Xaml Image.Source在C＃中未更新

Question

I have some trouble with updating the source of an Image in Xaml. Im making a Windows Store App, and Im trying to set the source in my C# code. Basically, what my small program is doing is to let the user select a JPG file, and then copy this over to AppData folder. In my App, I want the picture the user have uploaded to show. Everything is working except the part where I show the image, this image does not want to change even if I provide a new source.

C# Code:

public sealed partial class MainPage : Page
{
    FileOpenPicker pickerSelect;
    FileSavePicker pickerSave;

    StorageFolder folder;
    StorageFile pic;

    public MainPage()
    {
        this.InitializeComponent();
        InitializePickers();
        InitializeProfilePicture();
    }

    private async void InitializeProfilePicture()
    {
        folder = Windows.Storage.ApplicationData.Current.LocalFolder;    
        pic = await folder.GetFileAsync("profile.jpg");        

        BitmapImage uri = new BitmapImage(new Uri(pic.Path, UriKind.Absolute));
        ProfilePic.Source = uri;

    }

    private void InitializePickers()
    {
        pickerSelect = new FileOpenPicker();
        pickerSave = new FileSavePicker();
        pickerSelect.FileTypeFilter.Add(".jpg");

    }


    private async void Upload_Click(object sender, RoutedEventArgs e)
    {
        StorageFile pictureSelect = await pickerSelect.PickSingleFileAsync();
        StorageFolder folder = Windows.Storage.ApplicationData.Current.LocalFolder;
        await pictureSelect.CopyAsync(folder, "profile.jpg", NameCollisionOption.ReplaceExisting);
        InitializeProfilePicture();
    }
}

In the method "InitializeProfilePicture" I create a new BitmapImage and I set ProfilePic to this. This code is just working once, if I run the InitializeProfilePicture in the start as I do now, and the user selects a new picture and uploads to the AppData folder, the image does not change (even though the picture is indeed uploaded). If I remove the method from the start and just keep it in the Button_Click method, the new uploaded picture will be the one showing. But uploading a new picture after ProfilePic have set it's source, it will not change.

Image in Xaml is just like this

Image Width="480" Height="640" x:Name="ProfilePic" Grid.Row="1" Grid.RowSpan="2"

.. And there is also a button here to run Upload_Click method, but thats it.

Any idea why this is happening?? Should it not be updated??

Answer 1

You could load a BitmapImage directly from file like this:

var imageFile = await picker.PickSingleFileAsync();
var bitmap = new BitmapImage();

using (var stream = await imageFile.OpenReadAsync())
{
    await bitmap.SetSourceAsync(stream);
}

ProfilePic.Source = bitmap;