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Prevent Double-Click Maximization on RadWindow


Product Version 2021.3.914
Product RadWindow for WPF


How to prevent maximization on the RadWindow control, when the title bar is double-clicked.


To achieve this, you could subscribe to the HostCreated event of the Window control, and inside of it, set the SourceInitialized event of the HostWindow property provided by the HostWindowCreatedEventArgs event arguments. Additionally, several fields and methods from the Win32 API would be required, which are present in the below code snippet.

public partial class MainWindow : RadWindow 
    public MainWindow() 
        this.HostCreated += MainWindow_HostCreated; 
    private static extern int GetWindowLong(IntPtr hWnd, int nIndex); 
    private static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong); 
    private const int GWL_STYLE = -16; 
    private const int WS_MAXIMIZEBOX = 0x10000; 
    private void MainWindow_HostCreated(object sender, HostWindowCreatedEventArgs e) 
        e.HostWindow.SourceInitialized += Window_SourceInitialized; 
    private void Window_SourceInitialized(object sender, EventArgs e) 
        IntPtr hwnd = new WindowInteropHelper((Window)sender).Handle; 
        var value = GetWindowLong(hwnd, GWL_STYLE); 
        SetWindowLong(hwnd, GWL_STYLE, (int)(value & ~WS_MAXIMIZEBOX)); 
Public Partial Class MainWindow 
    Inherits RadWindow 
    Public Sub New() 
        Me.HostCreated += AddressOf MainWindow_HostCreated 
    End Sub 
    Private Shared Function GetWindowLong(ByVal hWnd As IntPtr, ByVal nIndex As Integer) As Integer 
    Private Shared Function SetWindowLong(ByVal hWnd As IntPtr, ByVal nIndex As Integer, ByVal dwNewLong As Integer) As Integer 
    Private Const GWL_STYLE As Integer = -16 
    Private Const WS_MAXIMIZEBOX As Integer = &H10000 
    Private Sub MainWindow_HostCreated(ByVal sender As Object, ByVal e As HostWindowCreatedEventArgs) 
        e.HostWindow.SourceInitialized += AddressOf Window_SourceInitialized 
    End Sub 
    Private Sub Window_SourceInitialized(ByVal sender As Object, ByVal e As EventArgs) 
        Dim hwnd As IntPtr = New WindowInteropHelper(CType(sender, Window)).Handle 
        Dim value = GetWindowLong(hwnd, GWL_STYLE) 
        SetWindowLong(hwnd, GWL_STYLE, CInt((value And Not WS_MAXIMIZEBOX))) 
    End Sub 
End Class 
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