Zooming on a particular image inside a stackpanel consits of ten images - wpf

I have a scrollviewer with horizontal stackpanel having 10 images as children. I need to perform zooming on a particular image which is in view when start the pinch gesture. Is it possible to achieve that. I tried to get the image in a separate layout when start the pinch but it makes the user to start the pinch twice.So kindly help me to get that

Do a click event on the image, then popup a window with a semi transparent background and an image control. Then apply pinch events to zoom and mouse move events to pan.
something like this article:
http://codecopy.wordpress.com/2011/12/15/wp7-pinch-and-pan-zoom-an-image/

Related

How do i create xaml (silverlight) animation like attacted image?

I want to create animation like this image, i'm wondering how do i get start for this ? in silverlight xaml
this bar will increased or decreased in animation
thanks for any help
I would create image overlay to create grid effect and would draw solid rectangles under the image. Animate rectangles using standard XAML animations.
Or even better: animate black overlay rectangles covering top of bars.
Sent from windows phone.

How can you use an ImageBrush to display a specified area of an image as the background of a rectangle?

I'm trying to add a zoom feature for an image viewer control I'm creating. When viewing the image, holding down the left mouse button brings up a rounded rectangle that is zoomed into the image. I figure I can use An ImageBrush as the background but I can't figure out how to make it just display a specified area of the image. Can this even be done?
By using the Viewbox.

How to draw onto a PictureBox image when control resizes?

I am using the pictureBox_Paint event to try and draw an overlay onto the image in a PictureBox.
This is working fine until I resize the PictureBox (set to use SizeMode.Zoom), when I do this the overlay graphic is drawn off position by the margin between the image and the edge of the PictureBox. I guess I need to use the ImageRectangle somehow but this is not public.
I would create a custom usercontrol instead, you would have much more control, and would not be difficult to build.

WPF Scale Transform and ScrollViewer - When Zoomed can't scroll beyond original size

I have a StackPanel inside of a ScrollViewer.
I have a slider that does a scale transform on the stackpanel to allow zoom-in and zoom-out functionality. The problem is that when I zoom in, the scrollviewer doesn't treat the content as being 'bigger'.
So, if I scroll in a little and scroll as far right as I can go - it stops me before I get to the end of the content. If I zoom back out to the untransformed level, I see that it's stopping exactly at that point. If I zoom in a lot, I can only see a small fraction of my total content when I scroll all the way over.
I can change the TransformOrigin to control which side loses the most content; but I figure there should be some way for the scrollviewer (or another control?) to take care of it for me.
Are you doing render transform, or layout transform? You should be doing the latter.

WPF and Silverlight controls and layouts pan and zoom capabilities

I would like to understand the general requirements for WPF/Silverlight layout for making it possible to implement pan&zoom (drag and zoom) features. I don't mean pan&zoom for an image but for a total page (window) layout (or part of it) with some controls.
What features of the layout and what features of used custom controls make layout fixed and pan&zoom impossible?
General rule
With few exceptions, everything in WPF can be panned, zoomed, rotated, stretched, etc to your heart's content. This include single controls like Button, compound controls like ListBox, and containers like StackPanel.
The exceptions
Here are the exceptions:
If you are using Adorner and your AdornerDecorator is outside the panned/zoomed area, then the Adorners attached to your panned/zoomed area will pan but not zoom. The solution is to put an additional AdornerDecorator inside the panned/zoomed area.
If you use a Popup, it will display at the panned/zoomed location of its PlacementTarget but it will not itself be scaled. It will also not move as you pan the area containing its PlacementTarget (basically it sits in its own surface above the target control). To get around this, use a zero-size Canvas with high Z order instead when you want something to pop up within the zoom/pan area.
Any ContextMenu you define will be shown inside a popup, so the menu items will display normal size even when the area you clicked on is zoomed in or out. Because of the nature of a context menu, this is probably desirable behavior. If not, you can wrap the menu items in a ViewBox and tie the zoom to your main area's zoom.
Your ToolTips will display normal size even if the UI is panned or zoomed. Same solution as for ContextMenu.
If you used WinForms integration to integrated legacy WinForms controls and UI, they will not properly pan, zoom and clip in certain situations. There is an advanced technique for working around this, where you implement the WinForms control off-screen, then using BitBlt or similar copy the image into your window as an image, and forward mouse clicks and keystrokes to the offscreen window. This is a lot of work, though.
If you bypass WPF and directly use GDI+ or DirectX, or use Win32 hWnds to display content or UI, that content or UI will not be properly panned, zoomed or clipped to the window unless you do it yourself in your interface code.
Final notes
A good WPF UI always uses panels like Grid, DockPanel, etc to lay out controls in a flexible manner so they automatically adjust to container sizes, rather than using fixed sizes and positions. This is also true for the internal contents of your pan/zoom area as well, BUT there is an exception to this rule: the outermost element in your pan/zoom area must have a specified size. Otherwise what will define the area being panned/zoomed over?
The easy way to implement pan/zoom capabilities is to adjust the RenderTransform of the outermost control in your pan/zoom area. There are many different ways to implement controls for panning and zooming, for example you could use toolbar buttons and sliders, scroll bars, mouse wheel, spacebar+drag to pan, draggable areas of panned UI itself, or any combination of these. Whichever interface you choose, just have it update the RenderTransform appropriately from the code-behind and you're good to go.
If your chosen panning mechanism is scroll bars, you might want to use a ScrollViewer and only use the RenderTransform for the zoom.
Be sure you set clipping on the pan/zoom area. Otherwise if you zoom in or pan items off the side, they will still be visible outside the pan/zoom area.
Use a MultiScaleImage or Canvas area, and place everything you need to pan and zoom in it
<Canvas x:Name="panZoomPanel" Background="Transparent">
</Canvas>
In code use make a TranslateTransform and a ScaleTransform in a TransformGroup to pan and zoom
Check out other SO post or this example or this one
In general you can treat any composite set of UI elements the same as you would treat a single UIElement so the case of an image isn't really different than doing the same for an entire application. The best way to handle zooming based on user input (as opposed to automatic scaling that Viewbox does) is applying a ScaleTransform. This can be set on a high level parent element, like a Grid at the root of a Window layout. For panning you can combine in a TranslateTransform or in some cases use a ScrollViewer to handle moving the view of the content.
One really easy way of implementing zoom in XAML is to use a Silverlight ViewBox. This zooms the XAML not the pixels. You can specify the stretch to use and the ViewBox will scale based on this (Fill, None, Uniform etc). There are some great Viewbox blog posts on the web if you search for Silverlight+Viewbox on Google.
The panning is easily accomplished with a similar mechanism to drag and drop and there are also numerous how-to blog posts on this, available via Google. Just amounts to capturing MouseDown, MouseMove and MouseUp events.

Resources