WPF popup wont close even with StaysOpen="false"

Question

I am trying to achieve the following:

1. User brings up a context menu in a datagrid.
2. User selects a context menu item which then opens a popup and displays some information.
3. when the user clicks anywhere else in the application, not in the popup, the popup closes.

Everything works fine until I come to closing the popup.

From searching elsewhere I am aware that I need Staysopen to be set to false ( which it is) I also read the best way is to bind the IsOpen value to a property in the view model and set its binding to 2 way ( also done )

As a side note I have found that if I add a textbox and click inside the box, when I then click outside the popup it closes as desired.

Another thing I unsuccessfully tried as a workaround was to programmatically set the keyboard focus on the text box to get the "autoclose" functionality I desired.

Here is code:

xaml -

<Popup Name="PredictionsPopup" Height="200" Width="200" AllowsTransparency="false" StaysOpen="False" IsOpen="{Binding DisplaySummaryPopup, Mode=TwoWay}">
            <StackPanel Background="{DynamicResource {x:Static SystemColors.ControlBrushKey}}">
                <TextBlock Text="here is some stuff" />
                <TextBox Name="hiddenBox" Text="moo"/>
            </StackPanel>         
        </Popup>

Codebehind that sets the property on the viewmodel when the menu item is selected.

 private void CurrentPredicitions_OnClick(object sender, RadRoutedEventArgs e)
        {

            PredictionsPopup.Placement = PlacementMode.MousePoint;
            ViewModel.DisplaySummaryPopup = true;

        }

Viewmodel property

public bool? DisplaySummaryPopup
        {
            get
            {
                return this.displaySummaryPopup;
            }

            set
            {
                this.displaySummaryPopup = value;
                RaisePropertyChanged(() => this.DisplaySummaryPopup);
            }
        }

Please let me know if you need anymore details.

Answer 1

Here you have a working example:

MainWindow XAML:

<Window x:Class="WpfApplication2.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <Popup Name="PredictionsPopup" Height="200" Width="200" AllowsTransparency="false" StaysOpen="False" IsOpen="{Binding DisplaySummaryPopup, Mode=TwoWay}">
            <StackPanel Background="Red">
                <TextBlock Text="here is some stuff" />
                <TextBox Name="hiddenBox" Text="moo"/>
            </StackPanel>
        </Popup>
        <DataGrid AutoGenerateColumns="False"  Name="dataGrid1"  IsReadOnly="True" >
            <DataGrid.Columns>
                <DataGridTextColumn Header="Site"  Width="150" />
                <DataGridTextColumn Header="Subject"  Width="310" />
            </DataGrid.Columns>
            <DataGrid.ContextMenu>
                <ContextMenu>
                    <MenuItem Header="Click Me" Click="ButtonBase_OnClick">                     
                    </MenuItem>
                </ContextMenu>
            </DataGrid.ContextMenu>
        </DataGrid>
      

    </Grid>
</Window>

MainWindow cs :

 public MainWindow()
        {
            InitializeComponent();
            DataContext = new TestViewModel();
        }

        private void ButtonBase_OnClick(object sender, RoutedEventArgs e)
        {
            PredictionsPopup.Placement = PlacementMode.MousePoint;
            PredictionsPopup.IsOpen = true;

        }

ViewModel:

  public class TestViewModel : INotifyPropertyChanged
    {
        private bool _displaySumarry;
        public bool DisplaySummaryPopup
        {
            get { return _displaySumarry;  }
            set
            {
                _displaySumarry = value;
                OnPropertyChanged();
            }
        }

        public event PropertyChangedEventHandler PropertyChanged;

        protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
        {
            var handler = PropertyChanged;
            if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
        }
    }

I think that your implementation for INotifyPropertyChanged is the one which causes the problem. I tried myself the code and is working now.

Answer 2

I faced same problem a few times. Every time it was occuring, when a popup was changing its "isOpen" property to true from an event, which was raised from listview or datagrid element, like selectedItemChanged event, or items mouseUp event. I don't know reason, however resolved it by opening the popup from another task with code as below:

Task.Run(()=> Dispatcher.Invoke( () => myPopup.IsOpen = true));

Dispatcher is used to avoid an exception from changing any GUI object property from another than the main thread.

Answer 3

For me, the solution was to add this line in the constructor of the popup's code-behind:

LostFocus += delegate { this.IsOpen = false; };

Many hours were spent, when such a quickie line was all it took :)

Answer 4

Had the same problem. The reason was, that the toggle button's ClickMode property was set to "Press". Setting it back to "Release" solved it :).

Answer 5

After trying to track this problem down I worked out that the issue is something to do with the context menu. I know this because as per the answer above instead of launching my popup via a context menu I launched it from a test button and all worked as expected.

I still don't know the exact reason for this issue but I think its something to do with the fact that the context menu is itself a subclass of popup and the focus isn't being set correctly on the new popup, so it never detects popup loss and closes.

To get round my problem I have added a close button to the popup, and then whenever the active tab in the control that hosts the popup changes it fires an event that the popup picks up and closes.