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Displaying a panel in another windows form on button click c#

I'm working on a c# program and I want a panel to appear on a form when a button is clicked in another. So when the add button is clicked on form2 the panel requesting the details for this to be possible will be displayed on form 1.
I currently have a static method set up in form1 which can be accessed from form2 - however due to panel.Show() being non static it won't allow me to use this in the function.
In Form1 I have:
public static void showPanel()
{
panel.Show()
}
In my second form I have the following:
private void btn_add_Click(object sender, EventArgs e)
{
form1.showPanel();
this.Hide();
}
I have tested with just having the static function show a message box which works. Is it possible to do it the way I want or do I need to take a few steps back and try a different technique?

Are we talking about a new instance of the second form if so you can try to instantiate the new form using:
Form newForm = new YourFormName(potential parameters);
newForm.showPanel();
newForm.Show();
If you want to execute the form on an open form you can give the first form a reference(field with instance) of the second form. Or you can try using: Application.OpenForms. if you give it [1] it'll give you the second open form probably. You can also use .OfType to get the correct form in case your form order isn't always the same.

FormClosing with CloseReason = UserClosing doesn't work expectedly?

I have a main form, in the class of this form, I declare another form. This form lives with the main form until the main form is unloaded. There is a button on the main form, clicking this button will show the member form (I mentioned above). I want to prevent the member form from closing when user closes that form and I added the following FormClosing event handler for that form:
private void MemberForm_FormClosing(object sender, FormClosingEventArgs e) {
if(e.CloseReason == CloseReason.UserClosing){
e.Cancel = true;
Hide();
}
}
That works OK for that form. However if user closes the main form, this form is not closed, and it's hidden somewhere making my application seem to run silently. I want this form also to be closed. This is very simple by adding some FormClosed event handler for my main form to close the member form manually. Closing it manually is OK, but why do I have to do that? It seems that when user closes the main form, the FormClosing event of the member form is fired with a parameter FormClosingEventArgs passed in and the CloseReason is the same as the CloseReason of the main form (which is UserClosing). I don't understand this, I thought the CloseReason of the form is UserClosing only when user clicks on the X button, I thought the CloseReason for my member form is something like "MainFormClosing".
Is there some way to close the member form automatically as by default?
UPDATE
Here is the method showing the member form (showing it as a dialog):
private void ShowMemberForm_Click(object sender, EventArgs e){
memberForm.ShowDialog();
}
But I don't think this matters, because when I load my main form, even I don't need to click on the ShowMemberForm button, and try closing my main form first, it doesn't still close the member form.
Thanks!
UPDATE
There is something strange here, I've tried commenting out the line e.Cancel = true, or even all the FormClosing event handler and the problem is still there. This is so strange, it works OK before, I've just added the member form and this form relates to some Thread handling, but the thread starts only when a button on the member form is clicked. I didn't click that button.

What I have done in the past is set a flag when programatically closing
so in the MemberForm
private bool _ForceClose = false;
public void ForceClose()
{
_ForceClose = true;
this.Close();
}
private void MemberForm_FormClosing(object sender, FormClosingEventArgs e)
{
if(!_ForceClose)
{
e.Cancel = true;
Hide();
}
}
Then in your MainForm you can call
memberForm.ForceClose();
From within your MainForms FormClosing method or from your MainForms Dispose() or Deconstructor.
It's low tech, but it works. Im not sure if you should put _ForceClose = true in your MemberForm's Dispose method, i'm fairly certain when it gets there its already been closed BUT it couldn't really hurt.

Different form will not load

I'm using c# to make a mobile 6 application. I created another windows form in the project. This is the form that I would like to load first. This is what have tried:
MainMenu gameMenu = new MainMenu();
private void MainForm_Load(object sender, EventArgs e)
{
this.Hide();
gameMenu.ShowDialog();
.....
}
When I run this the emulator comes up but it just stays as the default windows screen. And I don't get any of my forms.

GameMenu's parent is MainForm, which is now hidden, so the Dialog isn't going to be visible. You need to adjust your logic to do one of the following:
show the GameMenu first (i.e. Application.Run(new GameMenu))
Don't hide MainForm
Use gameMenu.Show() instead of ShowDialog()

You may need to get rid of this.Hide() or use gameMenu.Show() instead of gameMenu.ShowDialog() or you may need to do both.
If you have to use gameMenu.Show() instead of gameMenu.ShowDialog(), you may also want to do the following:
Subscribe to MainForm's GotFocus event and call gameMenu.Show() again whenever the other form gains focus unintentionally. Set MainForm's Enabled property to false while the gameMenu is shown if you want to prevent any accidental interaction with the MainForm while the gameMenu is supposed to be shown.

Updating textbox on mainform with a variable on a child form that is launched from main form

I have a windows form app. The main form has a textbox, and a button to launch another form. When the other form is launched, both forms are on screen (but the launched form is modal). The child form has a textbox and button, and when the button is pressed, I want the textbox on the main form (the parent) to be updated with the value in the textbox on the child form.
How is this functionality achieved?

Ideally you want to keep both forms from being dependent on each other, this could be achieved with interfaces:
public interface IMainView
{
public void UpdateValue(string val);
}
public interface IChildView
{
public void Show(IMainView parent);
}
have your main form implement IMainView and the child implement IChildView, the parent calls child.show(this) and the child calls parent.UpdateValue(blah);
Hope this helps.

If the child form is closed when the button is clicked, you could put a public property which wraps the value of the textbox on the child form. Then the main form can read this property after calling ShowDialog.
If you want this to happen without closing the child form, you can create a function on the main form to change the textbox. Then the child form would call that function.

The best ways to achive this situation are clockWize's and Hans Passants's advices.
But what about that?
Write a property for your textbox at parent form, like this.
public string TextBoxText
{
get { return txtTextBox.Text;}
set { txtTextBox.Text = value;}
}
When you are opening the child form set the owner.
ChildForm f = new ChildForm();
f.Owner = this;
f.Show();
Create an event handler to child forms button click event.
public Button1_Click(object sender; EventArgs e)
{
ParentForm f = (ParentForm)this.Owner;
f.TextBoxText = txtChildTextBox.Text;
}
i didn't compile code; so may have errors :)
}

When a button is pressed to close the launched form, returning you to the main form- the launched form's text box is still in scope.
Closing a form is merely changing the object's state, not disposing of it. So in the button eventhandler that launches the form from the main form, the next line after launching your modal window, it can access the text from the object it launched as the textbox is a child of that form's object. Unless you're launching your modal window in another thread, which I wouldn't figure you are since it's modal, when it is closed, it should go to the next line in the buttons eventhandler that launched it.
your main form may have code something like this right now (haven't done winforms in a while so bear with me if I miss something):
public void Button1_Click(object sender, ClickEventArgs e)
{
SomeFormIWantToLaunch launchForm = new SomeFormIWantToLaunch();
launchForm.ShowDialog(this);
}
You need to just add after launchForm.ShowDialog(this); something like:
this.SomeTextBox.Text = launchForm.ATextBox.Text;

WinForms programming - Modal and Non-Modal forms problem

I have a problem with modality of the forms under C#.NET. Let's say I have main form #0 (see the image below). This form represents main application form, where user can perform various operations. However, from time to time, there is a need to open additional non-modal form to perform additional main application functionality supporting tasks. Let's say this is form #1 in the image. On this #1 form there might be opened few additional modal forms on top of each other (#2 form in the image), and at the end, there is a progress dialog showing a long operation progress and status, which might take from few minutes up to few hours. The problem is that the main form #0 is not responsive until you close all modal forms (#2 in the image). I need that the main form #0 would be operational in this situation. However, if you open a non-modal form in form #2, you can operate with both modal #2 form and newly created non modal form. I need the same behavior between the main form #0 and form #1 with all its child forms. Is it possible? Or am I doing something wrong? Maybe there is some kind of workaround, I really would not like to change all ShowDialog calls to Show...
Image http://img225.imageshack.us/img225/1075/modalnonmodalproblem.png

Modal forms do exactly what "modal" means, they disable all other windows in the app. That's rather important, your program is in a somewhat perilous state. You've got a chunk of code that is waiting for the dialog to close. Really Bad Things could happen if those other windows were not disabled. Like the user could start the modal dialog again, now your code is nested twice. Or she could close the owner window of the dialog, now it suddenly disappears.
These are the exact kind of problems you'd run into if you call Application.DoEvents() inside a loop. Which is one way to get a form to behave modal without disabling other windows. For example:
Form2 mDialog;
private void button1_Click(object sender, EventArgs e) {
mDialog = new Form2();
mDialog.FormClosed += (o, ea) => mDialog = null;
mDialog.Show(this);
while (mDialog != null) Application.DoEvents();
}
This is dangerous.
It is certainly best to use modal forms the way they were designed to stay out of trouble. If you don't want a modal form then simply don't make it modal, use the Show() method. Subscribe to its FormClosing event to know that it is about to close:
private void button1_Click(object sender, EventArgs e) {
var frm = new Form2();
frm.FormClosing += new FormClosingEventHandler(frm_FormClosing);
frm.Show();
}
void frm_FormClosing(object sender, FormClosingEventArgs e) {
var frm = sender as Form2;
// Do something with <frm>
//...
}

The first thing that comes to mind would be something like this. You could disable form 1 when you launch form 2 and then have form 1 handle the closed event of the second form to re-enable itself. You would NOT open modal 2 using show dialog.
Now keep in mind, from a user perspective this is going to be quite cumbersome, you might look at doing a MDI application to get all windows inside of a single container.

Your main form will not be responsive until any modal dialogs that are in the same process space are closed. There is not work around for that.

It looks to me like you could use an MDI application setting the Form #0 IsMdiContainer property to true.
Then, you could do something alike:
public partial class Form0 {
public Form0 {
InitializeComponent();
this.IsMdiContainer = true; // This will allow the Form #0 to be responsive while other forms are opened.
}
private void button1_Click(object sender, EventArgs e) {
Form1 newForm1 = new Form1();
newForm1.Parent = this;
newForm1.Show();
}
}
Using the ShowDialog() as you stated in your question will make all of the forms Modal = true.
By definition, a modal form is:
When a form is displayed modally, no input (keyboard or mouse click) can occur except to objects on the modal form. The program must hide or close a modal form (usually in response to some user action) before input to another form can occur. Forms that are displayed modally are typically used as dialog boxes in an application.
You can use this property [(Modal)] to determine whether a form that you have obtained from a method or property has been displayed modally.
So, a modal form shall be used only when you require immediate assistance/interaction from the user. Using modal forms otherwise makes believe that you're perhaps running into a wrong direction.
If you do not want your main form to be an MDI container, then perhaps using multithreading is one solution through a simple BackgroundWorker class is the key to what you want to achieve. Thus, it looks to me like a design smell...
What is it you want to do, apart of making your main form responsive, etc.
What is it you have to do?
Explaining what you have to do, we might be able to guide you altogether into the right, or at least perhaps better, direction.

Actually the answer is very simple. Try
newForm.showDialog();
This will open a new form, while the parent one is inaccessible.