[RESOLVED] Center backgroundimage in MDI

[dmr]

Hi all!
By just adding an image to bgimg it is tiled over the whole form.
Is there a fast way to center the backgroundimage of a MDI-form ?

I fixed it by using a graphics object filled with my backgroundcolor and drew the image to the center and redrew it to bgimg of the MDI. But this is kinda slow.

I can't imagine that MS does not support centering by default (I use .NET/1.0).



Thanks in advance!

[dynamic_sysop]

if you make a seperate image to hold the centred image , this seems quite ok ( hope it helps , only quickly knocked it up )

public Bitmap imgCustom = null;
        public Image im = null;
        public MdiClient Client = null;
        public System.Drawing.GraphicsUnit gUnit = System.Drawing.GraphicsUnit.Pixel;
 
        private void Form1_Load(object sender, System.EventArgs e)
        {
            foreach(MdiClient mdi in Controls)
            {
                Client = (MdiClient)mdi;
                im = Image.FromFile(@"C:\vb_logo.gif");
                imgCustom = new Bitmap(Screen.PrimaryScreen.WorkingArea.Width, Screen.PrimaryScreen.WorkingArea.Height);
                Graphics grphcs = Graphics.FromImage(imgCustom);
                RectangleF r = imgCustom.GetBounds(ref gUnit);
                grphcs.FillRectangle(new SolidBrush(Client.BackColor),r);
                grphcs.DrawImage(im ,new Point(((0 + Client.Width) - (im.Width)) / 2, Convert.ToInt32(((0 + Client.Height) - (im.Height / 2)) / 2.5)));
                grphcs.Save();
                this.BackgroundImage = imgCustom;
            }
        }
 
        private void Form1_Resize(object sender, System.EventArgs e)
        {
            /// to ensure we center the image when the form gets resized.
            if(this.WindowState!=System.Windows.Forms.FormWindowState.Minimized)
            {
                Graphics grphcs = Graphics.FromImage(imgCustom);
                RectangleF r = imgCustom.GetBounds(ref gUnit);
                grphcs.FillRectangle(new SolidBrush(Client.BackColor),r);
                grphcs.DrawImage(im ,new Point(((0 + Client.Width) - (im.Width)) / 2, Convert.ToInt32(((0 + Client.Height) - (im.Height / 2)) / 2.5)));
                grphcs.Save();
                this.BackgroundImage = imgCustom;
                this.Refresh();
            }
        }

[dmr]

Hi, thanks alot for you soon reply.
I combined yours and mine code and now it seems to work fine.

        private void Form1_Load(object sender, System.EventArgs e)
        {
            foreach(MdiClient mdi in Controls)
            {

The marked line may fail, when you place controls that differ the type of MdiClient (-> almost everything...) on the MDI.


Finally, for everyone who might be interested in, I'm using the following code:

MDI-Form mdi
Image imgCustom = null
PictureBox picBackground (on MDI; visible = false; containing the image to center)

      private void mdi_Resize(object sender, System.EventArgs e)
      {
      
         // to ensure we center the image when the form gets resized
         if (this.WindowState != System.Windows.Forms.FormWindowState.Minimized)
         {

            if (imgCustom == null)
               imgCustom = new Bitmap(Screen.PrimaryScreen.WorkingArea.Width, Screen.PrimaryScreen.WorkingArea.Height);

            RectangleF r = imgCustom.GetBounds(ref gUnit);
            Graphics g = Graphics.FromImage(imgCustom);

            g.FillRectangle(new SolidBrush(this.BackColor), r);
            g.DrawImage(picBackground.Image, (this.ClientRectangle.Width - picBackground.Image.Width) / 2, (this.ClientRectangle.Height - picBackground.Image.Height) / 2);
            g.Save();

            this.BackgroundImage = imgCustom;
            this.Refresh();
         
         }
      }