Develop Reference

Element is already the child of another element when doesnt exist?

I'm trying to programatically create a button flyout, within my XAML I have:
<Page.Resources>
<Button x:Key="LaunchFlyout" Content="LAUNCH">
<Button.Flyout>
<Flyout Placement="Top">
<Grid Width="200" Height="200">
<StackPanel>
<Rectangle Fill="Red" Width="100" Height="100" />
<Rectangle Fill="Green" Width="100" Height="100" />
</StackPanel>
</Grid>
</Flyout>
</Button.Flyout>
</Button>
</Page.Resources>
Nested within grids I have:
<Grid x:Name="launchBtn_grid" Grid.Column="1">
</Grid>
And then in my code within the Page_Loaded method I have:
bool hasContainer = localSettings.Containers.ContainsKey("appStatus");
if (!hasContainer) {
Button button = (Button)this.Resources["LaunchFlyout"];
launchBtn_grid.Children.Add(button);
}
else {
Button button = new Button();
button.Content = "LAUNCH";
button.Click += launch_btn_Click;
launchBtn_grid.Children.Add(button);
}
When I debug this, it reaches the IF statement and reaches this line launchBtn_grid.Children.Add(button); and then I get this error Element is already the child of another element.
Does anyone understand why? I have already looked and they dont already exist so I don't understand why it is giving me this error. Does anyone know what I am doing wrong?

I'm not sure in what context/use case your are doing that, but it feels weird to me to have an actual control as a Resource (not a DataTemplate, Style, etc).
If you only want to have 1 button of the 2 different template, why not switch Visibility on the 2 instead of loading controls from your code behind ?
Going forward with the idea, just add both buttons in the Grid within your XAML and switch their Visibility according to the setting you read.
There is a BooleanToVisibilityConverter within the framework to help you with this.

remove a element from a StackPanel and add it to other StackPanel

is it possible to remove a item e.g. a TextBlock from a StackPanel and add it to a other StackPanel?
My XAML Code looks like this:
<StackPanel x:Name="PanelStack1" VerticalAlignment="Bottom" Margin="0,0,0,86">
<Rectangle x:Name="RecX" />
</StackPanel>
<StackPanel x:Name="PanelStack2" VerticalAlignment="Bottom" Margin="0,0,0,86" />
I want to move the RecX from the PanelStack1 to PanelStack2 via my C# Code. Is this possible?
This is just a small example, in my real code there are many elements which have to been moved.

Try this in your code behind:
PanelStack1.Children.Remove(RecX);
PanelStack2.Children.Add(RecX);

What is the equivalent way to use Bitmap,Graphics,PictureBox & BitmapCopy() in WPF?

I'll try to explain my problem clearly.
I have a working code in WinForms that has a Board (PictureBox) that shows an image thats generated from a list of users controls (win-forms) by the function UserControl.BitmapCopy() for each user control.
This process begins with a blank image (Graphic type), and for each user control I draw it in a specific location with the function BitmapCopy() of the user control.
The result is an image that looks like a real form (with buttons,labels,etc.), but it’s just an image.
Then I show this image in a picture Box.
Now I need to implement this code in WPF, but I can’t generate an image of each user control with BitmapCopy().
I found this code that does it, so now I can generate a bitmap for each user control, but I don’t know what is the best way to create the Big Board that eventually shows a bitmap that has all the user controls images inside it, in different locations.
I would appreciate any help.

This is the equivalent in WPF:
<Window x:Class="MiscSamples.VisualBrush"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="VisualBrush" Height="300" Width="300" x:Name="Window">
<StackPanel>
<TextBlock Text="Hi, Im a Window!"/>
<TextBox Text="This is a TextBox"/>
<Slider Width="200"/>
</StackPanel>
<Window.ToolTip>
<ToolTip DataContext="{Binding PlacementTarget, RelativeSource={RelativeSource Self}}">
<Grid Height="400" Width="400">
<Grid.Background>
<VisualBrush Visual="{Binding}"/>
</Grid.Background>
</Grid>
</ToolTip>
</Window.ToolTip>
</Window>
The Window's ToolTip consists of a grid painted with VisualBrush whose Visual is the Window itself. It looks like this:
As you can see, Exactly 0 lines of C# code are required to achieve the same in WPF.

Bing Maps (Silverlight) maps - specifying canvas to be at foreground through XAML

Below is the XAML code i have for a Bing Maps Silverlight weather related implementation.
Here is what i am trying to do:
Have a bing maps with several (over 100) pushpins- on mouseover - show a contentpopup (canvas=myPopup) below. Simple enough.
Everything works fine - however, when mypopup displays on mouseover, it is not on the foreground (the other pins appear on top of the contentpopup) - hence making it not very readable.
Question:
How do i specifiy the myPopup canvas specified in XAML below to always appear in the foreground, i.e. top most of the Bing Maps silverlight control when a user views it on mouseover.
Thanks!
<Grid x:Name="LayoutRoot" Background="White">
<m:Map x:Name="GlobalMap" Mode="Road" Center="15,7" ZoomLevel="2" CredentialsProvider="{StaticResource MyCredentials}" Margin="-70,-40,-100,-72">
<m:MapLayer x:Name="myLayer">
<Canvas x:Name="myPopup" Visibility="Collapsed" Opacity="1">
<Rectangle x:Name="myPopupRectangle" Fill="White" Canvas.Left="0" Canvas.Top="0" Height="100"
Width="100" RadiusX="15" RadiusY="15"/>
<StackPanel Canvas.Left="8" Canvas.Top="8">
<TextBlock x:Name="myPopupTexts" FontSize="5" Width="100">
</TextBlock>
</StackPanel>
</Canvas>
</m:MapLayer>
</m:Map>
</Grid>

Try adding Canvas.ZIndex to the MapLayer element, give it a large value like 200 or add your push pins to another MapLayer (rather than adding the pins directly to the map) that appears ahead of this popup layer in document order.

I did something similar to this, but took a different approach. What I did was create a custom pushpin template and create a PopUp within the template.
When the user hovers over the pushpin, the popup is displayed. Using the PopUp will solve your problem, since the control will automatically position it on top of everything. Try wrapping the Canvas in a PopPup and see if that works.
hth

ControlTemplate

I am quite new to WPF and have a basic question :
Assume the following is xaml declaration in my xaml file
<ContentControl x:Name="interactionActivityContent" Loaded="interactionActivityContent_Loaded">
<shapes:BaseShape.DragThumbTemplate >
<ControlTemplate x:Name="interactionActivityTemplate">
<Grid AllowDrop="True" x:Name="GridTest" >
<Rectangle Name="Interaction" Fill="Yellow" Stroke="Green" StrokeThickness="2" IsHitTestVisible="True" AllowDrop="True"></Rectangle>
<local:DesignerCanvas x:Name="ActivitiesCanvasArea" Margin="1,1,1,1" IsHitTestVisible="True" AllowDrop="True" Background="Blue"></local:DesignerCanvas>
</Grid>
</ControlTemplate>
</shapes:BaseShape.DragThumbTemplate>
*shapes:BaseShape.DragThumbTemplate is coming from some different class.
*DesignerCanvas is my own custom canvas for which I want to set value at run time.
How can I access ActivitiesCanvasArea in my C# code from the code behind file?
Do I need to change the way xaml is declared. I need to apply DragThumbTemplate to my grid so that I can move around grid on main screen.

From http://blogs.msdn.com/b/wpfsdk/archive/2007/03/16/how-do-i-programmatically-interact-with-template-generated-elements-part-i.aspx
If you need to find a named element in the ControlTemplate of myButton1, like the Grid, you can use Template.FindName like so:
// Finding the grid generated by the ControlTemplate of the Button
Grid gridInTemplate = (Grid)myButton1.Template.FindName("grid", myButton1);