Windows Metro Style app data binding - data-binding

Question

I have a requirement to load images from a folder in the project to a stackpanel. Under each image a name should also be shown. The image folder can change at any time and the number of images can also change.(with a maximum of 50 images) I want to know if I can use data binding to handle this. I thought of having image ID's, their sources and the name for each image in an XML so that I can change that XML file whenever the image folder changes, without changing the rest of the code. Is that feasible? If so how? Can someone please guide me? Thank you in advance.

Answer 1

One solution would be to use a Filepicker to let the user select the images inside the folder, and then bind the selected images to an Itemscontrol. That itemscontrol can then be put inside the Stackpanel. Here's a quick sample using that solution.
Here's the codebehind for picking the image files:
private List<EditableImage> availableImagesList = new List<EditableImage>();
private async void FilePicker_Clicked(object sender, RoutedEventArgs e)
{
FileOpenPicker openPicker = new FileOpenPicker();
openPicker.ViewMode = PickerViewMode.List;
openPicker.SuggestedStartLocation = PickerLocationId.DocumentsLibrary;
//TODO: add supported image file types
openPicker.FileTypeFilter.Add("jpg,png,gif");
// We prompt the user to pick one or more files
IReadOnlyList<StorageFile> files = await openPicker.PickMultipleFilesAsync();
if (files.Count > 0)
{
availableImages.DataContext = null;
String fp = ""; // The path of the picked image
int index = availableImagesList.Count;
foreach (StorageFile file in files)
{
// Copying the selected image to local app data folder
//TODO: check if the selected file is actually and image
if (file != null )
{
StorageFile fileCopy = await file.CopyAsync(ApplicationData.Current.LocalFolder, file.DisplayName + file.FileType, NameCollisionOption.ReplaceExisting);
fp = fileCopy.Path;
}
//Creating the image
CustomImage picToAdd = new CustomImage(index+1, file.DisplayName, fp);
//Adding the image as an UI element to the app bar
availableImagesList.Add(picToAdd);
}
availableImages.DataContext = availableImagesList;
}
}
The CustomImage model:
public class CustomImage
{
private static Uri _baseUri = new Uri("ms-appx:///");
private int _id;
public int Id
{
get { return _id; }
set
{
this.SetProperty(ref this._id, value);
}
}
private string _name;
public string Name
{
get { return _name; }
set
{
this.SetProperty(ref this._name, value);
}
}
private string _imgPath;
public string ImgPath
{
get { return _imgPath; }
set
{
this.SetProperty(ref this._imgPath, value);
}
}
private String _imagePath = null;
private ImageSource _image = null;
public ImageSource Image
{
get
{
if (this._image == null && this._imagePath != null)
{
this._image = new BitmapImage(new Uri(CustomImage._baseUri, this._imagePath));
}
return this._image;
}
set
{
this._imagePath = null;
this.SetProperty(ref this._image, value);
}
}
public void SetImage(String path)
{
this._image = null;
this._imagePath = path;
this.OnPropertyChanged("Image");
}
public CustomImage(int id, string name, string imagepath)
{
SetImage(imagepath);
_id = id;
_name = name;
}
}
Here's the XAML for the ItemsControl inside the Stackpanel:
<StackPanel x:Name="loadedImages" HorizontalAlignment="Left" Orientation="Horizontal">
<!--Displaying the selected images in stackpanel-->
<ItemsControl ItemsSource="{Binding}" ItemsPanel="{StaticResource LoadedItemsPanel}">
<ItemsControl.ItemTemplate>
<!--The template for each object that is displayed as an UI element-->
<DataTemplate>
<Grid Height="88" Margin="2,0" Width="88" >
<Image Source="{Binding Image}"/>
<TextBlock Text="{Binding Name}"/>
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</StackPanel>
In your page resources, you must also define:
<ItemsPanelTemplate x:Key="LoadedItemsPanel">
<WrapGrid Orientation="Horizontal"/>
</ItemsPanelTemplate>