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Winforms - DoubleBuffering / Panel Content Alignment
f#
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        let make_color_widget () =                
            let color = new ColorDialog () in
            let color_b = new Button() in
            color_b.Text <- "Pick a Color..." ;
            let color_example = new Panel () in
            color_example.Height <- 25 ;
            color_example.Width <- 50 ;
            color_example.BackColor <- Color.Black ;
            color_b.Click.Add(fun _ -> if(color.ShowDialog() = DialogResult.OK) then color_example.BackColor <- color.Color) ;
            
            (* ============================================= *)
            
            let transparency = make_int_widget() in 
            (* Alias for a NumericUpDown which automatically sets DecimalPlaces to 0 *)
            transparency.Minimum <- System.Convert.ToDecimal(0.0) ;
            transparency.Maximum <- System.Convert.ToDecimal(100.0) ;
            transparency.Value <- System.Convert.ToDecimal(100.0) ;
            let get_transparency() = int_of_float (System.Convert.ToDouble(transparency.Value) /. 100.0 *. 255.0) in
            transparency.ValueChanged.Add(fun _ -> 
                let to_int = Byte.to_int  in
                let r,g,b = to_int color.Color.R, to_int color.Color.G, to_int color.Color.B in
                color_example.BackColor <- Color.FromArgb (get_transparency(), r, g, b)) ;
            
            let transparency_label = new Label() in
            transparency_label.Text <- "Opacity (%)" ;
            transparency_label.AutoSize <- true ;
                         
            (* ============================================= *)
            
            color.Color <- Color.FromArgb(get_transparency(), 0,0,0) ;
            
            (* ============================================= *)
            
            let container = new FlowLayoutPanel() in
            container.FlowDirection <- FlowDirection.LeftToRight  ;
            container.Controls.Add(color_b) ;
            container.Controls.Add(color_example) ;
            container.Controls.Add(transparency_label) ;
            container.Controls.Add(transparency) ; 
            container.Size <- container.PreferredSize ;
            (fun () -> color.Color), container

Is there a way (without using inheritance) to make a control doublebuffered ?

How can I align vertically the elements of the FlowLayoutPanel ?

Is there a way to convert between float/decimal without using System.Convert.ToDecimal(100.0) like using 100uy to get bytes, 100.0f to get float32 and so on ?

Thank you very much !!!

Julien

.

The first two questions relate to the Windows.Forms library and, while I do not doubt the familliarity of Windows.Forms people here you may be equally as likely to find a reply trying at more mainstream Windows.Forms forums.

As for the third, I believe there is currently no such syntax for decimals etc, but of course you can specify floats rather than ints by usig x.0. Of course, you can always define your own single-character functions to do the job if you're prepared to write then prefix and with a space:

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let d r = System.Convert.ToDecimal r
By on 9/8/2006 5:15 AM ()

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