Edit JPanel Text During Runtime...from another class

[bdn1404]

I am very new to Java and am having trouble changing text at runtime in a JLabel. My main class is set up to handle the computation and displays the UI frame when necessary. I am reading in data real-time so i need to be able to constantly change the label in my frame as the data changes.

I have been testing to see if I could make the runtime changes by putting the code directly into the UIFrame's main. I created the label using the Netbeans design editor and then used this code:

Code:

JLabel jLabel1 = null;
jLabel1.setText("text");

which gave me no errors, but had no effect on the label. How do I link my code-created instance with the Netbeans-created label?

Then, if I can get that to work, how do I access that same label from my (seperate) Main class?

Thanks

[elizabeth]

Write this

Code:

JLabel jLabel1= new JLabel("text");

instead of

Code:

JLabel jLabel1 = null;
jLabel1.setText("text");

[bdn1404]

I have tried that as well. It seems that my frame is not changing anything at runtime. I have tried repainting it, but nothing will change unless I get an event involved.

When I used a button click event as a test, I was able to use the same jPanel1 that I created in Netbeans, because of the nonstatic context. However, when I try to do the same in a main, I have to create an instance which isn't changing.

[mary]

please send me the complete code to test it in my machine

[rhobincu]

Quote:

Originally Posted by bdn1404

Code:

JLabel jLabel1 = null;
jLabel1.setText("text");

Check the console. This will most surely generate a NullPointerException.

[cruxblack]

Maybe im wrong, but this is what i get in mind

Quote:

Originally Posted by bdn1404

need to be able to constantly change the label in my frame as the data changes.

Why don't u use a function with a String variable parameter to replace "text" in that class ur working on so that it that can be called from ur main class, maybe like this

Code:

JLabel jLabel1 = new JLabel(initialValue);
setLabel(String input)
{
	jLabel1= new JLabel(input);
}

And yes, u better post the code