WPF automatic resize font until it fits within parent control - wpf

I have a user control who's root element is a Grid.
I also have have a ContentControl that serves as a placeholder for some text that is filled when data is loaded. This control can be moved around within the user control and so it's position can be anywhere.
If the text is too long to fit within the root Grid of the user control, I want to reduce the font size of the ContentControl until the text fits.
My problem is that I can't seem to find an event that I can handle to do this process.
I tried using the ContentControl.LayoutUpdated event;however, the sender parameter for this always appears to be nothing...which is really not helpful!
I am really looking forward to any advise on how to achieve this.
Thank you
-Frinny

Wrapping your ContentControl in a Viewbox set to only scale down will do this for you:
<Viewbox StretchDirection="DownOnly" Stretch="Uniform">
<ContentControl Content="Some Text"/>
</Viewbox>

Related

AdornerDecorator - what does it matter where they are placed?

With some xaml like this:
<Grid Name="grid">
<AdornerDecorator>
<TextBox Height="23" HorizontalAlignment="Left" Name="textBox1" Width="120" />
</AdornerDecorator>
</Grid>
The WPF Snoop utility indicates textBox1 is a child of AdornerDecorator (as you would expect) but also that the AdornerLayer that AdornerDecorator creates is also a child. As a custom adorner added to the AdornerLayer can be displayed 'outside' the textbox, the AdornerLayer's drawing surface must stretch outside too (presumably all over the window).
So, what real significance does the placement of AdornerDecorator have (given we bind a UI element to the custom adorner, which we place in the AdornerLayer)? I know AdornerLayer.GetAdorner(textBox1) will get the first adorner layer in the visual tree up from textbox1, but what does it matter where that is (as the custom ardorner gets added to the layer and the custom ardoner knows which element it is bound to)?
The short answer is that it matters when you start to deal with controls that overlap other controls (in the z-index plane) and you care about whether or not a particular adorner layer shows on top of the overlapping controls. For example, when you use an ErrorTemplate, its contents get rendered in an adorner layer and if you don't supply an <AdornerDecorator> in your app (meaning that you just use the one provided by most Window templates), then you can end up with this happening.
By placing the <AdornerDecorator> where we want, we can control how this overlapping behaves.

How to do Silverlight overlay element

I am starting to learn SL...
I am trying to make a MediaElement of size X, and on the bottom of the movie frame some subtitles that will run.
I was unable to understand if I need absolute position or something else.
Please advice
thanks
If you need to us it as a subtitle you just need to put your TextBlock under the MediaElement on your Grid and need to give VerticalAllignment property as bottom on XAML. And it will be over it. Like this;
<Grid>
<MediaElement/>
<TextBlock VerticalAllignment="Bottom"/>
</Grid>
You may refer Grid Layout as relative positioning if you're new to silverlight. And can give a margin to your textblock or anything you want just take a look at the intellisense (if using VS) and you'll understand, if you're using expression blend it'll be a lot easier with UI.
If you want to use absolute positioning you'll need to use Canvas instead of Grid Layout, its the same and you can change anything to canvas with nearly no problem. In canvas, you need to use left and right properties instead of allignments. Like this;
<Canvas>
<MediaElement/>
<TextBlock Canvas.Left="0" Canvas.Top="400"/>
</Canvas>
Another option is stackpanel its not really suitable for LayoutRoot, but its pretty nice for controls. So if you want your subtitles to stay under your movie you should use StackPanel like this;
<StackPanel Orientation="Vertical">
<MediaElement/>
<TextBlock/>
</StackPanel>
So to sum up;
-If you want your subtitles to be on top of your movie use grid like the first example,
-If you have a fixed size and you want to place your subtitles anywhere you want use Canvas,
-And if you want to put your subtitles under your movie use StackPanel.
-My personal choice would be grid. =)
For more information you may check this article it seems like a nice one!
http://weblogs.asp.net/scottgu/pages/silverlight-tutorial-part-2-using-layout-management.aspx
Happy coding!!
The TextBlock will overlay (within a Grid layout) the MediaElement simply because it is declared after the MediaElement. VerticalAlignment="Bottom" will place it at the bottom of the Grid. You might want to set the Grid's width and height (instead of the MediaElement) that of the size of the video. The MediaElement will auto size to stretch the full size of the grid.
<Grid x:Name="LayoutRoot" Width="480" Height="320">
<MediaElement/>
<TextBlock TextWrapping="Wrap" VerticalAlignment="Bottom"/>
</Grid>

Window size and TabControl with DataBinding (Size of Items)

The following scenario bothers me:
I have a simple WPF Window that has a TabControl as content. The ItemsSource of the TabControl is bound to a list of objects. In order to visualize the objects I defined some DataTemplates. As the list of objects may have different types, the right visualization is chosen by the default template selector. This works fine and does not cause any trouble.
The issue that came up is the size of the window. The DataTemplates have different sizes. And I want the dialog to have a size that the largest DataTemplate fits. When I use SizeToContent in the Window, the Window changes its size everytime I change the tabs.
So, my questions is, how can I achieve to make the window fit the largest TabItem (which size is determined by the DataTemplate)?
thanks,
Florian
The problem you are having, is that because the larger DataTemplate is not shown, it's size is not taken into account when sizing to content.
Your options:
1) Manually set (min)width/height on appropriate controls (tabcontrol, Window, DataTemplate, etc)
2) If you know that a certain tab is always going to be bigger than the rest, you can bind the width/height of the other tabs to the bigger tab:
<TabItem>
<StackPanel Name="stackPanelBiggest" />
</TabItem>
<TabItem>
<StackPanel Width="{Binding ElementName=stackPanelBiggest, Path=ActualWidth}" />
</TabItem>
I think that for the above to work, the biggest tab has to be first one shown. Although the tab control destroys the visual tree of the previous tab when swithching to another tab, this method is still working for me (despite the fact that the ActualWidth should be 0 or NaN, after switching tabs).

Changing FontSize relationally to the windowsize with WPF?

Is it possible, that the FontSize getting smaller if I shrink the window and getting bigger if I enlarge the window?
Wrap your text inside a Viewbox.
<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation">
<Viewbox>
<TextBlock Text="Sizes to fit!"/>
</Viewbox>
</Window>
I've never tried this, but I imagine you can bind the font size property of your text to the window size through a converter method. I wouldn't try to bind directly, as that way madness lies.
The other option would be to handle the window resize events and send the font size to each control manually...
--edit--
Just searched Google and found this result, which may be what you want.

How to relative scale size of User Control?

How to relative scale size of User Control like image (in image editor).
Example (100%):
(source: stegnar.com)
Scaled down UC (70%):
(source: stegnar.com)
Well I achieve this in picture editor, but I would like in WPF. :) I need this to adjust my application to different screen resolution, while nothing hiding (no scrollbars).
You could try the ViewBox control that scales up/down its content so that it fills the available space.
<Window x:Class="WpfApplication1.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:WpfApplication1"
Title="Window1">
<Grid>
<Viewbox StretchDirection="Both" Stretch="Uniform">
<local:UserControl1 Height="600" Width="600"/>
</Viewbox>
</Grid>
you can place the whole container into a ViewBox
<Viewbox StretchDirection="Both" Stretch="Uniform">
<Grid>...</Grid>
</Viewbox>
you don't have to place each single textblock in it!
Use of Viewbox (as said by Milan Nankov) is a great idea. One thing that I must warn you is that it also zooms in or out other visual aspects as well.
For example, a Textbox with dimension 200 X 1000 is very different from a Textbox with dimension 20 X 100 zoomed in 10x.
WPF provides many layouting options which can change dimension of the controls according to the size of the container. But it doesn't change the size of the text. Viewbox overcomes this issue, but it introduces another issue. Check the image below which shows the same textbox in a viewbox before and after zooming.
One trick which could be used is to place every textblock in a viewbox. But I guess that would be an overkill, and I seriously don't having any backing for this trick. Please do check for yourself and reply whether it's practical or not.
Another trick could be to bind the control's height to the font size. We would be needing a converter in that case. Please refer to this reply.. Resize font in TextBox in Grid

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