The goal here is that I can click a color and shape, then two points on the figuresPanel. That colored shape is filled in on the figuresPanel, and I can add shapes on top of each other etc. I also need the current date to be displayed in the corner of the figuresPanel, on top of all the painted shapes. I am able to create shapes (though they always cover the date) no problem, but whenever I resize or minimize the window, all the painted shapes disappear. I've tried implementing quite a few different methods from Graphics (update, paint, redraw, etc.) and haven't found one that corrects this issue. I thought paintComponent() would take care of all that, but apparently not. Feel free to point out anything that could be implemented in a better way, always happy to learn something new.
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
drawFigures();
figuresPanel.add(dateLabel, c);
}
#Override
public Dimension getPreferredSize() {
return (new Dimension(800, 600));
}
private void addFigure(Figure figure) {
figureList.add(figure);
listArea.append(figure.toString() + "\n");
figure.fill(getGraphics());
}
private void drawFigures() {
for (Figure f : figureList) {
f.fill(getGraphics());
}
}
I would suggest a few things that might help you.
In your method drawFigures() instead of using getGraphics(), why don't you pass the instance of Graphics in paintComponentMethod as a parameter to the method and use it to draw the object. This will make sure that you are drawing on the same instance of the Graphics that you are using to paint.
In your method addFigure(Figure figure) I would suggest you remove the line figure.fill(getGraphics());, to draw the object completely. Instead in your mouseClicked(MouseEvent event) method after your switch statement insert:
revalidate();
repaint();
This should actually take care of the drawing of the objects are done exactly on the same Graphics object that is being used to display the components.
I hope that this shall be helpful.
Related
I'm trying to make a simple application to draw shapes to a panel in a jFrame. The GUI is a NetBeans generated jFrame. The application has three panels. the first two hold button groups to select the shape and a color. There's a button to draw the shape to the third panel once the selections are made.
What the GUI looks like
Unfortunately I'm having no love and can't make it work. For now I just want to get the button to draw a shape then I'll add the button functionality. Here's the code I have so far.
private void btnDrawShapeActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
Draw shape = new Draw();
pnlDrawPad.add(shape); //pnlDrawPad is the name of the jPanel
shape.drawing();
}
import javax.swing.*;
import java.awt.*;
public class Draw extends JPanel{
public Draw(){
super();
}
public void drawing(){
repaint();
}
//#Override <-- gives error "method does not override or implement a method from a supertype"
public void paintCompnent(Graphics g){
super.paintComponent(g);
g.setColor(Color.RED);
g.drawString("Hello World!",40,30);
}
}
When I click the "Draw Shape" button nothing happens. I've been searching for a couple days now and am not finding the answer. Actually, its making me more confused as to what to do.
How to deal with this?
Don't keep creating new panels for each shape.
Instead you need a single panel with an ArrayList of objects you want to paint. Then you customize the paintComponent(...) method of the panel to iterate through all the objects in the panel and paint them.
So you button will just add another object to the ArrayList and then invoke repaint() on the panel.
Check out Custom Painting Approaches. The DrawOnComponent example shows how to paint a Rectangle objects from an ArrayList to get you started.
I found that with NetBeans you don't need to Override the paintComponents() method. Since all the GUI stuff is done when you design it, you merely need to add the drawings to the panel or what ever you need to do. I found you that by declaring and instantiating a 2D graphics object then drawing it to the place you want.
private void btnDrawShapeActionPerformed(java.awt.event.ActionEvent evt) {
int centerX;
int centerY;
Graphics2D drawFx = (Graphics2D)pnlDrawPad.getGraphics();
drawFx.setColor(Color.ORANGE);
centerX = (int)(458*Math.random());
centerY = (int)(440*Math.random());
drawFx.fillOval(centerX-50, centerY-50, 100, 100);
drawFx.dispose();
}
Worked like a charm so now every time I push the draw shape button it draws a shape to the panel in a different location every time. I've since put in the radio button functionality to change shape color and fill and added a button to clear the screen.
Not sure if this is the ideal way to do it but for this stupid simple little program it works well enough and I'm done stressing over it.
I have a little issue with my GUI in NetBeans. I draw images (dots) when a user clics in a JPanel at the mouse clic location. This part works just fine. I store each image locations in two different ArrayList that contains the X location and Y location. Now what I want to do is to delete the latest image drawn in the Panel after a button is clicked. So what I did is remove the last index of both ArrayList, and then call repaint() to draw all the images from the locations in both X and Y ArrayList (code below).
What is weird is that I need to resize the GUI (put it in full screen or just change its' size) in order for the drawn images to show up again in the JPanel otherwise, the panel remains empty.
Here's the parts of code that are affected :
public void paint(Graphics g) {
super.paint(g);
for(int i=0;i<=listePointsX.size()-1;i++) {
try{
BufferedImage icon = ImageIO.read(getClass().getResourceAsStream("/myimage.png"));
Graphics graphe = jPanel1.getGraphics();
graphe.setColor(Color.BLACK);
graphe.drawImage(icon, this.listePointsX.get(i),this.listePointsY.get(i), rootPane);
}catch(Exception e1){
}
}
private void jButtonUndoActionPerformed(java.awt.event.ActionEvent evt) {
if(listePointsX.size()>0){
int lastObject= listePointsX.size();
listePointsX.remove(lastObject-1);
listePointsY.remove(lastObject-1);
jPanel1.repaint();
}
else{
}
}
Any idea what I need to do to some kind of "refresh" the whole thing? Am I doing something wrong? Tried searching about that but did not find anyting...
Graphics graphe = jPanel1.getGraphics(); is NOT how painting should work, instead, you should have overriden the panel's paintComponent method and painted the points within in.
See Painting in AWT and Swing and Performing Custom Painting for more details about how painting works in Swing
Instead, your panel should be doing ALL the work, managing the points in the ArrayList and painting them. You parent component "might" have the ability to add or remove points if that meets your design requirements, but the core responsibility remains with the panel.
Avoid performing any long running or block operations within the paint methods, they should run as fast as possible. Since the image never changes, you should simply load once (either when the class is constructed or when you first need the image) and keep using the same reference.
Alright it worked just fine now. I had to do it the way you told me up here. I created a new class that extends jPanel (below). Then in my main Form, had to create an object of this class. Whenever a user makes a click, it will call this Drawing class object and add an item to the ArrayList (this object manages everything regarding created points... It looks like this :
public class MyDrawingClass extends JPanel {
ArrayList<Integer> arrayListPointX = new ArrayList<>();
ArrayList<Integer> arrayListPointY = new ArrayList<>();
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
try{
BufferedImage icon = ImageIO.read(getClass().getResourceAsStream("/images/dot.png"));
g.setColor(Color.BLACK);
if(arrayListPointX.size()<=0){
...
}
else{
for(int i=0;i<listePointsX.size();i++){
g.setColor(Color.BLACK);
g.drawImage(icon, listePointsX.get(i), listePointsY.get(i), rootPane);
}
}
}catch(Exception e){
...
}
}
So if I want to "undo", let's say my object of "MyDrawingClass" is called "draw". I can do : draw.arrayListPointX.remove(draw.arrayListPointX.size()-1); and call repaint(); to display remaining points.
Thanks for your tips appreciate it ! :)
I have a panel in which i draw a number of graphics objects on using the paintComponent method and the Graphics methods to draw.
I need to create a button, that you click and then it clears the panel.
example :
JButton clear = new JButton("Clear");
public void actionPerformed(ActionEvent e){
if(e.getSource()==clear){
//button code here
}
}
What i need is the code that goes inside that IF statement.
The paintComponent method will get called everytime a repaint is called and this method draw what you write in it everytime.If you want to clear a screen of object then you must remove the object(a button for example) from the panel/frame on the button click function.
It is not a good practice to write logic code in the paintComponent method with boolean etc.
Do something like this:
private boolean clear = false;
public void paintComponent(Graphics g) {
super.paintComponent(g);
if(clear)
return;
}
// all your graphics here
}
public void actionPerformed(ActionEvent e){
if(e.getSource()==clearButton){
clear = true;
repaint();
}
}
Don't forget to change back the clear flag, at some point of the program, when you want to allow drawing.
Check out Custom Painting Approaches for the two common ways of doing custom painting:
paint objects contained in a List, in which case you would clear the List
paint onto a BufferedImage, in which case you would clear the BufferedImage
The examples code shows how "Clear" would be done in both cases.
I have a program where the base panel is just drawing the background (trees, water, etc), and i have a player and other objects moving around the screen. I don't want to call repaint() on the whole thing because it slows me down because it repaints the whole thing. When I try to add a new panel on top that will be repainted a lot and handle moving objects, nothing happens in my code. This is what I have in the constructor for the first
public GamePanel()
{ //some code
top = TopPanel();
top.setSize(this.getSize());
add(top);
//some more code
}
and then in the class for the toppanel
public TopPanel()
{
}
public void paintComponent(Graphics g)
{
i.drawItem(//);
player.draw(//fields);
}
And no matter what I do, I can't get anything to show up on the panel when i run it.
My general approach when rendering a complex but static 'background' with other things painted on top is to draw the background to a BufferedImage and simply redraw the image before painting the dynamic parts.
Ok I'm wondering why the code below will not display the JLabel.
MyPanel is getting added correctly to a JFrame and everything because it all displays but will not draw the JLabel. Any help is appreciated.
public class MyPanel extends JPanel {
private Root root;
...
public void paintComponent(Graphics g)
{
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
root.paint(g2);
}
}
class Root {
private Node1 node1;
...
public void paint(Graphics g) {
node1.paint(g);
}
}
class Node1 {
...
public void paint(Graphics g) {
JLabel jtp = new JLabel();
jtp.setLocation((int) x, (int) y);
jtp.setSize((int) width, (int) height);
jtp.setLocation(40, 40);
jtp.setSize(40, 40);
jtp.setText("Hello world");
//jtp.setVisible(true);
jtp.paint(g);
}
}
I suggest that you don't add Components to a Container in a paint method as 1) you do not have absolute control when or even if a paint method will be called and 2) paint and paintComponent have to be as blazing fast as possible, and this is not the time or place to update a GUI. 3) Since paint is often called many times, you will be adding components many times to your container, and all out of your direct control.
Also, while you're adding a component into Root (whatever Root is since it doesn't extend JComponent, JPanel, or similar) in the paint method, the Root object is never added to anything else that I can tell, and so it makes sense that nothing "added" to a component that is not added eventually to a top-level window will be visible.
Bottom line: I think you need a gui re-design as your solution. If you tell us more about it we can help you with it. Next we'll need to talk about use of layout managers and why setting absolute position and sizes of components is usually frowned on.
If anything I say is confusing, please ask for clarification, or if anything is wrong, please help me correct it!
You should not create your JLabel inside the paint method - instead, create it once when initializing your MyPanel. Your label is kind of a renderer component for your nodes, which in principle is a good thing. You may look how the renderers for JTable, JList, JTree work.
In your case, don't set the location of your label (it does not change anything, since it's paint-method expects its graphics object to be oriented by its own upper left corner), instead translate the Graphics-context:
Graphics copy = g.create((int)x, (int)y, (int)width, (int)height);
jtp.paint(copy);
(Graphics2D has some more fancy methods for shifting, rotating, scaling the context, too.)
Other than this, I don't see any problems. Make sure your Node1.paint() method gets actually called by putting some System.out.println() in there.