Draw in MDIContainer won't work

I am trying to use DrawString and DrawRectangle in the interior area of an MDIContainer form. I can use these functions to draw on a regular form but not this Parent form.

In the Paint event of the form I have tried these ways to get the Graphics object:

Dim g As Graphics = Me.CreateGraphics
and
Dim g As Graphics = e.Graphics

Then using one of those objects used the following code:

g.FillRectangle(Brush, 200, 100, 100, 80)
g.DrawString("TestString", Font, Brush, 100, 100)

The code runs and does not throw an exception, but nothing is drawn onscreen.

Am I getting the Graphics object from the wrong place or is it just not possible to draw on that area of an MDIContainer

Walter

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Draw in MDIContainer won't work

Zcat
Complete code for Picture in MDI parent:

    Dim PanelImage As Bitmap
    Private WithEvents Myclient As Windows.Forms.MdiClient
    Private Declare Function GetWindow Lib "user32.dll" Alias "GetWindow" (ByVal hWnd As   Integer, ByVal uCmd As Integer) As Integer

    Private Sub YourForm_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Try
            Static GW_CHILD As Integer = 5
            Static GW_HWNDNEXT As Integer = 2
            Dim hndl As Integer = Me.GetWindow(Me.Handle.ToInt32, GW_CHILD)
            Dim success As Boolean = False
            While Not success
                Try
                    Myclient = DirectCast(Windows.Forms.MdiClient.FromHandle(New IntPtr(hndl)), MdiClient)
                    success = True
                Catch
                    hndl = Me.GetWindow(hndl, GW_HWNDNEXT)
                    success = False
                End Try
            End While
        Catch
            'ignore
        End Try

    End Sub

    Private Sub Myclient_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles Myclient.Paint
        Dim g As Graphics = e.Graphics
        Dim img As Image = groupPanelImage
        g.DrawImageUnscaled(img, 10, 10)
        e.Dispose()
    End Sub

    Private Sub Myclient_Resize(ByVal sender As Object, ByVal e As System.EventArgs) Handles Myclient.Resize
        Myclient.Refresh()
    End Sub

Private Sub MDIForm_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

PanelImage = CType(Bitmap.FromStream(System.Reflection.Assembly.GetExecutingAssembly().GetManifestResourceStream("Logo.gif")), Bitmap)
            groupPanelImage.MakeTransparent(Color.White)

End Sub

Dotnet67
GarethD25
Hi Walter,

Drawing on the MDIContainer form is not as simple as that.
This is because an MDI Container form actually uses an internal form on which the MDI Client forms are 'hosted'.

You need to do a little more plumbing if you want to paint something there.

There's a nice article about that on the vbaccelerator site:
http://www.vbaccelerator.com/home/NET/Code/Libraries/Windows/MDI_Client_Area_Painting/article.asp

Hope this helps,

Patrick.
Raheel
you do not need to use api calls to do this..

you can use this code:

private void Form1_Load(object sender, System.EventArgs e)
{
this.MdiClient.Paint += new PaintEventHandler(MdiClient_Paint);

}

//property to get the mdiclient control of a mdi form
protected MdiClient MdiClient
{
get
{
foreach (Control c in this.Controls)
{
if (c is MdiClient)
return c as MdiClient;
}

return null;
}
}

private void MdiClient_Paint(object sender, PaintEventArgs e)
{
e.Graphics.Clear (Color.Red);
}

//Roger
Draw in MDIContainer won't work

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