There are many questions of the converse, inserting a JTextPane into a JPanel. This is not my question. I need to be able to insert a custom JPanel (with drag and drop, drag, and mouse click listeners) into a JTextPane, which is then put into a JScrollPane, and finally put into a JFrame for displaying. The reason is because I need to have an image with support for resizing by dragging it within a chat client, which is itself primarily text.
Conveniently enough, there is a relevant method in JTextPane: insertComponent(Component c), but whenever I use it, my components end up being squished to exactly one line of text worth of space (even though they report having a larger size). This is perfect for plain buttons, but if I need anything larger, I'm out of luck. I can insert images by themselves just fine, with ImageIcons, but images wrapped inside a JPanel don't work at all (plus I can't add any listeners to ImageIcons, since they're not GUI elements; overriding one isn't an option).
Whenever a user drags an image into the chat client, this bit of code inserts the custom JPanel:
private void sendImage(BufferedImage im, int cl) throws IOException {
if(output == null) return;
//Send the image itself over to your friend
byte[] toSend = toBytes(im, cl);
sendString(nickname.hashCode() + "image"); //Header for image
output.writeInt(toSend.length); //Tells how many bytes to read.
output.write(toSend);
//Let the user know that the image was sent
float linmb = (float)(toSend.length / 1048576.0); //Size of file sent
addText("\n" + nickname + " sent an image! (" + linmb + " MB)\n", Color.RED.darker());
//Show the image itself
DraggerPanel d = new DraggerPanel(im, true);
text.insertComponent(d);
d.repaint();
//Spacer
addText("\n");
}
This is the source for DraggerPanel, the custom JPanel that holds an image:
public class DraggerPanel extends JPanel {
private BufferedImage image; //The image we're drawing
private Point startingPoint = null; //Starting point for resizing
private boolean first = true; //Is this the first drag?
private boolean lockedDrag; //If true, then lock x and y to be proportionally dragged.
public DraggerPanel(BufferedImage image, boolean lockedDrag) {
super();
this.image = image;
this.lockedDrag = lockedDrag;
//The listener for dragging events.
addMouseMotionListener(new MouseMotionListener() {
private int inWidth = 0, inHeight = 0; //Initial height and width values
private double ratio = 0; //Ratio of height to width for locked drag.
public void mouseDragged(MouseEvent m) {
if (first) { //If we're first, record initial position.
startingPoint = m.getPoint();
first = false;
inWidth = getWidth();
inHeight = getHeight();
ratio = (double)inHeight / inWidth;
} else { //Otherwise, change the size of the window.
if (!lockedDrag) {
int w = (int)startingPoint.getX() - m.getX();
int h = (int)startingPoint.getY() - m.getY();
setSize(Math.abs(inWidth - w), Math.abs(inHeight - h));
} else {
int w = (int)startingPoint.getX() - m.getX();
int h = (int)((double)ratio * w);
setSize(Math.abs(inWidth - w), Math.abs(inHeight - h));
}
}
repaint();
}
public void mouseMoved(MouseEvent m){
}
});
//Lets us know when you're not dragging anymore.
addMouseListener(new MouseAdapter(){public void mouseReleased(MouseEvent m){first = true;}});
//Set appropriate size.
if(image != null) setSize(image.getWidth(), image.getHeight());
else setSize(200,200);
//We're live, baby.
setVisible(true);
}
public void paint(Graphics g) {
if (image == null) super.paint(g);
else g.drawImage(image, 0, 0, getWidth(), getHeight(), null);
}
}
Update 1: I followed @camickr 's advice, and updated the DraggerPanel to use setPreferredSize instead of setSize, as well as overrode paintComponent() instead of paint(). Now, the image has the proper height, but is stretched to the width of the JTextPane (which seems like what it was doing before). Furthermore, resizing doesn't seem to matter- the image doesn't change its size at all. Mouse events are definitely going through, but not affecting the size. It seems as though the original problem isn't fully resolved, since the JPanel's size isn't what I need it to be, and the solution to that will also lead to a solution to the resizing issue.
Update 2: I did it! I finally did it. To the future time travelers who have this issue, I basically yelled at the JTextPane by not only using setSize() in my overridden JPanel, but also setPreferredSize() and setMaximumSize(). The preferred one works well with height, and the maximum sets the width (God knows why). Thanks for your tips, @camickr!
my components end up being squished to exactly one line of text worth of space (even though they report having a larger size).
I would guess the size is not important.
I would think you need to override the getPreferredSize() method of your DraggerPanel to return the preferred size of the panel so the text pane can display the panel.
Also, custom painting is done by overriding the paintComponent(...) method NOT the paint() method.