Question of the Week presents answers to key questions posed by the developer community. The intent is to pass this important, but not always easy-to-find, information on to Java^TM Developer Connection^SM (JDC) members. The questions are selected from the JDC newsgroups generally because: they are frequently asked, they are significant or timely, or their answers are not easily accessible.

Note: If you have a question to which you need an answer, try the JDC newsgroups. You can read through the existing newsgroups, or with your free JDC membership, you can post new messages or threads.

Question of the Week Archive

Topic:   How can I bring up an iconified JFrame?

Question:  Will someone tell me how to bring up a JFrame from the task bar without actually clicking on it? In my application, when a user tries to open up a window, my application checks for a window open already. If one is open, it will bring it up to the front.

Answer:

If you are using JDK^TM 1.2.x you can use the Frame class's setState() method passing it 'Frame.NORMAL' to unminimize a frame. See attached sample working code that unminimizes a JFrame two seconds after it's been minimized.

import java.awt.event.*; 
import java.awt.*; 
import javax.swing.*; 

public class Unminimize { 
    
  public static void main(String args[]) { 
   new UnminimizeFrame(); 
    } 
} 

class UnminimizeFrame extends JFrame { 

    UnminimizeFrame() { 
	super(); 
	
	// Components should be added to 
	//the container's content pane 
	Container cp = getContentPane(); 

	/* Add the window listener */ 
	addWindowListener(new WindowAdapter() { 
	    public void windowClosing(
	                     WindowEvent evt) { 
		dispose(); 
		System.exit(0);
	    } 
	    public void windowIconified(
	                     WindowEvent evt) { 
		try {
		    Thread.sleep(2000);
		} 
		catch(InterruptedException ie){} 
		setState(Frame.NORMAL);
	    }
	}); 

	/* Size the frame */ 
	setSize(200,200); 

	/* Center the frame */ 
	Dimension screenDim = 
	 Toolkit.getDefaultToolkit(
	                    ).getScreenSize(); 
	Rectangle frameDim = getBounds(); 

	setLocation((screenDim.width - 
	  frameDim.width) / 2,(screenDim.height - 
	                   frameDim.height) / 2); 
	
	/* Show the frame */ 
	setVisible(true); 
    } 
} 

Many thanks to JDC member paternostro for contributing to this answer.