#1,105 – Using Application’s Windows Collection to Interact with Other Windows
July 1, 2014 1 Comment
You can use the Application object’s Windows property to get a list of all active windows. If you then cast to your specific subclass of Window, you can interact with the various child windows.
Suppose that we have a main window with a button for creating other windows.
private void btnCreate_Click(object sender, RoutedEventArgs e)
{
OtherWindow ow = new OtherWindow();
ow.Show();
}
Assume that the child windows have a TextBox that binds to a property in the code-behind.
<TextBox Text="{Binding SomeText, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
Margin="10" Height="25"/>
The code-behind would look like this:
public partial class OtherWindow : Window, INotifyPropertyChanged
{
public OtherWindow()
{
InitializeComponent();
this.DataContext = this;
}
private string someText;
public string SomeText
{
get { return someText; }
set
{
someText = value;
RaisePropChanged("SomeText");
}
}
public event PropertyChangedEventHandler PropertyChanged = delegate { };
private void RaisePropChanged(string prop)
{
PropertyChanged(this, new PropertyChangedEventArgs(prop));
}
}
We can now get information on all child windows as shown below (this is an event handler for another button on the main window).
private void btnList_Click(object sender, RoutedEventArgs e)
{
StringBuilder sb = new StringBuilder();
foreach (Window w in Application.Current.Windows)
{
OtherWindow ow = w as OtherWindow;
if (ow != null)
sb.AppendLine(ow.SomeText);
}
MessageBox.Show(sb.ToString());
}
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