I have textbox and button in the left side,i need to write new name for selected item in listbox, and after clicking on Save button my selected item's title must change.What should i write in Save button click?This is screenshot ` WPF [ ^ ]
This is my all code`
public partial class MainWindow : Window public MainWindow() InitializeComponent(); DataContext = this ; public ObservableCollection<MyPicture> MyPictures { get ; } = new ObservableCollection<MyPicture>(); private void Button_Click( object sender, RoutedEventArgs e) OpenFileDialog op = new OpenFileDialog() Title = " Select picture(s)" , Filter = " All supported graphics|" + " *.jpg;*.jpeg;*.png|" + " JPEG (*.jpg;*.jpeg)|" + " *.jpg;*.jpeg|" + " Portable Network Graphic (*.png)" + " |*.png" , InitialDirectory = Environment.GetFolderPath( Environment.SpecialFolder.MyPictures), Multiselect = true if (op.ShowDialog() == true ) paste(op.FileNames.Select(f => new MyPicture Url = new Uri(f, UriKind.Absolute), Title = System.IO.Path.GetFileName(f) private void paste(IEnumerable<MyPicture> newPictures) foreach ( var item in newPictures) MyPictures.Add(item); public class MyPicture public Uri Url { get ; set ; } public string Title { get ; set ; } What I have tried:
I have written like this, but it's not working.
private void savebutton_Click( object sender, RoutedEventArgs e) lb.SelectedItem= textBox.Text; < /Grid.RowDefinitions > < Image Source =" {Binding Url}" / > < TextBlock MouseDown =" txtblk_MouseDown" Grid.Row =" 1" Text =" {Binding Title}" / > < TextBox LostFocus =" txtbox_LostFocus" Grid.Row =" 1" Text =" {Binding Title, Mode=TwoWay}" Visibility =" Collapsed" / > < /Grid > < /DataTemplate > < /ListBox.ItemTemplate >
and add the following code to your code-behind:
private void txtblk_MouseDown( object sender, System.Windows.Input.MouseButtonEventArgs e) TextBox txt = (TextBox)((Grid)((TextBlock)sender).Parent).Children[2]; txt.Visibility = Visibility.Visible; ((TextBlock)sender).Visibility = Visibility.Collapsed; private void txtbox_LostFocus( object sender, RoutedEventArgs e) TextBlock tb = (TextBlock)((Grid)((TextBox)sender).Parent).Children[1]; tb.Visibility = Visibility.Visible; ((TextBox)sender).Visibility = Visibility.Collapsed; For the changed to be reflected using data binding, you need to change the MyPicture class as follows:
public class MyPicture : ObservableBase public Uri Url { get ; set ; } // filename of image private string title; public string Title get { return title; } set { Set( ref title, value ); } and add the following class to support the INotifyPropertyChanged interface:
public abstract class ObservableBase : INotifyPropertyChanged public void Set<TValue>( ref TValue field, TValue newValue, [CallerMemberName] string propertyName = " " ) if (EqualityComparer<TValue>.Default.Equals(field, default (TValue)) || !field.Equals(newValue)) field = newValue; PropertyChanged?.Invoke( this , new PropertyChangedEventArgs(propertyName)); public event PropertyChangedEventHandler PropertyChanged; The INotifyPropertyChanged interface notifies the data binding system there is a change when the PropertyChanged event is raised. I've wrapped this up in a base class making the usage very simple. You can see this in the Title property Set method of the MyPicture class.
To use, click on the Picture's title text and you will be able to edit it. Once you click outside the editing TextBox, the changes will automatically be applied. SelectedItem returns an object, not an instance of MyPicture. What you need to do is convert the selected object into MyPicture and then assign the text to the value. Something like this: private void UpdateTitle() if (lb.SelectedItem == null ) return ; MyPicture picture = lb.SelectedItem as MyPicture; if (picture != null ) picture.Title = textBox.Text;

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