MDI Background image problem

Question

I have an application using c sharp and i added a background image for mdi form but when ever a form is loaded the mdi image is blinking why

Vilas Gite · Answer

@Zoran Is it possible to prevent flickering if we put these image files in Debug\Bin folder?

Erick Alvarado · Answer

Hello! I had the same problem . My solution is: In the event form ResizeBegin sets the property BackgroudImage in Noghing... next in the event ResizeEnd again sets the property with your image and add this line: ResizeRedraw = True Hola yo tenía el mismo problema. Mi solución es que en el evento  ResizeBegin de tu formulario establezcas la propiedad BackgroudImage en Nothing luego en el evento ResizeEnd vuelve a establecer la propiedad con la imagen que deseas de fondo y agrega esta línea: ResizeRedraw = True ====================== CODE ================================= Private Sub frmPrincipal_ResizeBegin(sender As Object e As EventArgs) Handles Me.ResizeBegin Me.BackgroundImage = Nothing End Sub Private Sub frmPrincipal_ResizeEnd(sender As Object e As EventArgs) Handles Me.ResizeEnd Me.BackgroundImage = My.Resources.fondo ResizeRedraw = True End Sub From Costa Rica Pura Vida!!!

Zoran Horvat · Answer

Jayakrishnan Did setting DoubleBuffered to true resolve the flickering problem? Zoran

Zoran Horvat · Answer

I think it will not help. You can try this code for instance: using System.Drawing; using System.Windows.Forms; namespace ImageTest { class Program { private class MyForm: Form { public MyForm() { _backgroundImage = new Bitmap(500 500); using (Graphics gr = Graphics.FromImage(_backgroundImage)) { gr.FillRectangle(new SolidBrush(Color.Gray) new Rectangle(0 0 500 500)); gr.FillEllipse(new SolidBrush(Color.DarkRed) new Rectangle(0 0 500 500)); } this.BackgroundImage = _backgroundImage; } protected override void OnFormClosed(FormClosedEventArgs e) { base.OnFormClosed(e); _backgroundImage.Dispose(); } private Image _backgroundImage; } static void Main(string[] args) { MyForm f = new MyForm(); f.ShowDialog(); } } } Wait for it to open the form and then maximize the form. You'll see flickering. It comes from the form acting upon Window message to draw background - instead of drawing the image immediately it first draws background in solid brush. This is probably done because .NET doesn't know whether the background image contains some transparent parts etc. so Form tries to be sure that its background will be solidly filled even after the image is applied. Anyway that kind of worry leads to flickering. Now modify MyForm and add this method: protected override void OnPaintBackground(PaintEventArgs e) { //base.OnPaintBackground(e); for (int x = 0; x for (int y = 0; y e.Graphics.DrawImage(_backgroundImage new Point(x y)); } And repeat the test - open the form then maximize it resize it manually etc. You'll see that flickering has gone. Off course if you uncomment the base.OnPaintBackground call flickering will be back again. This example shows how to stop flickering in some cases but in every particular case it is up to the programmer to know what should be done by the form. Same effect in this case can be obtained by adding this to the constructor: this.DoubleBuffered = true; However you don't have DoubleBuffered property available at all times. If you're coding custom control then your control will be instantiated by a form which might have DoubleBuffered set to false and you can't do anything about it. Zoran

Zoran Horvat · Answer

Welcome to the club... First try setting form's DoubleBuffered property to true. It is a protected property which is by default set to false. So you have to set it to true in form's constructor. Zoran

jayakrishnan Morayur · Answer

how can i exceed Flickering

Zoran Horvat · Answer

That is probably because form draws its background (in solid color) and only then draws the image. Flickering is an eternal problem in .NET. Zoran