JTextArea and its cut/copy/paste Actions

> > I don't believe that I have to carouse this array and look for a nested

> > DefaultEditorToolkit.CopyAction object

>

> 1) Use the InputMap and ActionMap to get the Action directly> KeyStroke controlC = KeyStroke.getKeyStroke("control C");

> Action copy = textArea.getActionMap().get(textArea.getInputMap().get(controlC));

> 2) Create a new Action:> Action copy = new DefaultEditorKit.CopyAction();

While I do understand option 1), what about option 2) then? How does

the action know about which JTextArea needs its contents to be copied?

That's one part of the docs that left me puzzled, so you hit my problem

right on its head.

On top of that: thanks a bunch; much appreciated. You answer about

every question here don't you? ;-)

kind regards,

Jos (< Swing nono)

JosAHa at 2007-7-15 5:13:42 >

> How does

> the action know about which JTextArea needs its

> contents to be copied?

>

If I still remember correctly, the action acts on any text component that currently has focus.

The only disadventage of #2 is that if you need to disable/enable the action, you'll have to make sure to call setEnabled() on both instances.

dberanskya at 2007-7-15 5:13:42 >

> > what about option 2) then? How does the action know

> about which JTextArea needs its contents to be copied?

>

> The editor kit actions extend TextAction which has a method

> getFocusedComponent() which tracks the last JTextComponent

> that has (had) focus, so it even works when you click on an Action

> that has been added to a toolbar or menu item.

If that is true (and I believe you) that implies that I don't understand

focus traversal either. Suppose two nonmodal dialogs, both with a

text component in it and both with a 'copy' button that both have that

same Action object. Suppose I click the left text component (so it has

the focus now) and then click the right 'copy' button in the other dialog.

I really am a Swing nono ...

kind regards,

Jos

JosAHa at 2007-7-15 5:13:42 >

Hi

I got simple problem. I want to select Image through JFileChooser and pick that path of image and put the image to panel. I wrote this code for same I am geting path in all the methods, But not image could you plz help me

import java.awt.Graphics;

import java.awt.Image;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.IOException;

import javax.imageio.ImageIO;

import javax.swing.JButton;

import javax.swing.JFileChooser;

import javax.swing.JFrame;

import javax.swing.JMenu;

import javax.swing.JMenuBar;

import javax.swing.JMenuItem;

import javax.swing.JPanel;

public class MainClass extends JPanel implements ActionListener{

public JMenuBar manuBar=new JMenuBar();

public JMenu menu=new JMenu("File");

public JMenuItem menuItem=new JMenuItem("New");

public JFrame frame = new JFrame();

public static File selPath;

public JFileChooser ch=new JFileChooser();

public Graphics g;

public void paint(Graphics g,File selPath) {

System.out.println("In Graphics := "+selPath);

g.drawImage(createImage(selPath), 40,40,this);

}

public void launchFrame(){

frame.setJMenuBar(manuBar);

manuBar.add(menu);

menu.add(menuItem);

frame.getContentPane().add(new MainClass());

menuItem.addActionListener(this);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.setLocation(350,200);

frame.setSize(300, 300);

frame.setVisible(true);

}

public static void main(String[] args) {

MainClass gui=new MainClass();

gui.launchFrame();

}

private Image createImage(File selPath){

BufferedImage bufferedImage = new BufferedImage(200,200,BufferedImage.TYPE_INT_RGB);

Graphics g = bufferedImage.getGraphics();

try {

System.out.println("In Try Catch :="+selPath);

bufferedImage=ImageIO.read(new FileInputStream(selPath));

//bufferedImage=ImageIO.read(new FileInputStream("C:/Documents and Settings/Santosh/My Documents/My Pictures/house.gif"));

} catch (FileNotFoundException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

g.drawString("My Program", 40,40);

return bufferedImage;

}

public File addFileChooser(){

ch=new JFileChooser();

int status = ch.showSaveDialog(null);

if (status == JFileChooser.APPROVE_OPTION) {

File selectedFile =ch.getSelectedFile();

selPath=ch.getSelectedFile();

selPath.getParent();

System.out.println("My path:-"+selPath);

System.out.println("Selected:-"

+ selectedFile.getParent()

+ " "

+ selectedFile.getName());

}

ch.setSize(200,200);

ch.setVisible(true);

System.out.println("Path At end:-"+selPath);

//imageBackGround(selPath.getAbsolutePath());

createImage(selPath);

return selPath;

}

public void actionPerformed(ActionEvent arg0) {

String command=arg0.getActionCommand();

if( command.equals("New") ){

System.out.println("In Side Action Listener");

addFileChooser();

frame.setVisible(true);

}

}

}

With Regards

Santosh Pathak

san4javaa at 2007-7-15 5:13:42 >

> > Suppose I click the left text component (so it has

> > the focus now) and then click the right 'copy' button

> > in the other dialog.

>

> Then the action will be performed on the left component; the system

> isn't foolproof. Of greater concern, I think, is what happens when you

> have a textfield in the same window as the textarea--for instance, if

> you decide to put a "quick search" field in the toolbar. Then you would

> have to actively manage the focus, and maybe have problems anyway.

> But as long as you don't get too fancy--and make sure all your

> dialogs are modal--you shouldn't have any problems.

So if an appliation uses multiple frames or non-modal dialogs with at

least two of them having text components in them things may go berzerk.

I think I'll use an Action wrapper that requests the focus for the text

component before delegating the stuff to the wrapped Action ...

IMHO this single Action object is a strange design in this particular scenario.

Thanks for your reply, much appreciated and,

kind regards,

Jos

JosAHa at 2007-7-15 5:13:42 >

Camickr, thank you very much for your reply and your efforts. Have a look

at your demo, augmented by me a bit; press the 'paste' button and see

the (not so funny) behaviour:import java.awt.*;

import javax.swing.*;

//import javax.swing.event.*;

import javax.swing.text.*;

public class TextAreaCopy extends JFrame

{

public TextAreaCopy()

{

createDialog(0);

createDialog(500);

}

private void createDialog(int x)

{

JDialog dialog = new JDialog();

dialog.setModal( false );

dialog.setLocation(x, 0);

JToolBar toolBar = new JToolBar();

dialog.getContentPane().add(toolBar, BorderLayout.NORTH);

JTextArea textArea1 = new JTextArea(5, 40);

JScrollPane scrollPane1 = new JScrollPane( textArea1 );

dialog.getContentPane().add(scrollPane1, BorderLayout.CENTER);

JTextArea textArea2 = new JTextArea(5, 40);

JScrollPane scrollPane2 = new JScrollPane( textArea2 );

dialog.getContentPane().add(scrollPane2, BorderLayout.SOUTH);

KeyStroke controlC = KeyStroke.getKeyStroke("control C");

Action copy1 = textArea1.getActionMap().get(textArea1.getInputMap().get(controlC));

toolBar.add( new JButton(copy1) );

KeyStroke controlP = KeyStroke.getKeyStroke("control V");

Action paste1 = textArea1.getActionMap().get(textArea1.getInputMap().get(controlP));

toolBar.add( new JButton(paste1) );

dialog.pack();

dialog.setVisible( true );

}

public static void main(String[] args)

{

TextAreaCopy frame = new TextAreaCopy();

frame.setDefaultCloseOperation( EXIT_ON_CLOSE );

frame.pack();

frame.setLocationRelativeTo( null );

frame.setVisible( true );

}

}

kind regards,

Jos

JosAHa at 2007-7-15 5:13:42 >

> The code could be modified to get the parent window of the source

> button and the parent window of the text component. If they are not the

> same, then don't do the paste. Thats all I can think of.

I don't think that would be wanted behaviour, e.g. sometimes one wants

to copy something from one JTextArea and paste it to another one. Now

a 'paste' button that visually 'belongs' to the other area pastes the text to

the original JTextArea if that was the last text component that had the focus.

(also see your example augmented by me)

thanks for thinking with me and

kind regards,

Jos

JosAHa at 2007-7-15 5:13:42 >

> just a thought, would this do what you want

[ code snipped ... ]

It does exactly what I want; thanks a bunch. It's so obvious; I can't

believe I overlooked those obvious cut(), copy(), paste() methods ...

I told you I got lost in the documentation in my OP ;-)

Thanks again, your solution is just simple and elegant; much better

than mine.

kind regards,

Jos

JosAHa at 2007-7-21 13:02:18 >