how to print contents of a jpanel as text? - java

I'm using netbeans and I have the code to print a jpanel and it works fine. However, its output is that it prints the jpanel as an image. This is not ideal for me as it also prints a faded gray color in the background which is the size of the jpanel. I only want to print the text in the jpanel which consists of many jlabels. Is there a way to print the contents of a jpanel as text and not an image?
This is the code that I used to print the contents of my jpanel
PrinterJob job = PrinterJob.getPrinterJob();
job.setJobName("jPanel13");
job.setPrintable (new Printable() {
public int print(Graphics pg, PageFormat pf, int pageNum){
if (pageNum > 0){
return Printable.NO_SUCH_PAGE;
}
Graphics2D g2 = (Graphics2D) pg;
g2.translate(pf.getImageableX(), pf.getImageableY());
jPanel13.paint(g2);
return Printable.PAGE_EXISTS;
}
});
boolean ok = job.printDialog();
if (ok) {
try {
job.print();
} catch (PrinterException ex) {
}
This is a printscreen of the jpanel that I need to print. In my program, the text values of the jlabels can be changed by the user. The jlabels texts will then be printed to fill in the blank lines a form. The form will already have writing on it; it is only the blank lines that I will fill-up when printing. That is why it is important that the jlabels are positioned in that way.
http://i.stack.imgur.com/kPKWe.jpg

If the JPanel background is the only problem, you can call print() on it instead of paint(), and override printComponent() to do nothing (the default just calls paintComponent()).
Alternately, just set the background color to white while printing.

Related

Black flashing around drawn image

I'm currently trying to draw an image to a JFrame (just a nonsense test image). In the code bite below, the image is drawn to the JFrame, but the area around the image that doesn't fill JFrame is black that rapidly flashes.
Here is the code below:
try {
myImage = ImageIO.read(ImagesMain.class.getResource("/Textures/TestImage.png"));
}catch(Exception e) {
e.printStackTrace();
}
BufferStrategy strategy = null;
while(strategy == null) {//I know this is terrible practice, just doing this way because its inside main
strategy = myCanvas.getBufferStrategy();
if(myCanvas.getBufferStrategy() == null) {
myCanvas.createBufferStrategy(3);
}
}
myFrame.setVisible(true);
//Rendering part
while(true) {
do {
do {
g = strategy.getDrawGraphics();
g.setColor(Color.WHITE);
g.drawImage(myImage, 20, 20, null);
g.dispose();
}while(strategy.contentsRestored());
strategy.show();
}while(strategy.contentsLost());
}
I've tested and retested my code several times to no avail. I should also add that this is all done in the main method (for testing purposes). Long story short, how do I display my image without the unnecessary black flashing around the image?
When this happens, it is because one is not clearing the Frame to which they are drawing. In this instance,
g.clearRect(x, y, height, width); is needed to clear the drawing frame and display a clear image.
Answer courtesy of #MadProgrammer above, in comments.

Copy the contents of a JPanel onto a BufferedImage

On the first time through, I insert BufferedImages from a list onto my JPanel from my extended class:
#Override
protected void paintComponent(Graphics g){
super.paintComponent(g);
if (controlWhichImage == 1){
for (BufferedImage eachImage : docList){
g.drawImage(eachImage, 0,inty,imageWidth,imageHeight,null);
intx += eachImage.getWidth();
inty += eachImage.getHeight() * zoomAdd;
}
if (intx >= this.getWidth() || inty >= this.getHeight()){
inty = 0;
}
The next time I want to copy the contents of the JPanel to a BufferedImage:
public void recordImage(){
controlWhichImage = 2;
this.createdImage = new BufferedImage(this.getWidth(), this.getHeight(), BufferedImage.TYPE_INT_ARGB);
Image halfWay = this.createImage(this.getWidth(), this.getHeight());
//now cast it from Image to bufferedImage
this.createdImage = (BufferedImage) halfWay;
}
And then, take the modified BufferedImage and draw it back onto the JPanel:
if (controlWhichImage == 2){
g.drawImage(this.createdImage,0,inty,this.getWidth(),this.getHeight(),null);
}
This second time I get a blank panel.
I hope this is clear, any help gratefully received.
Sorry for my poor explanation. I will try to make myself clearer.
On each iteration the user is able to draw on the image in the Jpanel.
What I want to do is copy the user altered jpanel into a buffered image which will then be in the Jpanel to be edited again by the user.
This continues until the user selects print.
So apart from the code that I have put here are the controls for drawing by the user, at the moment I am struggling with putting the initial updated image from the original Jpanel into a bufferedImage and then back to the JPanel.
Hope this makes it somewhat clearer
To draw to a BufferedImage, you would do something similar to what you already do in your paintComponent method, but with your BufferedImage. Perhaps a method like:
// imgW and imgH are the width and height of the desired ultimate image
public BufferedImage combineImages(List<BufferedImage> docList, int imgW, int imgH) {
// first create the main image that you want to draw to
BufferedImage mainImg = new BufferedImage(imgW, imgH, BufferedImage.TYPE_INT_ARGB);
// get its Graphics context
Graphics g = mainImage.getGraphics();
int intx = 0;
int inty = 0;
// draw your List of images onto this main image however you want to do this
for (BufferedImage eachImage : docList){
g.drawImage(eachImage, 0,inty,imageWidth,imageHeight,null);
intx += eachImage.getWidth();
inty += eachImage.getHeight() * zoomAdd;
}
}
// anything else that you need to do
g.dispose(); // dispose of this graphics context to save resources
return mainImg;
}
You could then store the image returned into a varaible and then draw it in your JPanel if desired, or write it to disk.
If this doesn't answer your question, then again you'll want to tell more and show us your MCVE.

How do you embed a resizable JPanel inside of a JTextPane?

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.

Good practice for drawing and zooming image?

I have a JScrollPane with a JPanel where I can draw by mouse and code.
I need the possibility to zoom on details in my drawing.
But soon I get a outOfMemoryError. I think because I make my drawing to big while zooming.
This is my code:
private BufferedImage _bufferedImage;
private int _panelWidth = 2000, _panelHeight = 1500;
#Override
public void paintComponent(Graphics g){
super.paintComponent(g);
if(_bufferedImage != null){
g.drawImage(_bufferedImage, 0, 0, this);
}
}
public void draw(float zoomFactor){
try {
int width = (int)(_panelWidth * zoomFactor);
int height = (int)(_panelHeight * zoomFactor);
_bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2 = _bufferedImage.createGraphics();
g2.setBackground(Color.WHITE);
g2.setPaint(Color.BLACK);
g2.scale(zoomFactor, zoomFactor);
drawHouse(g2); ...
g2.dispose();
}
catch (Exception e) {
e.printStackTrace();
}
repaint();
}
There must be better practice then what I did.
I can just draw the area of the scrollpane, but then I can't use the scrollbars,
then I have to use buttons with arrow up, right, left, down to scroll in my drawing.
Anyone who can me give a hint?
but then I can't use the scrollbars
Scrollbars work when the preferred size of the component is greater than the size of the scrollpane. If you are zooming the image in the paintComponent() method then you would also need to override the getPreferredSize() method to return the appropriate size of the image that takes into account the zooming factor.
So in your case the preferred size would be the size of your image.
If you want to zoom in, I am assuming you are no trying to make "bigger pixels", but to draw the same figures at a higher scale. In that case, you should not be using a BufferedImage at all -- instead, you should draw to a suitably scaled JPanel or similar. You can always take a snapshot of whatever you are rendering whenever you need it; but rendering to a BufferedImage without need is wasteful (of time and memory).
See this answer for details.

java: How to print JForm

I am having code of print a string, which is passed in the program itself. Here I am calling this code on Print button to get hard copy. Now I want to print a JForm in the same code, But I am not getting how to do this. JForm having some labels and textfields of user's details. This is the code where I am printing a string"Hello World".
public class PrintClass implements Printable, ActionListener {
public int display(Graphics g, PageFormat pf, int page) throws
PrinterException {
if (page > 0) { /* We have only one page, and 'page' is zero-based */
return NO_SUCH_PAGE;
}
/* User (0,0) is typically outside the imageable area, so we must
* translate by the X and Y values in the PageFormat to avoid clipping
*/
Graphics2D g2d = (Graphics2D)g;
g2d.translate(pf.getImageableX(), pf.getImageableY());
/* Now we perform our rendering */
g.drawString("Hello World", 100, 100);
/* tell the caller that this page is part of the printed document */
return PAGE_EXISTS;
}
Please help me to call constructor of a JForm, instead of pass the string.
Draw the Graphics of your current JFrame into a BufferedImage and then draw the image into the printer's Graphics.
Graphics g = myFrame.getContentPane().getGraphics();
// draw graphics into an image
// draw the image into the printer's graphics
It is important to note that you should always get a new Graphics object from your JFrame whenever you want to print the form content

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