[Mono-winforms-list] Bug in System.Windows.Forms.Control:get_ContainsFocus ()?
Hi,
I'm porting an application from MS. NET to Mono and I have encountered
the following, maybe it's a bug or maybe it's just bad coding :-)
The attached code sends Mono into a loop until it eventually crashes
with a segmentation error (When button1 is clicked). Should I report
this as a bug or is this just dodgy code to override the get_Focused
method like this?
Compile with:
mcs base.cs -r:System.Windows.Forms -r:System.Data -r:System.Drawing
run mono base.exe
Click on button1.
Code and trace attached.
Thanks,
Paddy
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
namespace WindowsApplication4
{
/// summary
/// Summary description for Form1.
/// /summary
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Button button1;
private System.Windows.Forms.Button button2;
/// summary
/// Required designer variable.
/// /summary
private System.ComponentModel.Container components = null;
public Form1()
{
//
// 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.button1 = new System.Windows.Forms.Button();
this.button2 = new testbutton();
this.SuspendLayout();
//
// button1
//
this.button1.Location = new System.Drawing.Point(96, 32);
this.button1.Name = button1;
this.button1.TabIndex = 0;
this.button1.Text = button1;
this.button1.Click += new System.EventHandler(this.button1_Click);
//
// button2
//
this.button2.Location = new System.Drawing.Point(96, 80);
this.button2.Name = button2;
this.button2.TabIndex = 1;
this.button2.Text = button2;
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(292, 262);
this.Controls.Add(this.button2);
this.Controls.Add(this.button1);
this.Name = Form1;
this.Text = Form1;
this.ResumeLayout(false);
}
#endregion
/// summary
/// The main entry point for the application.
/// /summary
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
private void button1_Click(object sender, System.EventArgs e)
{
Console.Write(button2.Focused);
}
}
public class testbutton : System.Windows.Forms.Button
{
public testbutton()
{
}
public override bool Focused
{
get
{
return base.ContainsFocus;
}
}
}
}
. . . . . . . . . . . . . . . . . . . . . . . . . . ENTER:
System.Windows.Forms.Button:OnClick
(System.EventArgs)(this:0x5c2a8[System.Windows.Forms.Button WindowsForm.exe],
[System.EventArgs:0x2ff68], )
. . . . . . . . . . . . . . . . . . . . . . . . . . . ENTER:
System.Windows.Forms.Control:OnClick
(System.EventArgs)(this:0x5c2a8[System.Windows.Forms.Button WindowsForm.exe],
[System.EventArgs:0x2ff68], )
. . . . . . . . . . . . . . . . . . . . . . . . . . . . ENTER: (wrapper
delegate-invoke) System.MulticastDelegate:invoke_void_object_EventArgs
(object,System.EventArgs)(this:0x4c5a0[System.EventHandler WindowsForm.exe],
[System.Windows.Forms.Button:0x5c2a8], [System.EventArgs:0x2ff68], )
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . ENTER:
WindowsApplication4.Form1:button1_Click
(object,System.EventArgs)(this:0x3[WindowsApplication4.Form1
WindowsForm.exe], [System.Windows.Forms.Button:0x5c2a8],
[System.EventArgs:0x2ff68], )
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ENTER:
WindowsApplication4.testbutton:get_Focused
()(this:0x5c000[WindowsApplication4.testbutton WindowsForm.exe], )
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ENTER:
System.Windows.Forms.Control:get_ContainsFocus
()(this:0x5c000[WindowsApplication4.testbutton WindowsForm.exe], )
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ENTER:
WindowsApplication4.testbutton:get_Focused
()(this:0x5c000[WindowsApplication4.testbutton WindowsForm.exe], )
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ENTER:
System.Windows.Forms.Control:get_ContainsFocus
()(this:0x5c000[WindowsApplication4.testbutton WindowsForm.exe], )
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ENTER:
WindowsApplication4.testbutton:get_Focused
()(this:0x5c000[WindowsApplication4.testbutton WindowsForm.exe], )
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Re: [Mono-winforms-list] Bug in System.Windows.Forms.Control:get_ContainsFocus ()?
Hi,
So do you think it could be a bug with resolving the base class? It
seems from the trace that it is going into a continuous loop, like it is
calling ContainsFocus on itself.
To be honest, all I saw was the segfault rather than the tonnes of
output. The baseclass seems to be working fine as well
I did the following to your code and if you run it, you'll see that the
baseclass is fine
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
namespace WinApp4
{
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Button button1;
private System.Windows.Forms.Button button2;
private System.ComponentModel.Container components = null;
public Form1()
{
InitializeComponent();
}
protected override void Dispose(bool disposing)
{
if (disposing)
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose(disposing);
}
private void InitializeComponent()
{
this.button1 = new System.Windows.Forms.Button();
this.button2 = new System.Windows.Forms.Button();
this.SuspendLayout();
this.button1.Location = new System.Drawing.Point(96, 32);
this.button1.Name = button1;
this.button1.TabIndex = 0;
this.button1.Text = button1;
this.button1.Click += new System.EventHandler(this.button1_Click);
this.button2.Location = new System.Drawing.Point(96, 80);
this.button2.Name = button2;
this.button2.TabIndex = 1;
this.button2.Text = button2;
this.button2.Click += new System.EventHandler(this.button2_Click);
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(292, 262);
this.Controls.Add(this.button2);
this.Controls.Add(this.button1);
this.Name = Form1;
this.Text = Form1;
this.ResumeLayout(false);
}
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
private void button1_Click(object sender, System.EventArgs e)
{
Console.Write(base.ContainsFocus);
}
private void button2_Click(object sender, System.EventArgs e)
{
Console.WriteLine(base.ContainsFocus);
}
}
}
The output (at least on my box) is
True (button 1 pressed - no return feed)
TrueTrue (button 2 pressed)
From the looks of the original code, you've created the second button,
but never properly instantated it (it is declared as private swf.button
button2 at the start, but never created using this.button2 = new
swf.button()). That (to me) is the most likely candidate for the
breakage.
TTFN
Paul
--
Logic, my dear Zoe, is merely the ability to be wrong with authority -
Dr Who
___
Mono-winforms-list maillist - Mono-winforms-list@lists.ximian.com
http://lists.ximian.com/mailman/listinfo/mono-winforms-list
Re: [Mono-winforms-list] Bug in System.Windows.Forms.Control:get_ContainsFocus ()?
How about this code, I'm pretty sure that it instantiates button2
correctly now but still gives the segmentation error.
I have declared the button with:
private testbutton button2;
and instantiated it with:
this.button2 = new testbutton();
Thanks for the help,
Paddy
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
namespace WindowsApplication4
{
/// summary
/// Summary description for Form1.
/// /summary
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Button button1;
private testbutton button2;
/// summary
/// Required designer variable.
/// /summary
private System.ComponentModel.Container components = null;
public Form1()
{
//
// 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.button1 = new System.Windows.Forms.Button();
this.button2 = new testbutton();
this.SuspendLayout();
//
// button1
//
this.button1.Location = new System.Drawing.Point(96, 32);
this.button1.Name = button1;
this.button1.TabIndex = 0;
this.button1.Text = button1;
this.button1.Click += new
System.EventHandler(this.button1_Click);
//
// button2
//
this.button2.Location = new System.Drawing.Point(96, 80);
this.button2.Name = button2;
this.button2.TabIndex = 1;
this.button2.Text = button2;
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(292, 262);
this.Controls.Add(this.button2);
this.Controls.Add(this.button1);
this.Name = Form1;
this.Text = Form1;
this.ResumeLayout(false);
}
#endregion
/// summary
/// The main entry point for the application.
/// /summary
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
private void button1_Click(object sender, System.EventArgs e)
{
Console.Write(button2.Focused);
}
}
public class testbutton : System.Windows.Forms.Button
{
public testbutton()
{
}
public override bool Focused
{
get
{
return base.ContainsFocus;
}
}
}
}
Hi,
So do you think it could be a bug with resolving the base class? It
seems from the trace that it is going into a continuous loop, like it is
calling ContainsFocus on itself.
To be honest, all I saw was the segfault rather than the tonnes of
output. The baseclass seems to be working fine as well
I did the following to your code and if you run it, you'll see that the
baseclass is fine
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
namespace WinApp4
{
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Button button1;
private System.Windows.Forms.Button button2;
private System.ComponentModel.Container components = null;
public Form1()
{
InitializeComponent();
}
protected override void Dispose(bool disposing)
{
if (disposing)
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose(disposing);
}
private void InitializeComponent()
{
this.button1 = new System.Windows.Forms.Button();
this.button2 = new System.Windows.Forms.Button();
this.SuspendLayout();
this.button1.Location = new System.Drawing.Point(96, 32);
this.button1.Name = button1;
this.button1.TabIndex = 0;
this.button1.Text = button1;
this.button1.Click += new
Re: [Mono-winforms-list] Bug in System.Windows.Forms.Control:get_ContainsFocus ()?
Hi Paddy,
Why do you return base.ContainFocus instead of base.Focused from your
overriden Focused? That way you are introducing infinite recursion as
Control.ContainsFocus calls Control.Focused, that in your case is
overriden.
In truth, unless this is just some small code to show the problem, I
don't see any need to override Focused... Even more to change its
semantics.
Anyway if that code works in MS.NET, we should not rely on Focused to
determine partially the value of ContainsFocus (ContainsFocus also
checks children if the Control per se isn't with focus). Test it in
MS.NEt and if it works OK, please fill a bug for MWF, thanks.
:|
On 6/21/06, Paddy Joy [EMAIL PROTECTED] wrote:
How about this code, I'm pretty sure that it instantiates button2
correctly now but still gives the segmentation error.
I have declared the button with:
private testbutton button2;
and instantiated it with:
this.button2 = new testbutton();
Thanks for the help,
Paddy
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
namespace WindowsApplication4
{
/// summary
/// Summary description for Form1.
/// /summary
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Button button1;
private testbutton button2;
/// summary
/// Required designer variable.
/// /summary
private System.ComponentModel.Container components = null;
public Form1()
{
//
// 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.button1 = new System.Windows.Forms.Button();
this.button2 = new testbutton();
this.SuspendLayout();
//
// button1
//
this.button1.Location = new System.Drawing.Point(96, 32);
this.button1.Name = button1;
this.button1.TabIndex = 0;
this.button1.Text = button1;
this.button1.Click += new
System.EventHandler(this.button1_Click);
//
// button2
//
this.button2.Location = new System.Drawing.Point(96, 80);
this.button2.Name = button2;
this.button2.TabIndex = 1;
this.button2.Text = button2;
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(292, 262);
this.Controls.Add(this.button2);
this.Controls.Add(this.button1);
this.Name = Form1;
this.Text = Form1;
this.ResumeLayout(false);
}
#endregion
/// summary
/// The main entry point for the application.
/// /summary
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
private void button1_Click(object sender, System.EventArgs e)
{
Console.Write(button2.Focused);
}
}
public class testbutton : System.Windows.Forms.Button
{
public testbutton()
{
}
public override bool Focused
{
get
{
return base.ContainsFocus;
}
}
}
}
Hi,
So do you think it could be a bug with resolving the base class? It
seems from the trace that it is going into a continuous loop, like it is
calling ContainsFocus on itself.
To be honest, all I saw was the segfault rather than the tonnes of
output. The baseclass seems to be working fine as well
I did the following to your code and if you run it, you'll see that the
baseclass is fine
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
namespace WinApp4
{
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Button button1;
private
Re: [Mono-winforms-list] Bug in System.Windows.Forms.Control:get_ContainsFocus ()?
Hi Rafael,
Yes this problem exists in a much larger application involving lots of
custom controls, I have just created this code to demonstrate the
problem as simply as possible.
I have tested the code in MS .NET and it works ok and returns False to
the console as expected so I have logged a bug
http://bugzilla.ximian.com/show_bug.cgi?id=78685
Thanks for your help,
Paddy
Rafael Teixeira wrote:
Hi Paddy,
Why do you return base.ContainFocus instead of base.Focused from your
overriden Focused? That way you are introducing infinite recursion as
Control.ContainsFocus calls Control.Focused, that in your case is
overriden.
In truth, unless this is just some small code to show the problem, I
don't see any need to override Focused... Even more to change its
semantics.
Anyway if that code works in MS.NET, we should not rely on Focused to
determine partially the value of ContainsFocus (ContainsFocus also
checks children if the Control per se isn't with focus). Test it in
MS.NEt and if it works OK, please fill a bug for MWF, thanks.
:|
On 6/21/06, Paddy Joy [EMAIL PROTECTED] wrote:
How about this code, I'm pretty sure that it instantiates button2
correctly now but still gives the segmentation error.
I have declared the button with:
private testbutton button2;
and instantiated it with:
this.button2 = new testbutton();
Thanks for the help,
Paddy
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
namespace WindowsApplication4
{
/// summary
/// Summary description for Form1.
/// /summary
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Button button1;
private testbutton button2;
/// summary
/// Required designer variable.
/// /summary
private System.ComponentModel.Container components = null;
public Form1()
{
//
// 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.button1 = new System.Windows.Forms.Button();
this.button2 = new testbutton();
this.SuspendLayout();
//
// button1
//
this.button1.Location = new System.Drawing.Point(96, 32);
this.button1.Name = button1;
this.button1.TabIndex = 0;
this.button1.Text = button1;
this.button1.Click += new
System.EventHandler(this.button1_Click);
//
// button2
//
this.button2.Location = new System.Drawing.Point(96, 80);
this.button2.Name = button2;
this.button2.TabIndex = 1;
this.button2.Text = button2;
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(292, 262);
this.Controls.Add(this.button2);
this.Controls.Add(this.button1);
this.Name = Form1;
this.Text = Form1;
this.ResumeLayout(false);
}
#endregion
/// summary
/// The main entry point for the application.
/// /summary
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
private void button1_Click(object sender, System.EventArgs e)
{
Console.Write(button2.Focused);
}
}
public class testbutton : System.Windows.Forms.Button
{
public testbutton()
{
}
public override bool Focused
{
get
{
return base.ContainsFocus;
}
}
}
}
Hi,
So do you think it could be a bug with resolving the base class? It
seems from the trace that it is going into a continuous loop, like
it is
calling ContainsFocus on itself.
To be honest, all I saw was the segfault rather than the tonnes of
output. The baseclass
