Flexible XAML-only layout. Is it possible? - wpf

I want to create resizable window wich will initially autosize to its content.
If the size of the window reaches some limits autosizing is disabled and growing controls are either clipped or shown with scrollbars.
Autosizing also must be off when user resizes the window.
The real task is to create convinient resizable dialog window with text control.
When it contains not much and not few text lines it is reasonable to initially autosize the dialog. The amount of text increases and dialog becomes larger. Sure it must have some size constraints.
P.S. I think it's quite a frequent task to define the layout where the guiding role of the sizing during measure pass of the layout conditionaly swithces from children to parent and back.
Share you ideas or existing solutions. May be I'm missing something.
Thank you.
Update 1
Let me explain the algorithm:
1) Window is shown (let's imagine all data/content is already set).
2) Its size is adjusted as if window's properties were:
MaxHeight = ...
MaxWidth = ...
SizeToContent = "WidthAndHeight"
3) User tries to resize the window. And he can do it. Inner controls change accordingly their size.
This behavior is equivalent to the properties set:
MaxWidth= "{x:Ststic Double.PositiveInfinity}"
MaxHeight = "{x:Ststic Double.PositiveInfinity}"
SizeToContent = "Manual"
ResizeMode = "CanResizeWithGrip"

Yes, you can do it with XAML only using animations/triggers but it's a little tricky.
Just hook into TextBlock Loaded event(xaml only) and change SizeToContent=manual && MaxWidth&MaxHeight=PosInfinity inside EventTrigger using animation.

Many of WPF's panels automatically resize based on their children. I'd recommend looking through this article to get an idea of what kind of layout panels are available in WPF: WPF Layouts: A Visual Quick Start
But to answer your question, place all your controls you want automatically sized in a panel that automatically stretches its children, such as a Grid or a DockPanel, and set the MaxHeight and MaxWidth properties of the panel to prevent it from growing past a certain height/width.
<Grid MaxHeight="100" MaxWidth="200">
<!-- Place your content here -->
</Grid>
Depending on the default behavior of the parent control containing your panel, you may need to set the HorizontalAlignment and VerticalAlignment to something other than Stretch too.
<Grid>
<Grid MaxHeight="100" MaxWidth="200" HorizontalAlignment="Left" VerticalAlignment="Top">
<!-- Place your content here -->
</Grid>
</Grid>
If you want a ScrollBar instead of clipping the content, add a ScrollViewer inside the Grid

Related

WPF Control form resize

I have two controls on my form, i have two use case
When i drag from the right corner, i want to re size the form and all controls should be aligned appropriately
When i drag from the right edge, the right side controls should be hidden
I have already tried the Res size mode as can re size and i can handle the first user scenario.
I have used a View Box property which is enabling the re size of window when i drag and shrink it.
I am not able to find a control that can allow me to re size and hide a portion of the window at two different events
Some ideas for you.
You may handle the SizeChanged event for your window.
SizeChangedEventArgs has two propertis: HeightChanged, WidthChanged.
Maybe you can collapse the viewbox when only Widthchanged is ture.
Update:
After tested, Collapse viewbox will collapse the content in viewbox. So I write code like below to avoid this issue. But It's worked not very well. Just FYI:
<Grid>
<Viewbox>
<content/>
</Viewbox>
<content/>
</Grid>

How to create a UserControl with an irregular shape?

In my Silverlight 4 application I need to create a user control with an irregular shape. The "main display" of the UC is a standard rectangle but I need to have tabs (simple text blocks, where the user can click) that are outside of the main display rectangle.
Is this possible with Silverlight 4? If so, how?
Thanks in advance.
You can position elements of a control outside its normal layout in a number of ways. You could use Canvas but if most of the control is standard Grid rectangle then you can use a Grid. The trick is to use negative Margins.
<Grid x:Name="LayoutRoot">
<Border Margin="0 -22 0 0">
<TextBlock Text="I appear above the UserControl layout" />
</Border>
</Grid>
Note that if the Usercontrol is being used as the Visual root then this won't work because the Silverlight plugin will not render beyound its client rectangle.
It is, you can have transparent background behind the tabs which can let clicks through, effectively behaving as if the shape was different. The UserControl will still have a rectangular shape including the tabs, unless you wrap then into a Popup and float out of the UC with some offset.
Technically, you can have elements outside the UserControl's rectangle if you use a Canvas for your LayoutRoot instead of a Grid. Elements in a Canvas aren't clipped to the canvas size. I wouldn't recommend this, however, because you won't be able to use Margin to size and align your controls inside it. It would be better to have all child controls inside a Grid LayoutRoot.
Which brings us to the question of irregularity. If you want to 'see through' parts of the control and be able to click through them (i.e. click objects underneath it), all you need to do is keep the UserControl's and the LayoutRoot's Background to null or just not set it at all. Wherever there is a lack of any background, clicks will go through. Note that if you set the background to Transparent it will make the control behave as a rectangle (as if it's filled with solid color) with respect to mouse input.
Another thing is if you want to see HTML controls under the see-through parts of your app. Then, you'll have to use windowless mode, but that's another can of worms.

Auto resizing wpf elements with scroll bars (Rich text box, list box) vb

I'm having a problem where I have elements such as Listboxes and Rich Text boxes that I want to set to size automatically in xaml according to the size of the window, but I only want it to resize to the size of the window and then put scrollbars if the content is any bigger than that.
Unfortunately, the only way I can get scroll bars to work is if I set a specific height of the listbox/rich text box (which does not work because I want it to automatically resize to the height of the grid that it is contained within, which is generally the height of the window (auto).
Any help would be greatly appreciated.
You do not need to use fixed values for Width and Height - you should rather specify a minimum width/height for your controls using the MinWidth and MinHeight properties. Then try a layout similar to this:
<Window>
<ScrollViewer HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Auto">
<Grid>
<ListBox MinWidth="500" MinHeight="250"/>
<!-- any other controls... -->
</Grid>
</ScrollViewer>
</Window>
The Grid generally uses all the space it gets if its alignment properties are set to Stretch and if at least one row/column is set to be star-sized. In this case, there are only one row and one column, implicitly created, both star-sized by default.
To make the ScrollViewer work, you need to somehow set a minimum size of your content controls because otherwise the ScrollViewer does not know when to activate the ScrollBars. In the example above, I have done that using the MinHeight and MinWidth properties of the ListBox, but you could also set these properties on the Grid's RowDefinitions and/or ColumnDefinitions.
Now, if you resize the window, so that the Width becomes smaller than 500, you will see that scrollbars will appear. Just check it out.

How to calculate a bounding box for an Expander?

I have an Expander control and i need to calculate its bounds without invisible elements and margins. It commonly can be done by VisualTreeHelper.GetDescendantsBounds. But it seems that the rect is calculated by VisualTreeHelper doesn't depend on the expander state. For example:
http://i.piccy.info/i5/58/39/273958/collapsed.jpg
(i can't post images. sorry)
The same result as for expanded state (light green rectangle on the image). Does anybody know how to solve this problem?
The Expander control will set its content's visibility to Collapsed, which means it won't be considered during layout and won't be included in GetDescendantBounds. However, the Expander can be forced to have a larger size by the layout engine, and the Expander's own size is included in GetDescendantBounds.
Try setting VerticalAlignment="Top" on the Expander. The default is Stretch, which will allow it to increase in size if the parent has more space available. Also make sure you aren't explicitly setting the Height property.
This is the sample application. The style is applied here to the TreeView control and its items. But the problem doesn't depend on the style.

Stretching a WPF Canvas Horizontally

How do I make a Canvas stretch fully horizontally with variable width? This is the parent Canvas, so it has no parents, only children.
XAML Source: it displays in blend
http://resopollution.com/xaml.txt
Use a Grid as the top level element in your UI - it'll stretch to fill its container. Then put a Canvas with HorizontalAlignment="Stretch" inside the Grid and it'll behave the way you want.
<Grid xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Canvas Background="Blue"/>
</Grid>
That worked for me. The key is your top level UI element. While a Grid fills all available space by default, Canvases take up only as much room as their contents demand.
I'm guessing you've tried
canvas.HorizontalAlignment = HorizontalAlignment.Stretch
If this doesn't work, then what you could do is bind the Width and Height properties of the canvas to the ActualWidth and ActualHeight properties of the containing window.
You could use a dock panel to get it to fill the available width. The last item in a dock panel list of controls is automatically stretched to fill the remaining space.
<DockPanel>
<Canvas />
</DockPanel>
The canvas should do this automatically, unless you are manually setting the height and/or width. What kind of control are you trying to place the canvas on? Can you post your code?
The problem is that you're specifying the Height and Width. Without these properties, the control may appear to vanish in the designer, but it should size appropriately when you insert the canvas into another control.
If I recall correctly, the next version of WPF will have 'DesignWidth' and 'DesignHeight' properties that allow you to show the control in the designer with a given size without effecting it's measurement when inserted into other controls.

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