Can't bring form to front

  • Thread starter Thread starter Anders Thomsen
  • Start date Start date
A

Anders Thomsen

Hi ng,

I have a problem when trying to focus certain forms.

My application consists of several forms, at first form1 is shown. Clicking
a button here will close form1 and show form2. When form2 i showing, I try
to open the File manager in PPC. From here, I can navigate to my project
folder and open my application by clicking on the .exe. This opens up the
app where I left it, showing form2 - as suspected.

Then I click a button on form2 which closes form2 and create a new instance
of Form1 (the first instance was disposed and it's reference set to null).
On this new instance i've tried to call BringtoFront(), Focus(), Show and
Visible = true, but I simply can't get the form to show. Instead, the file
manager is shown - which is okay, since it's the next form in the Z-order
after form2. But after creating Form1 and calling BringToFront etc. I
believe that form1 should be put on top.

How can I activate form1?

Thanks in advantage,
 
Hi, there

I am wondering when you click the button on form2, it closes form2 itself
AND
create a new instance of form1, is that right?
If correct, the the sequence of statement is important, for example:
<in form2 instance>
this.Close(); // When it close, who will keep the reference of frm?
form1 frm=new form1();
frm.Show();

Another exampler:
<in form2 instance>
form1 frm=new form1();
frm.Show();
this.Close(); // When it close, it dispose everything in form2, including
frm.

The result of above will cause frm instance disappear, as you've seen.

----------------------------------------------------------------------------
--
You may try the following way.
<in form1 instance>
private void Button1_Click(
form2 frm2=new form2(this); // pass the handle of form1 to form2
frm2.Show();
this.Hide();
<in form2 instance>
private form1 f=null;
public form2(form1 frm)
{
f=frm; // form2 will take the handle of form1 instance
}

private void Button1_Click(object sender, EventArgs e)
{
f.Show();
this.Hide(); // or this.Close();
// then it will back to the original form1, instead of a new instance.
}
 
Actually, it's not form2 who creates form1, but some underlying handlers.
The form1 IS there, as it is focused when I minimize the filemanager.
 
To set focus on a form I had to P/Invoke to get it to work properly. Try
this code:

[DllImport("coredll",EntryPoint="FindWindow")]
public static extern IntPtr FindWindow(string lpClassName,string
lpWindowName);
[DllImport("coredll",EntryPoint="SetForegroundWindow")]
public static extern bool SetForegroundWindow(IntPtr hWnd);

IntPtr hWnd = FindWindow(null,form1.Text);
if(!hWnd.Equals(IntPtr.Zero))
SetForegroundWindow(hWnd);

HTH
Mark Arteaga
www.clearknowledge.com
 
Okay, thanks.

Do you know if there's another way to get the handle of the form - many of
my forms has
the same title.

-and thanks again : )

Mark Arteaga said:
To set focus on a form I had to P/Invoke to get it to work properly. Try
this code:

[DllImport("coredll",EntryPoint="FindWindow")]
public static extern IntPtr FindWindow(string lpClassName,string
lpWindowName);
[DllImport("coredll",EntryPoint="SetForegroundWindow")]
public static extern bool SetForegroundWindow(IntPtr hWnd);

IntPtr hWnd = FindWindow(null,form1.Text);
if(!hWnd.Equals(IntPtr.Zero))
SetForegroundWindow(hWnd);

HTH
Mark Arteaga
www.clearknowledge.com

Anders Thomsen said:
Actually, it's not form2 who creates form1, but some underlying handlers.
The form1 IS there, as it is focused when I minimize the filemanager.
Click to expand...
Click to expand...
 
yup....on the form set Capture=ture then p/invoke get capture. this will
return the handle.

[DllImport("coredll.dll", EntryPoint="GetCapture", SetLastError=true)]
private static extern IntPtr GetCapture();

HTH
Mark.
Anders Thomsen said:
Okay, thanks.

Do you know if there's another way to get the handle of the form - many of
my forms has
the same title.

-and thanks again : )

Mark Arteaga said:
To set focus on a form I had to P/Invoke to get it to work properly. Try
this code:

[DllImport("coredll",EntryPoint="FindWindow")]
public static extern IntPtr FindWindow(string lpClassName,string
lpWindowName);
[DllImport("coredll",EntryPoint="SetForegroundWindow")]
public static extern bool SetForegroundWindow(IntPtr hWnd);

IntPtr hWnd = FindWindow(null,form1.Text);
if(!hWnd.Equals(IntPtr.Zero))
SetForegroundWindow(hWnd);

HTH
Mark Arteaga
www.clearknowledge.com

Anders Thomsen said:
Actually, it's not form2 who creates form1, but some underlying handlers.
The form1 IS there, as it is focused when I minimize the filemanager.



Hi, there

I am wondering when you click the button on form2, it closes form2 itself
AND
create a new instance of form1, is that right?
If correct, the the sequence of statement is important, for example:
<in form2 instance>
this.Close(); // When it close, who will keep the reference of frm?
form1 frm=new form1();
frm.Show();

Another exampler:
<in form2 instance>
form1 frm=new form1();
frm.Show();
this.Close(); // When it close, it dispose everything in form2,
including
frm.

The result of above will cause frm instance disappear, as you've seen.
Click to expand...
Click to expand...
Click to expand...
 
When I try to deploy my project with VS.NET on the device (PocketPC 2002) OR
on the emulator TOO !,
VS.NET gives me this error while copying the files:
"Error: Cannot establish a connection. Be sure the device is physically
connected to the development computer."

therefore I can't debug, well I could copy the application and see what
happen....
but it would be better if I could use the debugger !
 
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