setForegroundButton_Click(object sender, RoutedEventArgs e)
{
TextPointer textPointerStart = c_richTextBox1.Selection.Start;
TextPointer textPointerEnd = c_richTextBox1.Selection.End;
TextRange textRange = new TextRange(textPointerStart, textPointerEnd);
SetForeground(textRange);
}
private void c_clearForegroundButton_Click(object sender, RoutedEventArgs e)
{
foreach (Span span in m_spanList)
{
span.ClearValue(Span.ForegroundProperty);
}
}
public void SetForeground(TextRange textRange)
{
List<Paragraph> spannedParagraphs = new List<Paragraph>();
if (textRange.Start.Paragraph != null)
{
TextRange curRange = null;
Block cur = textRange.Start.Paragraph;
do
{
spannedParagraphs.Add(cur as Paragraph);
// Get next range
curRange = new TextRange(cur.ContentStart, cur.ContentEnd);
} while ((textRange.End.Paragraph == null || !curRange.Contains(textRange.End.Paragraph.ContentEnd)) && (cur = cur.NextBlock) != null);
}
if (spannedParagraphs.Count == 1)
{
Span span = new Span(c_richTextBox1.Selection.Start, c_richTextBox1.Selection.End);
span.Foreground = Brushes.Red;
m_spanList.Add(span);
}
else
{
for (int i = 0; i < spannedParagraphs.Count; i++)
{
if (i == spannedParagraphs.Count - 1)
{
Paragraph paragraph = spannedParagraphs[i];
// For some reason I get an exception here when I try this..
//m_span = new Span(paragraph.ElementStart, c_richTextBox1.Selection.End);
c_richTextBox1.Selection.Select(paragraph.ElementStart, c_richTextBox1.Selection.End);
Span span = new Span(c_richTextBox1.Selection.Start, c_richTextBox1.Selection.End);
span.Foreground = Brushes.Red;
m_spanList.Add(span);
}
else if (i == 0)
{
Paragraph paragraph = spannedParagraphs[i];
Span span = new Span(c_richTextBox1.Selection.Start, paragraph.ElementEnd);
span.Foreground = Brushes.Red;
m_spanList.Add(span);
}
else
{
Paragraph paragraph = spannedParagraphs[i];
Span span = new Span(paragraph.ElementStart, paragraph.ElementEnd);
span.Foreground = Brushes.Red;
m_spanList.Add(span);
}
}
}
}
If you look at the code of method TextRange.ApplyPropertyValue in the .NET Reference Source, you'll see that in the end it calls DependencyObject.SetValue on a collection of Inlines and Blocks, and DependencyObject.SetValue treats the value DependencyProperty.UnsetValue specially by effectively clearing the local value for the property.
The problem is that they didn't think of that when implementing TextRange.ApplyPropertyValue: it checks the passed property value against the property type, and in case of a reference type, it makes sure the passed value is either null or inherits from the same class, thus preventing us from passing DependencyProperty.UnsetValue.
One solution I found to implement a way of clearing local values of a TextRange for dependency properties of a reference type is the following:
// We declare a marker brush to be detected later in the TextRange.
var markerBrush = new SolidColorBrush();
// First we ask the TextRange implementation to set our marker brush on its content.
// Using ApplyPropertyValue here takes care of splitting inlines when necessary to make
// sure that only the selected text gets affected.
range.ApplyPropertyValue(TextElement.ForegroundProperty, markerBrush);
// Now, we search the text range for every Inline that has our brush set as the foreground
// brush, and we clear the Foreground dependency property.
var position = range.Start;
while (position != null && range.Contains(position))
{
if (position.GetPointerContext(LogicalDirection.Backward) == TextPointerContext.ElementStart &&
position.Parent is Inline inline &&
inline.ReadLocalValue(TextElement.ForegroundProperty) == _foregroundClearBrush)
inline.ClearValue(TextElement.ForegroundProperty);
position = position.GetNextContextPosition(LogicalDirection.Forward);
}
I have a WPF application on which the user can paste some data from Word inside a RichTextBox... but if that word data has an image, I need to remove it, how can I accomplish that?
Since the FlowDocument is xml, maybe doing some linq magic could do it, but I don't know how.
There is a tool called WordtoXAML Converter (http://wordtoxaml.codeplex.com). You can use that to convert your Word document contents to XAML, use regular expression matching to identify the images and then strip them out.
The following code will do what you want. While it can be a bit wasteful (it looks through the entire document instead of just the bit that was just pasted), it is the only way to do it, as sometimes the RichTextBox is inaccurate when it indicates the recently painted range:
public class MyTextBox : RichTextBox
{
public MyTextBox()
{
CommandBindings.Add(new CommandBinding(ApplicationCommands.Paste, Paste));
}
protected virtual void Paste(object sender, ExecutedRoutedEventArgs e)
{
Paste();
foreach (var image in FindImages())
{
if (image.SiblingInlines != null)
{
image.SiblingInlines.Remove(image);
}
}
}
IEnumerable<InlineUIContainer> FindImages()
{
var result = new List<InlineUIContainer>();
var blocks = Document.Blocks;
for (TextPointer position = blocks.FirstBlock.ElementStart; position != null && position.CompareTo(blocks.LastBlock.ElementEnd) != 1; position = position.GetNextContextPosition(LogicalDirection.Forward))
{
InlineUIContainer element = position.Parent as InlineUIContainer;
if (element != null && element.Child is Image)
{
result.Add(element);
}
}
return result;
}
}
I am creating controls (say button) on a grid. I want to create a connecting line between controls.
Say you you do mousedown on one button and release mouse over another button. This should draw a line between these two buttons.
Can some one help me or give me some ideas on how to do this?
Thanks in advance!
I'm doing something similar; here's a quick summary of what I did:
Drag & Drop
For handling the drag-and-drop between controls there's quite a bit of literature on the web (just search WPF drag-and-drop). The default drag-and-drop implementation is overly complex, IMO, and we ended up using some attached DPs to make it easier (similar to these). Basically, you want a drag method that looks something like this:
private void onMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
UIElement element = sender as UIElement;
if (element == null)
return;
DragDrop.DoDragDrop(element, new DataObject(this), DragDropEffects.Move);
}
On the target, set AllowDrop to true, then add an event to Drop:
private void onDrop(object sender, DragEventArgs args)
{
FrameworkElement elem = sender as FrameworkElement;
if (null == elem)
return;
IDataObject data = args.Data;
if (!data.GetDataPresent(typeof(GraphNode))
return;
GraphNode node = data.GetData(typeof(GraphNode)) as GraphNode;
if(null == node)
return;
// ----- Actually do your stuff here -----
}
Drawing the Line
Now for the tricky part! Each control exposes an AnchorPoint DependencyProperty. When the LayoutUpdated event is raised (i.e. when the control moves/resizes/etc), the control recalculates its AnchorPoint. When a connecting line is added, it binds to the DependencyProperties of both the source and destination's AnchorPoints. [EDIT: As Ray Burns pointed out in the comments the Canvas and grid just need to be in the same place; they don't need to be int the same hierarchy (though they may be)]
For updating the position DP:
private void onLayoutUpdated(object sender, EventArgs e)
{
Size size = RenderSize;
Point ofs = new Point(size.Width / 2, isInput ? 0 : size.Height);
AnchorPoint = TransformToVisual(node.canvas).Transform(ofs);
}
For creating the line class (can be done in XAML, too):
public sealed class GraphEdge : UserControl
{
public static readonly DependencyProperty SourceProperty = DependencyProperty.Register("Source", typeof(Point), typeof(GraphEdge), new FrameworkPropertyMetadata(default(Point)));
public Point Source { get { return (Point) this.GetValue(SourceProperty); } set { this.SetValue(SourceProperty, value); } }
public static readonly DependencyProperty DestinationProperty = DependencyProperty.Register("Destination", typeof(Point), typeof(GraphEdge), new FrameworkPropertyMetadata(default(Point)));
public Point Destination { get { return (Point) this.GetValue(DestinationProperty); } set { this.SetValue(DestinationProperty, value); } }
public GraphEdge()
{
LineSegment segment = new LineSegment(default(Point), true);
PathFigure figure = new PathFigure(default(Point), new[] { segment }, false);
PathGeometry geometry = new PathGeometry(new[] { figure });
BindingBase sourceBinding = new Binding {Source = this, Path = new PropertyPath(SourceProperty)};
BindingBase destinationBinding = new Binding { Source = this, Path = new PropertyPath(DestinationProperty) };
BindingOperations.SetBinding(figure, PathFigure.StartPointProperty, sourceBinding);
BindingOperations.SetBinding(segment, LineSegment.PointProperty, destinationBinding);
Content = new Path
{
Data = geometry,
StrokeThickness = 5,
Stroke = Brushes.White,
MinWidth = 1,
MinHeight = 1
};
}
}
If you want to get a lot fancier, you can use a MultiValueBinding on source and destination and add a converter which creates the PathGeometry. Here's an example from GraphSharp. Using this method, you could add arrows to the end of the line, use Bezier curves to make it look more natural, route the line around other controls (though this could be harder than it sounds), etc., etc.
See also
http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/dd246675-bc4e-4d1f-8c04-0571ea51267b
http://www.codeproject.com/KB/WPF/WPFDiagramDesigner_Part1.aspx
http://www.codeproject.com/KB/WPF/WPFDiagramDesigner_Part2.aspx
http://www.codeproject.com/KB/WPF/WPFDiagramDesigner_Part3.aspx
http://www.codeproject.com/KB/WPF/WPFDiagramDesigner_Part4.aspx
http://www.syncfusion.com/products/user-interface-edition/wpf/diagram
http://www.mindscape.co.nz/products/wpfflowdiagrams/