I am using a ListBox with a DataTemplate to create the below map legend. I would like to get the ListBox to have a transparent background (where it is now white) and the ListItems to retain their existing white background. The two legends would then appear to float with a transparent gap between.
I have tried setting the ListBox background with a SolidBrush set to 0 opacity but that doesn't seem to work. I understand that items in the tree cannot have transparency that is less than items above in the tree. Is that my issue and how do I resolve?
Thanks
alt text http://www.freeimagehosting.net/uploads/659cd194e7.png
You can set the Background to {x:Null}.
Did you try setting the background color of the ListBox to "Transparent" (literally)?
Here is some code that worked for me:
<Window x:Class="WpfApplication3.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525" Background="Blue">
<Grid>
<ListBox x:Name="ListBox1" Margin="12,25,114,97" Background="#00E51A1A">
<ListBox.ItemTemplate>
<DataTemplate>
<Grid Margin="4" Height="20" Width="100" Background="Yellow" />
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
</Window>
Related
Lately I found out that it seems to matter a lot where "Opacity" is set in WPF:
Option 1: By setting Brush Color with #ARGB
Option 2: By setting Opacity as Property of Brush
Option 3: By setting Opacity directly on the Control
Screenshot of results:
Different ways to produce opacity
While options 1 & 2 appear to produce the same results, option 3 seems to be similar to what web browsers produce.
Now my question is, can opacity values set on brushes (WPF) somehow be converted to opacity values of "color" in web browsers? Because setting a control´s opacity seems not the best way to go for "coloring" layout elements.
Here´s the XAML layout which produces the output as described & shown above:
<Window x:Class="Color_Test.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:Color_Test"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="800">
<Window.Resources>
<ResourceDictionary>
<SolidColorBrush x:Key="Brush_Test_Bg" Color="#25252B" />
<SolidColorBrush x:Key="Brush_Test_Fg_OpacityByArgb" Color="#5cffffff" />
<SolidColorBrush x:Key="Brush_Test_Fg_OpacityByPropertyOnBrush" Color="#ffffff" Opacity=".36"/>
<SolidColorBrush x:Key="Brush_Test_Fg_OpacityByPropertyOnControl" Color="#ffffff"/>
</ResourceDictionary>
</Window.Resources>
<Grid Background="{StaticResource Brush_Test_Bg}">
<StackPanel VerticalAlignment="Center" HorizontalAlignment="Center">
<TextBlock Text="1: Opacity by Brush Color='#5cffffff'" FontSize="24" FontWeight="Bold" Foreground="{StaticResource Brush_Test_Fg_OpacityByArgb}" />
<TextBlock Text="2: Opacity by Brush Color='#ffffff' and Brush Opacity='.36'" FontSize="24" FontWeight="Bold" Foreground="{StaticResource Brush_Test_Fg_OpacityByPropertyOnBrush}" />
<TextBlock Text="3: Opacity by Brush Color='#ffffff' and TextBlock Opacity='.36'" FontSize="24" FontWeight="Bold" Foreground="{StaticResource Brush_Test_Fg_OpacityByPropertyOnControl}" Opacity=".36" />
</StackPanel>
</Grid>
Also, here´s a Codepen-Link to the web-output for comparison.
For completion: I tried TextOptions.TextFormattingMode="Display" inside the wpf layout which produces only different (uncontrollable) results.
I have the following code in WPF XAML:
<Window x:Class="WPFDemo.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<StackPanel>
<Button Content="Hello World" Width="Auto" Height="Auto"></Button>
</StackPanel>
</Window>
I have set the width and height of the Button to "Auto" but still it stretches the complete horizontal width. What am I doing wrong? I do not want to provide a hardcoded values for the width and height!
You are using the wrong kind of container control. The StackPanel does not resize its contents. Try a Grid instead:
<Grid>
<Button Content="Hello" HorizontalAlignment="Center" VerticalAlignment="Center" />
</Grid>
Also, you don't need to set the Width and Height to "Auto", as the default values will enable the Button to stretch to fill its parent container (depending on the container control). Please see the Panels Overview page on MSDN for more help with the differences between the various container controls in WPF.
As Sheridan said, you do not need to set Width and Height to "Auto".
Your problem is that the default alignment of the StackPanel content is "Stretch".
So just set the HorizontalAlignment property of your button to "Left" or "Right".
<Window x:Class="WPFDemo.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow">
<Grid>
<Button Content="Hello World" Width="Auto" Height="Auto"></Button>
</Grid>
</Window>
In my example wpf app I've added one button and one popup to the window. The button is in the bottom right corner and the popup has set "PlacementTarget" property to it and "Placement" set to top. The popup consists of one very long textblock.
What I expect this popup will behave is not to go outside of the window and therefore automatically set his "HorizontalOffset" to the appropriate value, but the popup behaves against my intentions.
Here's my xaml file:
<Window
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:WpfApplication1" x:Name="window" x:Class="WpfApplication1.MainWindow"
Title="MainWindow" Height="350" Width="525">
<Window.Resources>
<local:Converters x:Key="Converters"/>
</Window.Resources>
<Grid>
<Button x:Name="button" Content="Button" VerticalAlignment="Bottom" Width="75" HorizontalAlignment="Right"/>
<Popup Placement="Top" PlacementTarget="{Binding ElementName=button, Mode=OneWay}" IsOpen="True">
<TextBlock TextWrapping="Wrap" Text="aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa" Background="White"/>
</Popup>
</Grid>
Do anyone know how to fix it?
I've read that this should be default popup behavior to take care of going out of the boundaries, but not in my case. Thanks in advance.
Have you tried to set the width of the Popup or Textblock ?
Sorry, I can't write this poor answer as a comment..
I am new to WPF and i can not figure some things out. I just started an new project and i wanted to make a StackPanel because i saw that on a tutorial. But now i've implemented the StackPanel and i get 2 errors.
The object 'Window' already has a child and cannot add 'StackPanel'. 'Window' can accept only one child. Line 9 Position 116.
The property 'Content' is set more than once.
Can someone explain to me what i am doeing wrong.
This is my code:
<Window x:Class="CheckDatabase.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="CheckDatabase" Height="350" Width="525">
<Grid Margin="10,80,10,10" >
<TextBox TextWrapping="Wrap"/>
</Grid>
<StackPanel Grid.Column="0" Grid.Row="0" HorizontalAlignment="Left" Name="ButtonPanel" VerticalAlignment="Top">
<Button Margin="0,10,0,10">Button 1</Button>
<Button Margin="0,10,0,10">Button 2</Button>
</StackPanel>
Thanks in advance
A Window can only contain one child. However, your Window contains both a Grid and a StackPanel.
To fix this you need to put the StackPanel inside the grid (if that is the intention) or wrap both the Grid and the StackPanel inside another panel that positions the two elements in the way you want.
Some Controls like Window can only have a single child. You will have to remove the Grid or either nest another Grid arround your Grid and Stackpanel.
Example:
<Grid x:Name="outerGrid">
<Grid x:Name="innerGrid"></Grid>
<StackPanel x:Name="innerStackPanel></StackPanel>
</Grid>
Window is a ContentControl and hence can have only one Content. You can do the following to have the expected layout
<Window x:Class="CheckDatabase.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="CheckDatabase" Height="350" Width="525">
<StackPanel>
<Grid Margin="10,80,10,10" >
<TextBox TextWrapping="Wrap"/>
</Grid>
<StackPanel Grid.Column="0" Grid.Row="0" HorizontalAlignment="Left" Name="ButtonPanel" VerticalAlignment="Top">
<Button Margin="0,10,0,10">Button 1</Button>
<Button Margin="0,10,0,10">Button 2</Button>
</StackPanel>
</StackPanel>
I have a WPF form that I am building. I want to specify a background image for the window, which is easy enough. However, I also want to specify a color so that the area of the form not covered by the image is white. I've seen some examples that show using two different background brushes, but when I try that VS.NET tells me I can't have multiple brushes.
This is the XAML I'm using
<Window x:Class="Consent.Client.Shell"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:cal="http://www.codeplex.com/CompositeWPF"
Title="Shell" WindowStyle="None" WindowState="Maximized" FontSize="24">
<Window.Background>
<ImageBrush AlignmentX="Left" AlignmentY="Top" Stretch="None" TileMode="None" ImageSource="logo_header2.png" />
</Window.Background>
<ItemsControl Background="White" VerticalAlignment="Center" cal:RegionManager.RegionName="MainRegion" >
</ItemsControl>
</Window>
This works great for the image, but the background not covered by the image is black. How do I make it white? Changing the image itself is not really an option.
Try this (I removed everything not directly relevant to the question to make the code clearer):
<Window x:Class="Consent.Client.Shell"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Background="White">
<Grid>
<Grid.Background>
<ImageBrush ImageSource="logo_header2.png" />
</Grid.Background>
<ItemsControl>
</ItemsControl>
</Grid>
</Window>
Basically, set the window's background to the behind the image color, than put a grid in the window and give the grid you background image, put everything inside the grid instead of directly in the window.
As an Extension to Nirs answer. If you want to have margins around your content, but let the background image be able to fill the whole window, you can also stack backgrounds using borders:
<Window x:Class="Consent.Client.Shell"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Background="White">
<Border Padding="10">
<Border.Background>
<ImageBrush ImageSource="logo_header2.png" />
</Border.Background>
<!--<Your content >-->
</Border>
</Window>
I'm not sure you can combine brushes. You could play around with ImageBrush, or you could forget the "background" and stack the items on top of each other in a Grid:
<Window x:Class="Consent.Client.Shell"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:cal="http://www.codeplex.com/CompositeWPF"
Title="Shell" WindowStyle="None" WindowState="Maximized" FontSize="24">
<Grid>
<Image Source="logo_header2.png" Stretch="None" VerticalAlignment="Top" />
<ItemsControl Background="White" VerticalAlignment="Center" cal:RegionManager.RegionName="MainRegion" >
</ItemsControl>
</Grid>
</Window>