UserControl PreviewMouseLeftButtonUp problem - wpf

Question

I have a UserControl in WPF. I also have a Borderless window. To move it- I use DragMove.
But- to get a click event in the user control- I use the PreviewMouseLeftButtonUp event and capture the mouse on UserControl_MouseEnter.
The problem is- that if I click the control, then move the window- the event can be triggered also when clicking near the control, not on it.
Here is my code:
UserControl1.xaml:
<UserControl x:Class="WpfApplication1.UserControl1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300" MouseEnter="UserControl_MouseEnter" MouseLeave="UserControl_MouseLeave">
<Grid>
</Grid>
</UserControl>
UserControl1.xaml.cs:
public partial class UserControl1 : UserControl
{
public UserControl1()
{
InitializeComponent();
}
private void UserControl_MouseEnter(object sender, MouseEventArgs e)
{
CaptureMouse();
}
private void UserControl_MouseLeave(object sender, MouseEventArgs e)
{
ReleaseMouseCapture();
}
}
MainWindow.xaml:
<Window x:Class="WpfApplication1.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" xmlns:my="clr-namespace:WpfApplication1" WindowStyle="None" MouseLeftButtonDown="Window_MouseLeftButtonDown">
<Grid>
<my:UserControl1 Margin="39,29,380,199" Background="Red" PreviewMouseLeftButtonUp="UserControl1_PreviewMouseLeftButtonUp">
</my:UserControl1>
</Grid>
</Window>
MainWindow.xaml.cs:
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private void Window_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
DragMove();
}
private void UserControl1_PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
MessageBox.Show("Hello World");
}
}
If you run this app- you'll see that if you click on the control, then drag the window, then click near the control (the side may vary)- it will trigger the PreviewMouseLeftButtonUp event even though you didn't click on the control itself.
Any ideas how to solve this?
Thanks!

Answer 1

I asked around, and found that to solve the problem, I need to change the User control's events:
Instead of MouseLeave- I use MouseMove.
private void UserControl_MouseEnter(object sender, MouseEventArgs e)
{
if (this.IsEnabled)
CaptureMouse();
}
private void UserControl_MouseMove(object sender, MouseEventArgs e)
{
Point mouseposition = e.GetPosition(this);
if (mouseposition.X < 0 || mouseposition.Y < 0 || mouseposition.X > this.ActualWidth || mouseposition.Y > this.ActualHeight)
ReleaseMouseCapture();
}