GDI Refresh Problem

[Franco Gustavo]

Hi,

How can I execute 2 GDI steps without update the screen and update them
togheter?.

Basically I have a form and I want to change the Form Region and change the
Form Location, later show the changes on the screen.

On the Following code you can see that the code is executed but where the
window was there is the rest of the window that wasn't cleaned, if you move
a window over it it disapears.

I want to avoid see every change I do on the screen because I'm running many
changes a seconds (Animation)

I tried many ways but still I can get a way to work.

Here is the small code. "See Next Post" (Uncomment try1 or try2)
Thanks,

namespace PrototipesAndTe sting
{
public class AnimateNoFlick : System.Windows. Forms.Form
{
#region enums
public enum SetWindowPosFla gs
{
SWP_NOSIZE = 0x0001,
SWP_NOMOVE = 0x0002,
SWP_NOZORDER = 0x0004,
SWP_NOREDRAW = 0x0008,
SWP_NOACTIVATE = 0x0010
}
#endregion

#region WINAPIs
[DllImport("user 32.dll", CharSet=CharSet .Auto)]
private static extern bool SetWindowPos(In tPtr hWnd, IntPtr
hWndInsertAfter , int x, int y, int Width, int Height, SetWindowPosFla gs
flags);
[DllImport("User 32.dll", CharSet=CharSet .Auto)]
private static extern int SetWindowRgn(In tPtr hWnd, IntPtr hRgn, bool
redraw);
[DllImport("user 32.dll", CharSet=CharSet .Auto)]
private static extern int InvalidateRect( IntPtr hWnd, IntPtr rc, int
bErase);
[DllImport("user 32.dll", CharSet=CharSet .Auto)]
private static extern bool UpdateWindow(In tPtr hWnd);
#endregion

#region Variables Declaration
private System.Windows. Forms.Button button1;
private System.Componen tModel.Containe r components = null;
#endregion

#region Constructors
public AnimateNoFlick( )
{
InitializeCompo nent();
}
#endregion

#region Initialization And Disposing
protected override void Dispose( bool disposing )
{
if( disposing )
{
if(components != null)
{
components.Disp ose();
}
}
base.Dispose( disposing );
}

#region Windows Form Designer generated code
private void InitializeCompo nent()
{
this.button1 = new System.Windows. Forms.Button();
this.SuspendLay out();
//
// button1
//
this.button1.Lo cation = new System.Drawing. Point(96, 64);
this.button1.Na me = "button1";
this.button1.Ta bIndex = 2;
this.button1.Te xt = "button1";
this.button1.Cl ick += new System.EventHan dler(this.butto n1_Click);
//
// AnimateNoFlick
//
this.AutoScaleB aseSize = new System.Drawing. Size(5, 13);
this.ClientSize = new System.Drawing. Size(280, 262);
this.Controls.A dd(this.button1 );
this.Location = new System.Drawing. Point(300, 100);
this.Name = "AnimateNoFlick ";
this.StartPosit ion = System.Windows. Forms.FormStart Position.Manual ;
this.Text = "AnimateNoFlick ";
this.ResumeLayo ut(false);

}
#endregion

private void button1_Click(o bject sender, System.EventArg s e)
{
bool bResult;
int iResult;

Rectangle stepRec = new Rectangle(300, 500, this.Width,
this.Height);
Region region = new Region(new Rectangle(30,30 , 200, 200));

Graphics graphics = this.CreateGrap hics();
IntPtr ptr = region.GetHrgn( graphics);
graphics.Dispos e();

//Try 1
//bResult = SetWindowPos(th is.Handle, IntPtr.Zero, stepRec.X,
stepRec.Y, stepRec.Width, stepRec.Height, SetWindowPosFla gs.SWP_NOZORDER |
SetWindowPosFla gs.SWP_NOACTIVA TE | SetWindowPosFla gs.SWP_NOREDRAW );
//iResult = SetWindowRgn(th is.Handle, ptr, true);

//Try 2
iResult = SetWindowRgn(th is.Handle, ptr, false);
bResult = SetWindowPos(th is.Handle, IntPtr.Zero, stepRec.X,
stepRec.Y, stepRec.Width, stepRec.Height, SetWindowPosFla gs.SWP_NOZORDER |
SetWindowPosFla gs.SWP_NOACTIVA TE);
InvalidateRect( this.Handle, IntPtr.Zero, 1);
UpdateWindow(th is.Handle);
Application.DoE vents();
}
#endregion
}
}