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Reordering ListView items in UWP messes up the content

I'm using ListViews to make a kanban list in UWP. As the picture below shows, re-ordering items a few times results in the content of one or some of them being wrong.
Further re-ordering will have the content going back and forth being correct and wrong and everything is back to normal when re-loading the page which means there's not data change but just the image control displaying the wrong image. ( It can happen with any other control too )
For reference, The images are local files which I'm loading in the Image control's Loaded event, and the ListView simply has CanReorderItems and AllowDrop set to true.
Here's how the XAML looks
<ListView x:Name="LView" MinWidth="240" Grid.Row="1" ItemsSource="{x:Bind List.Tasks}" ReorderMode="Enabled" CanReorderItems="True" AllowDrop="True" CanDragItems="True" SelectionMode="None" IsItemClickEnabled="True" ScrollViewer.VerticalScrollBarVisibility="Hidden" ScrollViewer.VerticalScrollMode="Enabled" ScrollViewer.IsVerticalRailEnabled="True" ItemClick="LView_ItemClick">
<ListView.ItemContainerStyle>
...
</ListView.ItemContainerStyle>
<ListView.ItemTemplate>
<DataTemplate x:DataType="mongo:Task">
<Grid Padding="12 0" >
<Grid.RowDefinitions>
...
</Grid.RowDefinitions>
<Border CornerRadius="4 4 0 0" Margin="-12 0" >
<Image x:Name="Cover" MaxHeight="160" Stretch="UniformToFill" Tag="{x:Bind Attachments}" Loaded="Image_Loaded" HorizontalAlignment="Center" VerticalAlignment="Bottom"/>
</Border>
...
And here's the Loaded event
private async void Image_Loaded(object sender, RoutedEventArgs e)
{
var img = sender as Image;
if (img.Source is object) return;
var attachments = img.Tag as ObservableCollection<TaskAttachment>;
if (attachments is null) return;
var cover = attachments.Where(_a => _a.is_cover).FirstOrDefault();
if (cover is object && cover.type == "image")
{
var path = BrandboxSettings.Instance.server_path + "projects\\" + cover.path;
Output.WriteLine(path);
var file = await StorageFile.GetFileFromPathAsync(path);
using (IRandomAccessStream fileStream = await file.OpenAsync(Windows.Storage.FileAccessMode.Read))
{
// Set the image source to the selected bitmap
BitmapImage bitmapImage = new BitmapImage();
await bitmapImage.SetSourceAsync(fileStream);
img.Source = bitmapImage;
}
}
}
Edit: It's worth noting that even if one of the cards does not initially have an image, reordering will cause it to have one.
Any help would be appreciated

Okay so I tried changing the ItemsPanel to a StackPanel and it seems to be working now.
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<VirtualizationStackPanel/>
</ItemsPanelTemplate>
</ListView.ItemsPanel>
Edit:
It also seems to work by setting the Panel to VirtualizationStackPanel

How set the property of WPF DataGrid (mvvm) in "MouseDown" event based on "sender"?

I'm having some trouble to set one property (MouseDown event) value based on it's sender. I have "MyPhotoA" and "MyPhotoB" binded to an observableCollection. Both trigger the same event "MyOnClick" Here is the xaml:
... stuff
<DataTemplate>
<Image Source="{Binding MyPhotoA, UpdateSourceTrigger=LostFocus}" MouseDown="MyOnClick" />
</DataTemplate>
... stuff
<DataTemplate>
<Image Source="{Binding MyPhotoB, UpdateSourceTrigger=LostFocus}" MouseDown="MyOnClick" />
</DataTemplate>
... stuff
These two datatemplates are used for two datagridtemplatecolumns in the datagrid. Hence there are two columns of images and the user clicks one. I want to set the source on the image clicked.
The event "MyOnClick" is something like this:
private void MyOnClick(object sender, MouseButtonEventArgs e)
{
var myImage File.ReadAllBytes("c:\\MyImage.jpeg")
var dc = (sender as System.Windows.Controls.Image).DataContext;
MyModelClass itemSelected = (MyModelClass)dc;
itemSelected.PhotoA = myImage;//Setting PhotoA
itemSelected.PhotoB = myImage;//Setting PhotoB
//How to set the photo based on "sender" property? Like:
//sender.[somestuff]=myImage;
}
I'd like to use the same method to set data in PhotoA and PhotoB based on the sender property binded to it. So if user click in the "PhotoA" DataGrid cell, the image is setted to "PhotoA". If click is done in "PhotoB" then "PhotoB" data is setted.
!!!Note!!!: I don't want tricks like
If (sender.name="PhotoA") then
itemSelected.PhotoA = myImage;
else
itemSelected.PhotoB = myImage;
Thanks in advance
[Workaround Update]
I could not find the answer so I used a workaround:
1)edit xaml code, adding a property "name" to each Photo:
<DataGridTemplateColumn>
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<Image Name="ImageMyPhotoA" Source="{Binding Photo}" MouseDown="MyOnClick" />
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
On the event, I manually added the bin to the the observable collection.
private void MyOnClick(object sender, MouseButtonEventArgs e)
{
var myImage = File.ReadAllBytes("c:\\MyImage.jpeg");
var dc = (sender as Image).DataContext;
MyModelClass itemSelected = (MyModelClass)dc;
var senderName = (sender as Image).Name;
if (senderName == "ImagePhotoA")
{
itemSelected.PhotoA = myImage;
}
if (senderName == "ImagePhotoB")
{
itemSelected.PhotoB = myImage;
}
}
Conclusion
Setting properties in "MouseDown" event based on Sender (Sender.[SomeSenderProperty] = "Something") seems not possible OR over complicated. I suggest to mark the sender's name in xaml (like the example). Thanks for the good fellows for your help, I really appreciate.

You're essentially trying to set the source property of an image the user clicked.
When you do that you want it to persist, presumably, and you probably won't want to overwrite the binding so make your binding twoway.
<Image Source="{Binding MyPhotoA, Mode=TwoWay}"
In your click handler.
Cast your sender to image.
var img = sender as Image;
(You should routinely null check when you do as anything.)
But this gives you a reference to the appropriate image control to work with.
Set the value.
As Clemens points out, I was overcomplicating this with:
img.SetCurrentValue(SourceProperty, Abitmapimage);
And you can just do:
img.Source = new BitmapImage(new Uri(#"C:\MyImage.jpeg"));

Call GIF image source from the code behind in WPF c# for the tabcontrol's setter

i am using wpf tab control and setting the Icon and text in the tab header through style, i am able to set the text dynamically through getter and setter but can not able to set the image source. I tried to bind the image source through getter and setter but failed. Following is the style code in which i want to set the image source dynamically from the code behind.
-->
<Setter Property="HeaderTemplate" >
<Setter.Value>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<!--<Image gif:ImageBehavior.AnimatedSource="{DynamicResource MyFillBrush}" Width="20" />-->
<Image gif:ImageBehavior.AnimatedSource="25.gif" Width="20" />
<Label Content="{Binding }"/>
</StackPanel>
</DataTemplate>
</Setter.Value>
</Setter>

I know this is a bit old thread, but this is how you update the AnimatedSource from code:
var image = new BitmapImage();
image.BeginInit();
image.UriSource = new Uri(value);
image.EndInit();
ImageBehavior.SetAnimatedSource(Imagereference, image);
The 'value' is the location of your gif file such as "25.gif".
The Imagereference is the Image control you want to update. Also ensure you have the namespace referenced: using WpfAnimatedGif;

Maybe you can use Binding, something like
private string _dynamicGif = "test.gif";
public string DynamicGif
{
get { return _dynamicGif; }
private set
{
_dynamicGif = value;
RaisePropertyChanged("DynamicGif");
}
}
and
<Image gif:ImageBehavior.AnimatedSource="{Binding DynamicGif, UpdateSourceTrigger=PropertyChanged}" Width="20" />
Or, if it doesn't work, you can use MediaElement instead of Image, it won't require WPF Animated GIF. It's also pretty simple to use:
private Uri _imgSource = new Uri("test.gif");
public Uri ImgSource
{
get { return _imgSource; }
private set
{
_imgSource = value;
RaisePropertyChanged("ImgSource");
}
}
and
<MediaElement x:Name="gifImg" LoadedBehavior="Play" Width="20" Source="{Binding ImgSource}"/>
Hope this helps.

ImageFailed with GridView

I have a problem with GridView and multiple items. Each of the item has image in it, source is online image, bound to property, like this:
<GridView x:Name="gridView" Width="710" ItemTemplate="{StaticResource FirstTemplate}" AllowDrop="True" CanDragItems="True" CanReorderItems="True">
<DataTemplate x:Key="FirstTemplate">
<Grid HorizontalAlignment="Left" Width="306" Height="210">
<Border Background="White" Opacity="0.1"/>
<Image Stretch="Uniform" Width="190" Height="100" Margin="0,50,0,0" ImageFailed="ImageFailed" Source="{Binding ImagePath}"/>
</Grid>
</DataTemplate>
Image paths are like this:
www.example.com/images/1.png
www.example.com/images/2.png
www.example.com/images/3.png
and so on...
If some image not exist, for example www.example.com/images/29.png, I use the event ImageFailed, which change the source of the image to image that is located in my project (default image). Code in this event:
private void ImageFailed(object sender, ExceptionRoutedEventArgs e)
{
var image = sender as Image;
image.Source = new BitmapImage(new Uri("ms-appx:///Images/default.png"));
}
And this is working just fine, the default image is shown in the items that don't have images. But, when I scroll down the gridview, and then return to the beginning, images are messed up. Some items that had their images, now have the default image. Again when I scroll the gridview, and then return, again random changes with images.
Is this some cache problem? What could be the problem here? Or is there any better way of setting the default image source?

The source of your problem could be virtualization, i.e. reuse of item containers. When you replace a failed image by a fallback image in your ImageFailed handler, you are effectively replacing the Binding by a fixed value, so that the item container will later always show only the fallback image.
You may instead implement the ImageFailed handler in the view model, so that replacing the image with a fallback image won't break the Binding.
Add another property, e.g. Image to your item class
public class ImageItem
{
public string ImagePath { get; set; }
private BitmapImage image;
public BitmapImage Image
{
get
{
if (image == null)
{
image = new BitmapImage();
image.ImageFailed += (s, e) =>
image.UriSource = new Uri("ms-appx:///Images/default.png");
image.UriSource = new Uri(ImagePath);
}
return image;
}
}
}
and change the Binding to this:
<Image ... Source="{Binding Image}"/> // no ImageFailed handler here

Converted BitmapImage not displaying on Page

I am having a problem with my Windows Phone application. When I get the photo from a web service, I want to display it as an image on the page. The web service returns a byte[] as the image data.
Dispatcher.BeginInvoke(() =>
{
tempImage = new BitmapImage();
globalWrapper = (PhotoWrapper)JsonConvert.DeserializeObject(
response.Content, typeof(PhotoWrapper));
tempImage.SetSource(new MemoryStream(globalWrapper.PictureBinary, 0,
globalWrapper.PictureBinary.Length));
globalWrapper.ImageSource = tempImage;
PictureList.Items.Add(globalWrapper);
});
PictureList is a ListBox defined as:
<ListBox Name="PictureList" ItemsSource="{Binding}" Margin="0,0,0,0">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel>
<Button Click="details_Click">
<Button.Content>
<Image Source="{Binding ImageSource}"></Image>
</Button.Content>
</Button>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
Now, my question is, how do you receive a byte[] from a webservice as JSON and display it on the page? I feel like I am pretty close here but am missing something rather elementary.

If you're certain that the byte[] data is valid, it could be something to do with the CacheOption property of the BitmapUmage. This property controls when data is actually loaded from the stream into the bitmap. The default is OnDemand, which only loads data from the stream when the image is displayed. You might want to try the OnLoad option instead, which loads it immediately, allowing you to close the stream.
Dispatcher.BeginInvoke(() =>
{
globalWrapper = (PhotoWrapper)JsonConvert.DeserializeObject(
response.Content, typeof(PhotoWrapper));
tempImage = new BitmapImage();
tempImage.BeginInit();
tempImage.CacheOption = BitmapCacheOption.OnLoad;
tempImage.SetSource(new MemoryStream(globalWrapper.PictureBinary, 0,
globalWrapper.PictureBinary.Length));
tempImage.EndInit();
globalWrapper.ImageSource = tempImage;
PictureList.Items.Add(globalWrapper);
});