Showing Canvas Outside UserControl boundary - silverlight

I've found several threads on various sites vaguely related this, but no solid answers.
Here's a simplified example: I want to create a usercontrol that has a textbox and a small icon beside it. If you click the image, I want to have a canvas appear under the control that has information in it. The canvas would be outside the usercontrol's boundary.
I have gotten this "sorta" working. If I put the textbox, graphic, and just a canvas on the control, with the canvas outside the clip of the usercontrol - I can make the canvas visible/invisible as desired.
When I add stackpanels and such, it starts exhibiting odd behavior - sometime simply vanishing.
So, here's the question - what is the right way to do this? Or, is there a "right way"?

what you need to do is put your canvas into a <Popup> control. then, show the popup when needed. Here is a video showing how to use a <Popup> control, Here is the MSDN documentation.

Related

WPF Canvas and DrawingVisuals disappear

I have a set of User Controls, derived from FrameworkElement. Each host one or more DrawingVisuals. These drawing visuals can represent text, graphics, progress meters etc and are used to display the states of various HMI devices.
These, appearance-wise work fine in a grid - images are rendered, text and backgrounds appear fine, dependency properties can be set. However, when I encapsulate them in a Canvas, they disappear all but for the drawing visuals representing labels. And even for these, only the text rendered by DrawingContext.DrawText is visible. Operations performed by dc.DrawImage, cd.DrawRectangle etc do not appear.
Can someone please shed some light on why this might be.
Thanks
Are you positioning your controls properly? In a grid you have margins for each item, where as in a canvas you have to set Canvas.Top and Canvas.Left for each element. Is it not that those items are hidden underneath something? Try using snoop to use if the controls are actually part of Canvas children or if they have not been added at all.
You can read more about Canvas on MSDN

Image glimmer or sparkle animation

I've been searching for awhile, but haven't been able to find anything. I'd like to be able to add kind of a glimmer or sparkly animation on an image element in wpf.
Essentially the effect here I'm after here is the same that you get with trading cards that are "foil's".
I'd like to have an image, and then be able to add this animation to it at will. I'm thinking maybe some kind of user control, or template possibly. Hopefully generic enough that I can just toss an image at it and it will just overlay the image and run.
Any ideas?
A simple construction that easily can be turned into a control is by nesting the image in a Grid and adding a second Grid (on top) as a sibling.
De second grid can be given a linear gradient brush that is primarily transparent but does contain a white glimmer.
This brush can be animated; you could move it and change the opacity of the grid/brush.
This way you do not change the image.

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.

WPF Tiled Background Misalignment

We have quite a complex WPF application (that I cannot show here) that somehow has the tiled background misaligned of one of its user controls. I was unable to reproduce this problem in a "clean" WPF project but will try to illustrate the problem in this picture:
(source: kintespace.com)
The gray area represents the user control and the black and red checks represents the tiled background inside the user control. The white background represents the window hosting the control. The VisualBrush is used here but the same problem comes with the DrawingBrush. I would prefer not to use the ImageBrush.
Can you open a "clean" WPF project and build something that will cause a tiled background to be misaligned like this?
You can do this if the layout root of the user control has a -10 left margin and a -10 top margin. the tiled backgoround in on the layout root of the usercontrol so, it looks like a alignment problem not a brush problem.
This problem is related to the tiled background cramming itself into the calculated height of the UserControl instance in the hosting Window. I am still unable to replicate this problem in a new project but it is "solved" (by stacking panels in the user control horizontally instead of vertically).
Here are two diagnostic techniques that can be useful in situations like yours:
Take your complex project, make a copy, and start tearing out large sections of code and XAML until the problem disappears. Then put the last section back and tear things out more gently. Repeat until you find the change that makes the difference.
Run the application, break where a local variable references your UserControl, then explore the visual tree just above and below your UserControl in the Locals or Watch window. Look at each Visual's internal properties VisualOffset, VisualTransform, and VisualContentBounds. These properties will usually clue you in to what property is being set incorrectly, and from there you can figure out why.

How can I animate a transition when moving a child from one panel to another in Silverlight

I would like to animate a transition when moving content between two panels. I am getting a bit map image of a detail record and docking it as a thumbnail in the panel below. The docking area is in a footer grid and the content detail is in another grid that sits above the dock area (the dock and the main content area live in separate rows of the root layout control - another grid).
I have tried implementing this with a ScaleTransform and a TranslateTransform, simultaneously shrinking the image and moving it towards the footer control. When it moves into the footer control, it gets clipped even though the image Canvas.ZIndex property is set to a very high number. Eventually the thumnbail will need to be a child of a StackPanel that sits inside the footer grid.
Thanks for your consideration and help.
I had a similar problem (clipping) with a WPF animation I had. The problem was that the owner of the animation needed to be a parent of both containers for the animation to work (in my case I made it the actual window holding the containers).
Without any code, I can't see if that is your problem, but I thought I would throw it out there.
You can see my code where I animate moving from one container to another here:
http://wiassistant.codeplex.com/sourcecontrol/changeset/view/36638?projectName=WIAssistant#924851
(See the AnimatePaneBox method at the bottom of the file.) This may or may not be useful to you.
I've done something similar by creating a Canvas that sits over the top of both containers, using a WritableBitmap (if necessary) to create a rendering of the object that you're moving and attach it to that Canvas, animate the bitmap (translate, scale, opacity, whatever), and then pop the new object in under it at the end of the animation. It can be brittle if your controls need to be able to move or resize, but in most of my circumstances it's been a reliable hack.

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