CODEWITHSUNDEEP
c#.netwinformskrypton-toolkit
TheVillageIdiot
TheVillageIdiot

Reputation: 40537

Closing dialog form closes parent form

I have been dealing with strange problem. I am using KryptonForm in a project. I have a form (say form1) and I need to open another form on a button click from this form. Here is the code:

void btn_click(object sender, EventArgs e)
{
    Visible = false;
    ShowInTaskbar = false;

    var f = new Form2();
    f.ShowDialog();

    Visible = true;
    ShowInTaskbar = true;
}

The problem is that when the Form2 closes it closes the Form1 also. I have tried setting DialogResult = DialogResult.None from Form2 but of no avail. Please help me.

I am always using this technique and this thing has never happened.

Upvotes: 5

Views: 4439

Answers (3)

JesseChunn
JesseChunn

Reputation: 595

I know this is an old post, but I ran into this, and in my case the accepted answer (at the time I am writing this) is not helpful at all. The answer by @blind Skwirl led me to the culprit.

After 20 years of .Net programming (since it was introduced), I never noticed that BUTTONS have a "dialogresult" property. I always just set the forms "cancelbutton" and "acceptbutton" properties. What I found in my case was that (because I was doing a lot of copy-pasting of buttons), I had a bunch of buttons (not forms) that themselves had their "dialogresult" property set to "cancel", which meant that I would click a button on a dialog that would open another dialog, the "ok" button on the dialog had its result set to "cancel", and the button on the parent form ALSO had its result set to "cancel", so the dialog would close (with a result of cancel) and then the PARENT form would close with a result of cancel, confusing the heck out of me... so...

Just make sure all of your buttons have their dialogresult property set to NONE (or whatever the actual proper setting is that you want).

Bottom line, if a BUTTON (not the form) has its dialogresult property set to anything other than NONE, the form will close with that result when it is clicked (after any click event code has completed).

I hope that helps someone out there.

Upvotes: 5

blind Skwirl
blind Skwirl

Reputation: 351

Bugged me for days!! Found this: https://bytes.com/topic/net/answers/769433-c-showdialog-inside-showdialog-closing-both-return

The result was being passed down and I dont know why. But if after the .ShowDialog() I just put this.DialogResult = DialogResult.None, it will fix it. This shouldnt happen in the first place, but this fixes it, so I am not too bothered.

You can also try changing the dialogResult on the button itself to "None" or deleting the this.Btn1.DialogResult... from the designer which worked for some people.

https://social.msdn.microsoft.com/Forums/vstudio/en-US/543093ad-1860-4428-bae1-b0d4f112e04b/showdialog-closes-parent?forum=csharpgeneral

Upvotes: 1

Hans Passant
Hans Passant

Reputation: 942328

Yes, this code is troublesome. It goes wrong when the user closes the dialog. Windows must then find another window to give the focus to. There isn't any left in your app, your main window is invisible. It then picks a window of another app. Odds are good, for example, that this will be a window inside Visual Studio. A big one. Your main form now disappears behind it.

You need to make sure that your main window is visible again before the dialog closes. You can do so by subscribing to the dialog's FormClosing event handler. For example:

    private void button1_Click(object sender, EventArgs e) {
        using (var dlg = new Form2()) {
            dlg.StartPosition = FormStartPosition.Manual;
            dlg.Location = this.Location;
            dlg.FormClosing += (s, ea) => this.Show();    // <=== Here
            this.Hide();
            if (dlg.ShowDialog() == DialogResult.OK) {
                // etc...
            }
        }
    }

Upvotes: 7

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