WPF: How to set background of TabItem? - wpf

How to set the background of TabItem? I tried the following code:
<TabControl>
<TabItem Header="Test" Background="Blue" Foreground="Red" />
</TabControl>
Foreground works, but Background does not work.
Any ideas? Thanks

What is happening is that in the case of a single tab, it is always selected, and so you are only seeing the selection style of the tab item.
For example, take a look at the following TabControl:
<TabControl>
<TabItem Header="Tab A" Background="Blue" Foreground="Red">
<Grid />
</TabItem>
<TabItem Header="Tab B" Background="Green" Foreground="Navy" >
<Grid />
</TabItem>
<TabItem Header="Tab C" Background="LightBlue">
<Grid />
</TabItem>
</TabControl>
Tab A will not display its Blue background until you select a different tab. If you truly want the Background to remain the same regardless of whether it is selected or not, you will need to override the control template of the TabItem.
See the question TabItem Background color changes when tabitem selected or hover over for an example of how to do this.

Related

MahApps.Metro AnimatedSingleRowTabControl doesn't work

For some reason my Tab Control doesn't seem to work as described.
Instead of seeing this (From Mahapps site)
I see this
I have tried fiddling with every single property to try to get the scroll bar to go away and to have left/right scroll buttons as shown in the example, but absolutely nothing works.
What am I missing?
EDIT: - Added my XAML
<Controls:MetroAnimatedSingleRowTabControl Controls:TabControlHelper.IsUnderlined="True" Margin="5" ScrollViewer.PanningMode="Both" ScrollViewer.CanContentScroll="False" ScrollViewer.HorizontalScrollBarVisibility="Hidden">
<Controls:MetroTabItem Header="Thread Image Download">
</Controls:MetroTabItem>
<Controls:MetroTabItem Header="Random Board Stats">
</Controls:MetroTabItem>
</Controls:MetroAnimatedSingleRowTabControl>
It doesn't exist a style key for this TabControl. So you must add the resource dictionary to the place where you need it. So MahApps should solve this in the next releases (site note for me).
<Grid>
<Grid.Resources>
<ResourceDictionary Source="pack://application:,,,/MahApps.Metro;component/Styles/Controls.AnimatedSingleRowTabControl.xaml" />
</Grid.Resources>
<TabControl>
<TabItem Header="this tabcontrols tabs">
<TextBlock FontSize="30" Text="Content" />
</TabItem>
<TabItem Header="appear only on a single line">
<TextBlock FontSize="30" Text="Content" />
</TabItem>
<TabItem Header="if they are overflowing">
<TextBlock FontSize="30" Text="Content" />
</TabItem>
<TabItem Header="instead of wrapping them">
<TextBlock FontSize="30" Text="Content" />
</TabItem>
</TabControl>
</Grid>
Hope this helps.

WPF Tabcontrol not showing TabItem content until selection changes

I have the following Tabcontrol definition:
<TabControl Grid.Row="0" SelectedItem="{Binding SelectedTab}" >
<TabItem Header="Foo" IsSelected="True" >
One
</TabItem>
<TabItem Header="Bar">
Two
</TabItem>
<TabItem Header="Smeh">
Three
</TabItem>
</TabControl>
I would expect the "Foo" tab to be selected and the 'One' text to be visible. This is not the behaviour I'm seeing. It appears all tabs are unselected and until I click on a different tab (clicking on the one that is supposedly already selected does nothing), then the tab looks selected and shows content.
Does anyone know why the TabControl works like this and how to fix it to work correctly?
By default there is no selected item in the TabControl. If you want to synchronize some model with the selected item, try
<TabControl Grid.Row="0" SelectedItem="{Binding SelectedTab, Mode=OneWayToSource}" >

TabControl: all TabItems collapsed, but content of 1st TabItem still visible

I've got a rather strange behavior on a TabControl, whose TabItems are all collapsed: The content of the first TabItem is still visible (but the header is not).
The TabControl and its TabItems are setup like this:
<TabControl>
<TabItem Header="Data 1"
Visibility="{Binding Path=DataTable1.HasRows,
Converter={StaticResource BoolToVisibility}}">
<UI:ShowData DataContext="{Binding Path=DataTable1}"/>
</TabItem>
<TabItem Header="Data 2"
Visibility="{Binding Path=DataTable2.HasRows,
Converter={StaticResource BoolToVisibility}}">
<UI:ShowData DataContext="{Binding Path=DataTable2}"/>
</TabItem>
</TabControl>
If none of the data tables contains any rows, none of the TabItems should be shown. (I known that I could hide the whole TabControl in that case, but that's not the point here.)
Actually the content of the tab item "Header 1" will be displayed despite the TabItem being collapsed! The TabItem's header itself is collapsed, the TabItems border which contains its content and the content itself are displayed.
Edit/Add:
This can easily be reproduced using this code (note using Collapsed or Hidden does not make any difference:
<TabControl>
<TabItem Header="Test 1" Visibility="Hidden">
<Label>Test1</Label>
</TabItem>
<TabItem Header="Test 2" Visibility="Hidden">
<Label>Test2</Label>
</TabItem>
</TabControl>
So what's wrong here? Any help/hints are appreciated!
Ok, so you've found a real problem here... I looked around online and found several posts that relate to this. Some say that this is a bug, while others say that it is the designed behaviour. don't know which, although it certainly seems to be more of a bug than a feature.
Either way, you want to know how to deal with the problem. .. there are several solutions. One is just to set the TabItem.Content to null whenever you want to hide the tab and another is another involves adding an empty TabItem and selecting that item before hiding (so that it's empty content is shown).
You can attach a handler to the TabItem.IsVisibleChanged Event to be notified when the Visibility property has been changed:
public void TabItemIsVisibleChanged(object sender, DependencyPropertyChangedEventArgs e)
{
// Hide TabItem.Content here
}
Here are some links to the relevant posts:
Bug in TabControl/TabItem`s content visibility?
WPF TabControl - Select different tab when TabItem Visibility changes
Is there a workaround for this tabcontrol/tabitem bug
Another solution that I prefer over the ones suggested: Bind the visibility of the TabItem and its content to the same property (using the BooleanToVisibilityConverter).
Here's a simple example:
<UserControl.Resources >
<BooleanToVisibilityConverter x:Key="boolToVis"/>
</UserControl.Resources>
<Grid>
<TabControl>
<TabItem Header="TabItem 1" Visibility="{Binding Item1Visibility, Converter={StaticResource boolToVis}}">
<Label Content="Content 1" Visibility="{Binding Item1Visibility, Converter={StaticResource boolToVis}}"/>
</TabItem>
<TabItem Header="TabItem 2" Visibility="{Binding Item1Visibility, Converter={StaticResource boolToVis}}">
<Label Content="Content 2" Visibility="{Binding Item1Visibility, Converter={StaticResource boolToVis}}"/>
</TabItem>
</TabControl>
</Grid>
Could be a WPF bug, anyway bypass by binding the content visibility to the tab item visibility.
<TabControl>
<TabItem x:Name="_test1Tab" Header="Test 1" Visibility="Hidden">
<Label Visibility="{Binding ElementName=_test1Tab, Path=Visibility}">Test1</Label>
</TabItem>
<TabItem x:Name="_test2Tab" Header="Test 2" Visibility="Hidden">
<Label Visibility="{Binding ElementName=_test1Tab, Path=Visibility}">Test2</Label>
</TabItem>
</TabControl>
My solution to this was to put the TabItem I wanted to hide in another position. The problem happens only if you want to collapse only the first TabItem.

XAML - The property 'Content' is set more than once

Very new to WPF and XAML. I can't get my head around why I can't place a WPF control where I would like in the following code. My issue is where the <canvas></canvas> tags are. Anything I put in this place gives me 'The property 'Content' is set more than once'
If anyone could explain in simple terms where the Content property is set that would be most helpful.
I have checked out the following articles to no avail:
the property 'Content' is set more than once
the property content is set more than once
Property content is set more than once
The property 'Content' is set more than once Button WPF
ControlTemplate causeing error "The property 'content' is set more than once"
<Window x:Class="PDFIndexer.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">
<Grid x:Name="ParentGrid">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="1*" />
<RowDefinition Height="25" />
</Grid.RowDefinitions>
<Menu Grid.Row="0" >
<MenuItem Header="File" >
<MenuItem Header="Open Project" Click="MenuItem_Click_1"></MenuItem>
<MenuItem Header="Save Project"></MenuItem>
<MenuItem Header="Close Project"></MenuItem>
<Separator></Separator>
<MenuItem Header="Exit"></MenuItem>
</MenuItem>
<MenuItem Header="Edit"></MenuItem>
</Menu>
<TabControl Grid.Row="1">
<TabItem Header="Document Flow" >
This is where the outline of the entire document will be placed.
<Canvas></Canvas>
</TabItem>
<TabItem Header="Preview">
This is where the preview will be drawn to screen.
</TabItem>
<TabItem Header="Resources">
This is where the resources { graphic files, fonts, data files }
</TabItem>
<TabItem Header="Code Library">
This is where the user can save re-usable bits of code. Useful when adding intel barcodes or Address blocks etc...
</TabItem>
</TabControl>
<StatusBar Grid.Row="2">
Items
</StatusBar>
</Grid>
By adding your text description to your TabItem you added Content then when you added the Canvas you added an additional item of Content which is not allowed for the TabItem. You need to use a Control that can hold a collection of Children such as Canvas, Grid, StackPanel etc. Try something like this.
<TabControl Grid.Row="1">
<TabItem Header="Document Flow">
<Canvas>
<TextBlock>
This is where the outline of the entire document will be placed.
</TextBlock>
</Canvas>
</TabItem>
<TabItem Header="Preview">
This is where the preview will be drawn to screen.
</TabItem>
<TabItem Header="Resources">
This is where the resources { graphic files, fonts, data files }
</TabItem>
<TabItem Header="Code Library">
This is where the user can save re-usable bits of code. Useful when adding intel barcodes or Address blocks etc...
</TabItem>
</TabControl>
Certain containers only allow 1 element, other containers allow >1 element.
When you get the error message 'Content' is set more than once, it means you have tried to put more than one type of element in a container that only allows 1 element.
Maybe try this (not tested):
<TabItem Header="Document Flow" >
<StackPanel>
<TextBlock>This is where the outline of the entire document will be placed. </TextBlock>
<Canvas></Canvas>
</StackPanel>
</TabItem>
Try to wrap a content of TabItem in a Grid and use TextBlock to show text:
<TabItem Header="Document Flow" >
<Grid>
<TextBlock Text="This is where the outline of the entire document will be placed."/>
<Canvas></Canvas>
</Grid>
</TabItem>

TextBlock color animation in TabControl

I am currently working in wpf. I was animating the color of textblock control inside the tab item. When the tab is selected, i want to change the foreground to white, i-e
<ColorAnimation
Storyboard.TargetName="buttonText"
Storyboard.TargetProperty="(TextBlock.Foreground).(SolidColorBrush.Color)"
To="White" Duration="0:0:.1" />
the tab control code is;
<TabControl Name="tabSteps" Template="{StaticResource OfficeTabControl}">
<TabItem Header="Info" IsSelected="True">
<TextBlock>Info content</TextBlock>
</TabItem>
<TabItem Header="Recent">
<TextBlock>Recent content tab</TextBlock>
</TabItem>
<TabItem Header="New">
<TextBlock>New content tab</TextBlock>
</TabItem>
<TabItem Header="Print">
<TextBlock>Print content tab</TextBlock>
</TabItem>
<TabItem Header="Save & Send">
<TextBlock>Save & send content tab</TextBlock>
</TabItem>
<TabItem Header="Help">
<TextBlock>Help tab</TextBlock>
</TabItem>
</TabControl>
I want to target the textblock.
But it isn't working.
Any help will be appreciated.
I am following this work
http://www.codeproject.com/Articles/155211/Building-a-control-template-style-for-the-tabContr.aspx
Using the VisualStateManager, create a state for when your TabItem is selected. You can then specify the animation you mentioned to start as a transition to and from the selected state (see http://blogs.intuidev.com/post/2010/01/26/TabControlStyling_PartTwo.aspx for a tutorial).
The default style for the TabControl is here (http://msdn.microsoft.com/en-us/library/cc645035(v=vs.95).aspx), or you can easily generate it if you use Expression Blend.
You could also use this approach (a programmatic trigger) : https://stackoverflow.com/a/4958562/914602

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