Even worse behavior i just discovered with this code:
1. Run the form, maximize it.
2. use ALT-TAB to go somewhere else.
3. use ALT-TAB to come back to the form.
4. Try to use the file menu....
5. Try to restore down the form and resize it....
pretty mean behavior....
>Ok,
>
>After some testings, i found what is causing all my forms weird behaviors, it looks like there is a bug when playing with the opacity level of an MDI Parent. Here's the repro code:
>
>
>using System;
>using System.Drawing;
>using System.Collections;
>using System.ComponentModel;
>using System.Windows.Forms;
>using System.Data;
>
>namespace WindowsApplication1
>{
> /// <summary>
> /// Summary description for Form1.
> /// </summary>
> public class Form1 : System.Windows.Forms.Form
> {
> private System.Windows.Forms.MainMenu mainMenu1;
> private System.Windows.Forms.MenuItem menuItem1;
> private System.Windows.Forms.MenuItem menuItem2;
> /// <summary>
> /// Required designer variable.
> /// </summary>
> private System.ComponentModel.Container components = null;
>
> public Form1()
> {
> //
> // Required for Windows Form Designer support
> //
> InitializeComponent();
> ///// reset the opacity to 1 here
> ///// usually i would use a timer to do so
> ///// this line is not really the problem
> ///// and can stay here
> this.Opacity = 1d;
> //
> // TODO: Add any constructor code after InitializeComponent call
> //
> }
>
> /// <summary>
> /// Clean up any resources being used.
> /// </summary>
> protected override void Dispose( bool disposing )
> {
> if( disposing )
> {
> if (components != null)
> {
> components.Dispose();
> }
> }
> base.Dispose( disposing );
> }
>
> #region Windows Form Designer generated code
> /// <summary>
> /// Required method for Designer support - do not modify
> /// the contents of this method with the code editor.
> /// </summary>
> private void InitializeComponent()
> {
> this.mainMenu1 = new System.Windows.Forms.MainMenu();
> this.menuItem1 = new System.Windows.Forms.MenuItem();
> this.menuItem2 = new System.Windows.Forms.MenuItem();
> //
> // mainMenu1
> //
> this.mainMenu1.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
> this.menuItem1});
> //
> // menuItem1
> //
> this.menuItem1.Index = 0;
> this.menuItem1.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
> this.menuItem2});
> this.menuItem1.Text = "File";
> //
> // menuItem2
> //
> this.menuItem2.Index = 0;
> this.menuItem2.Text = "Test form";
> this.menuItem2.Click += new System.EventHandler(this.menuItem2_Click);
> //
> // Form1
> //
> this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
> this.ClientSize = new System.Drawing.Size(640, 481);
> this.IsMdiContainer = true;
> this.Menu = this.mainMenu1;
> this.Name = "Form1";
>
>///////////Removing this line will fix the problem /////////////////////
> this.Opacity = 0;
>////////////////////////////////////////////////////////////////////////
> this.Text = "Form1";
>
> }
> #endregion
>
> /// <summary>
> /// The main entry point for the application.
> /// </summary>
> [STAThread]
> static void Main()
> {
> Application.EnableVisualStyles();
> Application.DoEvents();
> Application.Run(new Form1());
>
> }
>
> private void menuItem2_Click(object sender, System.EventArgs e)
> {
> Form2 frm = new Form2();
> frm.MdiParent = this;
> frm.Show();
> }
> }
> public class Form2 : System.Windows.Forms.Form
> {
> private System.Windows.Forms.Label label1;
> private System.Windows.Forms.TextBox textBox1;
> private System.Windows.Forms.ListBox listBox1;
> private System.Windows.Forms.TextBox textBox2;
> private System.Windows.Forms.TextBox textBox3;
> private System.Windows.Forms.TextBox textBox4;
> private System.Windows.Forms.TextBox textBox5;
> private System.Windows.Forms.TextBox textBox6;
> /// <summary>
> /// Required designer variable.
> /// </summary>
> private System.ComponentModel.Container components = null;
>
> public Form2()
> {
> //
> // Required for Windows Form Designer support
> //
> InitializeComponent();
>
> //
> // TODO: Add any constructor code after InitializeComponent call
> //
> }
>
> /// <summary>
> /// Clean up any resources being used.
> /// </summary>
> protected override void Dispose( bool disposing )
> {
> if( disposing )
> {
> if(components != null)
> {
> components.Dispose();
> }
> }
> base.Dispose( disposing );
> }
>
> #region Windows Form Designer generated code
> /// <summary>
> /// Required method for Designer support - do not modify
> /// the contents of this method with the code editor.
> /// </summary>
> private void InitializeComponent()
> {
> this.label1 = new System.Windows.Forms.Label();
> this.textBox1 = new System.Windows.Forms.TextBox();
> this.listBox1 = new System.Windows.Forms.ListBox();
> this.textBox2 = new System.Windows.Forms.TextBox();
> this.textBox3 = new System.Windows.Forms.TextBox();
> this.textBox4 = new System.Windows.Forms.TextBox();
> this.textBox5 = new System.Windows.Forms.TextBox();
> this.textBox6 = new System.Windows.Forms.TextBox();
> this.SuspendLayout();
> //
> // label1
> //
> this.label1.Location = new System.Drawing.Point(8, 16);
> this.label1.Name = "label1";
> this.label1.TabIndex = 0;
> this.label1.Text = "A label";
> //
> // textBox1
> //
> this.textBox1.Location = new System.Drawing.Point(8, 40);
> this.textBox1.Name = "textBox1";
> this.textBox1.TabIndex = 1;
> this.textBox1.Text = "textBox1";
> //
> // listBox1
> //
> this.listBox1.Location = new System.Drawing.Point(8, 128);
> this.listBox1.Name = "listBox1";
> this.listBox1.Size = new System.Drawing.Size(248, 95);
> this.listBox1.TabIndex = 2;
> //
> // textBox2
> //
> this.textBox2.Location = new System.Drawing.Point(120, 40);
> this.textBox2.Name = "textBox2";
> this.textBox2.TabIndex = 3;
> this.textBox2.Text = "textBox2";
> //
> // textBox3
> //
> this.textBox3.Location = new System.Drawing.Point(8, 64);
> this.textBox3.Name = "textBox3";
> this.textBox3.TabIndex = 4;
> this.textBox3.Text = "textBox3";
> //
> // textBox4
> //
> this.textBox4.Location = new System.Drawing.Point(120, 64);
> this.textBox4.Name = "textBox4";
> this.textBox4.TabIndex = 5;
> this.textBox4.Text = "textBox4";
> //
> // textBox5
> //
> this.textBox5.Location = new System.Drawing.Point(8, 88);
> this.textBox5.Name = "textBox5";
> this.textBox5.TabIndex = 6;
> this.textBox5.Text = "textBox5";
> //
> // textBox6
> //
> this.textBox6.Location = new System.Drawing.Point(120, 88);
> this.textBox6.Name = "textBox6";
> this.textBox6.TabIndex = 7;
> this.textBox6.Text = "textBox6";
> //
> // Form2
> //
> this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
> this.ClientSize = new System.Drawing.Size(292, 266);
> this.Controls.Add(this.textBox6);
> this.Controls.Add(this.textBox5);
> this.Controls.Add(this.textBox4);
> this.Controls.Add(this.textBox3);
> this.Controls.Add(this.textBox2);
> this.Controls.Add(this.listBox1);
> this.Controls.Add(this.textBox1);
> this.Controls.Add(this.label1);
> this.Name = "Form2";
> this.Text = "Form2";
> this.ResumeLayout(false);
>
> }
> #endregion
> }
>}
>
>>
>
>run the form and go to file-> testForm, see how it flickers when the controls are created, now move the child form around, see how the controls are not moving smootly.
>
>remove the line:
>this.Opacity = 0;
>
>and try again, this fixes the problem, go figure....
>
>I'll never play with this opacity thigny again.
>
>HTH.
