How can i Show popup on button click and Hide it on second click or user clicks outside (StaysOpen="False")

xaml

(summerbreeze384) #1

I have a button and want to show a popup when it’s clicked, and hide it when it’s clicked second time. with StaysOpen="False".
now the issue is when the user clicks on the button again, that will Hide and show the Popup at the same time.

now what I want is there is any direct way to make the popup Show when the user clicks on the button. and hidden when the user clicks the same button again or when clicks outside (mainly using StaysOpen='False')?

thanks


(Daniel) #2

Not entirely sure, just going to guess here. You say that…

  • The user clicks the button once. StaysOpen='True' should make a popup.

  • The user clicks the button again. StaysOpen='False' should make the popup disappear.

  • The user clicks the button a third time. The pop up appears and disappear straight away meaning StaysOpen='True' and then immediately 'False'.

Did I get that right?

Is that what’s going on?


(Yassine) #3

I believe @summerbreeze384 is right, that’s a very common issue encountered by newbie WPF designers.

The problem is that the behavior needed is this simple:

  1. When button clicked, the Popup should open.
  2. When the button clicked again (and the popup still open) it should close it.

it’s as simple as that!

but instead WPF’s default behavior is this:

  1. When the button is clicked, it Opens the popup.
  2. When the button is clicked again, the button raises the MouseDown event and the Popup closes on that event.
  3. Afterwards the Clicked event is raised, but since the Popup is already closed, it will open it again. Thus causing for the Popup to be closed & opened immediately.

(Yassine) #5

Here is a solution i could find working perfect:

Unfortunately there is no direct/clean way to do that. :frowning: but here is a little trick to get same behavior :slight_smile:

Use Popup.StaysOpen=False, and use data binding on the Popup.IsOpen property to the ToggleButton.IsChecked property (in the below code example, assume a ToggleButton named OpenPopupButton):

<Popup
    Name="PresetPopup"
    IsOpen="{Binding ElementName=OpenPopupButton, Path=IsChecked}"
    PlacementTarget="{Binding ElementName=OpenPopupButton}"
    AllowsTransparency="True"
    PopupAnimation="Slide"
    StaysOpen="False" />

This worked great, until you try to use the ToggleButton to hide the Popup. What would happen is that the Popup.StaysOpen property would collide with the data binding to the Popup.IsOpen property, and cause the Popup to never close when you click on the ToggleButton.

The solution i found was to define the ToggleButton.MouseEnter and ToggleButton.MouseLeave properties and modify the Popup.StaysOpen property whenever the user was using the ToggleButton.

Here is the button XAML:

<ToggleButton
            Name="OpenPopupButton"
            Width="100"
            Height="28"
            MouseEnter="OpenPopupButton_MouseEnter"
            MouseLeave="OpenPopupButton_MouseLeave" />

MouseEnter and MouseLeave Event handlers:

private void OpenPopupButton_MouseEnter(object sender, MouseEventArgs e)
{
    PresetPopup.StaysOpen = true;
}
 
private void OpenPopupButton_MouseLeave(object sender, MouseEventArgs e)
{
    PresetPopup.StaysOpen = false;
}

Hope this helps solving your problem.


(Yay) #6

I used the above Answer but it seems to have a little bug on it.

The problem asserts itself only when the Popup is expanded (and StaysOpen=false).

Here is how you reproduce it:

  1. The user toggles the ToggleButton (which expands the Popup)
  2. The user (accidentally) moves the mouse off the ToggleButton.
  3. The user goes to toggle the ToggleButton (to close the Popup manually)

At this point, the Popup collapses, and then immediately expands (the same symptoms as the original symptoms above).

Here is what is happening:
If you have StaysOpen set to false, the Popup internally captures the mouse (so that it knows if the user has clicked elsewhere … so that it can collapse the Popup).

However, what that does is causes us not to get the MouseEnter above (and thus the necessary and needed StaysOpen=true behavior for manually toggling the Popup open and closed).

Therefore, when the user goes to toggle the Popup closed manually (step 3 above), the captured mouse tells the Popup to collapse … however, then the ToggleButton kicks in and re-toggles the Popup open.

Here is the solution:
You need to make the ToggleButton not respond to the mouse when the Popup is expanded. In this way, only the StaysOpen=false, mouse capture functionality kicks in … and the Popup collapses … and doesn’t expand again.

How do you do this? You need to bind the IsHitTestVisible property of the ToggleButton to the !IsOpen property of the Popup.

To get the !IsOpen (Inverted IsOpen Value) you need to use a IValueConverter.

Here is the resulting Code:
1. XAML

<ToggleButton
            Name="TestButton"
            Width="100"
            Height="28"
            IsHitTestVisible="{Binding ElementName=PresetPopup, Path=IsOpen, Mode=OneWay, Converter={StaticResource BoolInverterConverter1}}" />

2. C# Converter Code behind

public class BoolInverterConverter : IValueConverter
{
    #region IValueConverter Members
    
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        if (value is bool)
        {
            return !((bool)value);
        }
        return null;
    }
    
    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        throw new NotImplementedException();
    }
    
    #endregion
}