I am working at a WinRT application that implies some manipulations of an image at a WriteableBitmap level. On my page, I have ofcourse an image that shows the processing results. My objective now, is slightly different though, I would like to know if there is any way I could acces through code the built-in zoom in/out that could be achieved through pinch mode if on touch device on control + mouse wheel if on PC.
Here's a bit of my code where I've got the image :
<ScrollViewer VerticalScrollBarVisibility="Auto" HorizontalScrollBarVisibility="Auto">
<Image Grid.Row="0" x:Name="ImagePanel" Stretch="Uniform" VerticalAlignment="Center" HorizontalAlignment="Center"/>
</ScrollViewer>
I am asking this in case anyone might know if this can be achieved only because the zoom is very optimized and can be extremely useful :)
Thank you, any help or suggestions are greatly appreciated.
The ScrollViewer has a ZoomFactor property and a ZoomToFactor() method you can use.
Related
In my login UI, I have a footer image, which is showing perfectly in small devices. But on big screen devices (mainly on iPad) it is not showing fully.
I tried all Aspect property of Image, but not worked.
Screenshot:
I try a lot to fix this but didn't get a solution.
Attaching the LoginPage.xaml file with this question. Please suggest a solution for this issue. :)
Make sure (in the iOS project -> Assets) your image set has 3 different sizes xxx.png,xxx.png#2x and xxx.png#3x .
Which image will be used for your app? That depends on the device your app is viewed on. Higher resolution devices (larger and newer devices) have more pixels on their screens. Thus they need higher resolution images to display properly without any blurring.
If you don’t supply the higher resolution (#2x or #3x) images, your app will automatically try to scale the #1x image up. This is not good and can result in a distorted or blurry image!
Based on the file you linked in the comments, I think it would suffice to remove the bottom StackLayout wrapping the Image, and instead put Grid.Row="1" & VerticalOptions="End" to the bottom Image.
Please update your question with the relevant code to make the question and answers more helpful to others.
Remove latest StackLayout with image and add it after StackLayout with Grid.Row="1" like this
<Grid Grid.Row="1"
BackgroundColor="#c0eefb">
<Image
Source="ic_footer_image_xx.png"
Aspect="AspectFill"
HorizontalOptions="FillAndExpand"/>
</Grid>
Is it possible to put a image into a control in WinRT and then let the user zoom in and out etc?
Yes!
The easiest possible way is to put it inside a scrollviewer. You can zoom in and out whatever you like that way!
<ScrollViewer MaxZoomFactor="3"
MinZoomFactor="0.5"
ZoomMode="Enabled">
<Image Source="/Assets/logo.png" Width="200" Height="200"/>
</ScrollViewer>
In a WP7 game I'm building my Enemy classes are wrapped in an EnemyControl.
The Enemy Control uses a spritesheet of all the different animation states for that enemy type. There are only 4 images which I statically cache the bitmaps for.
The problem I have is that despite both the image being cached (BitmapImage statically and CacheMode="BitmapCache"), when the Image is loaded by the control it adds approximately 2 meg of Texture/System memory per control.
This is a significant problem as it limits the number of enemies I can conceivably have on screen.
Does anyone have any ideas how I could improve this situation? or otherwise solve it?
Here's the xaml if interested:
<Canvas x:Name="canEnemyControl">
<Canvas.RenderTransform>
<TranslateTransform x:Name="enemyControlTransform" X="0"/>
</Canvas.RenderTransform>
<Canvas.Clip>
<RectangleGeometry x:Name="clipGeometry" Rect="0,0,60,60" />
</Canvas.Clip>
<Image x:Name="imgEnemy" Stretch="None" CacheMode="BitmapCache" >
<Image.RenderTransform>
<TranslateTransform x:Name="enemyImageTransform" X="0" Y="0" />
</Image.RenderTransform>
</Image>
</Canvas>
I don't think your implementation will scale because I don't think the multiple Image elements know to share the same bitmap cache.
Solution: CompositionTarget.Rendering and WriteableBitmapEx
One possible solution would be to use CompositionTarget.Rendering for rendering like in my answer here. This fires an event before the screen is updated so you can do your own drawing. I believe this is how Krashlander and some other Silverlight games work (though I think he may have switched over to XNA in later versions).
Then I think that you can use WriteableBitmapEx to use one instance of your source image to draw it into multiple places on a buffer. You should scale much better because you have your buffer the size of your screen/viewport, and you have your one copy of each image. The memory requirements for displaying 1 enemy and 1000 should be the same.
I will add a disclaimer that I haven't tried this exact approach, but I do use CompositionTarget.Rendering in one of my apps for smooth screen updates.
I am loading an image on my page using
<Grid x:Name="LayoutRoot">
<Grid.Background>
<ImageBrush ImageSource="../Images/kisses.jpg" Stretch="Fill"/>
</Grid.Background>
...
This works great except for one thing. I'd like to use the same image as the splash screen and when the app is loaded and the splash screen goes away and the page background loads, I want the transition to be visually seamless. As it is, the image fills all 800 vertical pixels for when it's a splash screen and only (800 - ApplicationBarHeight) when it's a page background.
So I figured it was because I have it behind the LayoutGrid instead of behind the PhoneApplicationPage. But when I try to put it behind the PhoneApplicationPage (and make the LayoutGrid transparent) it doesn't work. Here's what I'm trying. Why doesn't this work?
<phone:PhoneApplicationPage.Background>
<ImageBrush ImageSource="../Images/kisses.jpg" Stretch="Fill"/>
</phone:PhoneApplicationPage.Background>
Thanks.
You should load the image in the LayoutRoot and set the opacity of the ApplicationBar to 99% - this way the image should be rendered with the full height / behind the AppBar.
Cannot test it myself at the moment, but if it doesn't work I will take a second look when I'm back in front of a PC :)
2 steps:
(1)
in <phone:PhoneApplicationPage
set shell:SystemTray.IsVisible = "False"
(2)
<Grid x:Name="LayoutRoot">
<Grid.Background>
<ImageBrush ImageSource="Assets/Images/Flowers.png"></ImageBrush>
</Grid.Background>
I am developing Windows phone 7 application, I need to do a slide show like application. I have the File[] when I swiping left or right the previous or next Image should show. how to Do it? I think it is possible through Manipulation events. but how to do this , I dont know Can u explain this?
The simplest way to create this effect woudl be something like this:
<ScrollViewer HorizontalScrollBarVisibility="Visible">
<StackPanel Orientation="Horizontal">
<Image Source="A.png" />
<Image Source="B.png" />
<Image Source="C.png" />
<Image Source="D.png" />
</StackPanel>
</ScrollViewer>
Although you could add the images through code.
If you want something more complex in your animation or need control over how an image can be interacted with you may want to do something different.
Before trying to use manipulations you may be able to use the Flick event from the toolkit which may make what you're trying to achieve easier.
It will all depend on what you're trying to do. Your question isn't explicitly clear.
See also how to get swipe in windows phone 7