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Problem with label text

Hey, i'm having this problem with one of my labels.
I'm attempting to modify a label on a separate class, when i debug it, it shows that the text value has changed, but the label itself doesn't. and yes i have tried the Refresh() method.

Alca7raz Thursday, April 19, 2007 7:01 AM

Do it like this to handle all eventualities:

private Form2 formRef;

private void nowBtn_Click(object sender, EventArgs e) {
if (formRef != null) {
formRef = new Form2(this);
formRef.FormClosed += Form2Closed;
formRef.Show();
}
}
private void Form2Closed(object sender, FormClosedEventArgs e) {
formRef = null;
}
private void updateLabelText() {
if (formRef != null) formRef.updateText("Nobugz waz here");
}

Everything gets to be a lot easier if you use an event. You can now how more than one instance of Form2 and don't have to worry about cleanup:

In Form1:
public delegate void NewLabelTextEventHandler(object sender, string text);
public event NewLabelTextEventHandler NewLabelText;

private void nowBtn_Click(object sender, EventArgs e) {
Form2 f2 = new Form2(this);
f2.Show();
}
private void updateLabelText() {
if (NewLabelText != null) NewLabelText.Invoke(this, "Nobugz waz here");
}

In Form2:
public partial class Form2 : Form {
public Form2(Form1 mainForm) {
InitializeComponent();
mainForm.NewLabelText += updateText;
}
private void updateText(object sender, string text) {
label1.Text = text;
}
}

nobugz Friday, April 20, 2007 7:09 AM

Hi,

How r u accessing the lable of one form in another class?

It should work ,if the reference of parent form of label is passed to the second class.

Thanks,

Ch.T.Gopi Kumar.

TilakGopi Thursday, April 19, 2007 7:15 AM

Here is an example of how im doing it:

Code Snippet

Form1
{
Form2 formRef = new Form2(this);
formRef.updateText(STRING VARIABLE HERE);
}

Form2(Form1 mainForm)
{
internal void updateText(string RecievedText)
{
Label.Text = RecievedText;
Label.Refresh();
}
}

something along those lines, i dont have my code in front of me at the moment

Alca7raz Thursday, April 19, 2007 7:01 PM

Your "formRef" is wrong. You are creating a new instance of the Form2 class instead of using the existing instance. Since you never call formRef.Show(), that new instance with the updated label text is not visible.

nobugz Thursday, April 19, 2007 7:14 PM

Ok, ill try to explain a bit more about the program and the problem. the Form2 class has an invisble form covering all of the screen with a label on it. I am showing the form, and the label does show up. the problem i am having is that even with using the Refresh() method, the label isnt changing.Heres a better example of my code:

public partial class Form1 : Form
{
private void nowBtn_Click(object sender, EventArgs e)
{
Form2 formRef = new Form2(this);
//some code
formRef.Show();
}
private void updateLabelText() //called from a Timer Tick Event
{
//some code
formRef.updateText(timerText);
}
}

public partial class Form2 : Form
{
private Form1 formRef = null;
public Form2(Form1 mainForm)
{
//
// The InitializeComponent() call is required for Windows Forms designer support. //
this.formRef = mainForm;
InitializeComponent();
//
// TODO: Add constructor code after the InitializeComponent() call.
//
}
internal void updateText(string RecievedText)
{
timerLabel.Text = RecievedText;
timerLabel.Refresh();
}
}

How would you have me set up my "formRef"?

Alca7raz Friday, April 20, 2007 4:29 AM

public partial class Form1 : Form
{
private Form2 formRef;

private void nowBtn_Click(object sender, EventArgs e)
{
formRef = new Form2(this);
//some code
formRef.Show();
}
private void updateLabelText() //called from a Timer Tick Event
{
//some code
formRef.updateText(timerText);
}
}

public partial class Form2 : Form
{
private Form1 formRef = null;
public Form2(Form1 mainForm)
{
//
// The InitializeComponent() call is required for Windows Forms designer support. //
this.formRef = mainForm;
InitializeComponent();
//
// TODO: Add constructor code after the InitializeComponent() call.
//
}
internal void updateText(string RecievedText)
{
timerLabel.Text = RecievedText;
timerLabel.Refresh();
}
}