So I am new to gui stuff and I want to make a simple program to print a circle to represent the sun, and then near it I want to print another circle to represent a planet. My issue is when I added the method paintPlanet, all that is returned in the gui window is blank screen now. Even when I commented paintPlanet out, the circle for the sun will not print and I am left with a blank window. Can someone help me figure out where I went wrong how to fix it so both circles will print? I am new to GUI things so be easy on me :)
import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JPanel;
public class PlanetsLogic extends JPanel
{
private static final long serialVersionUID = 1L;
public void paintSun(Graphics g)
{
super.paintComponent(g);
//create circle and fill it as yellow to represent the sun
g.setColor(Color.YELLOW);
g.drawOval(100, 75, 75, 75);
g.fillOval(100, 75, 75, 75);
} //end paintSun
public void paintPlanet(Graphics g)
{
super.paintComponent(g);
//create circle and fill it as yellow to represent the orbiting planet
g.setColor(Color.BLUE);
g.drawOval(75, 75, 75, 75);
g.fillOval(75, 75, 75, 75);
}//end paintPlanet
}//end class PlanetsLogic
MAIN:
import javax.swing.JFrame;
public class OrbitingPlants_main
{
public static void main(String[] args)
{
PlanetsLogic planet = new PlanetsLogic();
JFrame frame = new JFrame();
frame.setTitle("Orbiting Planets");
frame.setSize(300, 300);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(planet); //add panel onto frame
frame.setVisible(true);
}
}
Your paintSun and paintPlanet methods will never be magically called. Instead your JPanel needs to override the paintComponent method as all drawing is done there. You can even call your paintSun and paintPlanet methods from within paintComponent, but I would recommend calling the super.paintComponent(g) only once and only from within your paintComponent method override itself.
e.g.,
// use #Override to ask the compiler to check if this method is a true override
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g); // HERE!
paintSun(g);
paintPlanet(g);
}
public void paintSun(Graphics g) {
// super.paintComponent(g); // nope, not here!
//create circle and fill it as yellow to represent the sun
g.setColor(Color.YELLOW);
g.drawOval(100, 75, 75, 75);
g.fillOval(100, 75, 75, 75);
} //end paintSun
public void paintPlanet(Graphics g) {
// super.paintComponent(g); // NO don't call this here
//create circle and fill it as yellow to represent the orbiting planet
g.setColor(Color.BLUE);
g.drawOval(75, 75, 75, 75);
g.fillOval(75, 75, 75, 75);
}//end paintPlanet
Related
So, I need to make the stick-man movable by a user-input. When the user clicks on a part (Head, hands, feet and posterior) and he should move, and have no idea how to go about this..
If possible, there also needs to be a confine around the character, likely rectangular, so that there is a limit to how far each part can be pulled.
See below for my code;
// Created by Charlie Carr - (28/11/17 - /11/17)
import java.awt.*;
import java.applet.Applet;
import javax.swing.*;
import java.awt.Graphics;
import java.awt.geom.*;
import java.awt.image.BufferedImage;
//Imports complete
//Suppress warning about undeclared static final serialVersionUID field in VS Code
#SuppressWarnings("serial")
public class Animator extends JPanel {
public static class AnimatorWindow extends JPanel {
public void paint(Graphics page) {
setBackground(Color.gray);
setForeground(Color.white);
super.paintComponent(page);
page.drawString("Stickmen Animation Station", 150, 15);
//draw the head
//x1, y1, x2, y2
page.drawOval(90, 60, 20, 20);
// draw the body
page.drawLine(100, 80, 100, 110);
// draw the hands
page.drawLine(100, 90, 80, 105);
page.drawLine(100, 90, 120, 105);
//draw the legs, he hasn't a leg to stand on..
page.drawLine(100, 110, 85, 135);
page.drawLine(100, 110, 115, 135);
}
}
public static void main(String[] args) {
AnimatorWindow displayPanel = new AnimatorWindow();
JPanel content = new JPanel();
content.setLayout(new BorderLayout());
content.add(displayPanel, BorderLayout.CENTER);
//declare window size
int x = 480;
int y = 240;
JFrame window = new JFrame("GUI");
window.setContentPane(content);
window.setSize(x, y);
window.setLocation(101, 101);
window.setVisible(true);
}
}
Use MouseListenerto deal with mouse events.
Also, you should override the paintComponent() method instead of paint(), because paint() also paints the border and other stuff.
public static class AnimatorWindow extends JPanel implements MouseListener{
public AnimatorWindow(){
setBackground(Color.gray);
setForeground(Color.white);
//add the listener
addMouseListener(this);
}
public void paintComponent(Graphics page) {
super.paintComponent(page);
//You should not alter the Graphics object passed in
Graphics2D g = (Graphics2D) page.create();
//draw your stuff with g
g.drawString("Stickmen Animation Station", 150, 15);
.......
//finish
g.dispose();
}
public void mouseEntered(MouseEvent e){}
public void mouseExited(MouseEvent e){}
public void mousePressed(MouseEvent e){}
public void mouseReleased(MouseEvent e){}
public void mouseClicked(MouseEvent e){
//implement your clicking here
//Use e.getX() and e.getY() to get the click position
}
}
For more on swing events, check this site
EDIT: Your problem also includes animation, and you can use a javax.swing.Timer to do that.
I need to be able to display filled rectangles for the program i am creating, however the following code produces the following GUI with only the black text 'test' after calling start then change, could anyone explayin why please?
package core;
import java.awt.Color;
import java.awt.Graphics2D;
import javax.swing.JFrame;
#SuppressWarnings("serial")
public class GUI extends JFrame{
private Graphics2D g;
private int[][][] clickable;
public void start(){
this.setSize(500, 500);
this.setTitle("Placeholder");
this.setVisible(true);
g = (Graphics2D) this.getGraphics();
}
public void change(String[] fields, int type[], boolean forwards){
g.setColor(new Color(28,35,57));
g.drawRect(0, 0, 100, 100);
g.drawRect(50, 50, 150, 150);
g.fillRect(0, 0, 100, 100);
g.drawString("test", 300, 300);
}
}
And here is what it looks like ..
Drawing on Swing components (like JFrame) works only in onPaint event.
The event can be fired using repaint() method.
This event fires automatically when frame needs to be painted.
To implement this event behavior override paint() method.
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JFrame;
public class GUI extends JFrame{
private Graphics2D g;
public void start(){
this.setSize(500, 500);
this.setTitle("Placeholder");
this.setVisible(true);
}
public void change(){
g.setColor(new Color(28,35,57));
g.drawRect(0, 0, 100, 100);
g.drawRect(50, 50, 150, 150);
g.fillRect(0, 0, 100, 100);
g.drawString("test", 300, 300);
}
public void paint(Graphics g2d){
g = (Graphics2D) g2d;
change();
}
public static void main(String[] args){
GUI frame = new GUI();
frame.start();
}
}
This question already has an answer here:
The point of origin in my GUI is off by about 25/26 pixels
(1 answer)
Closed 7 years ago.
I started experimenting with JFrame and my first task I wanted to accomplish was drawing a 50px square with the fillRect() or drawRect() method. Unfortunately after running, the program showed a rectangle instead of a square.
My code:
package javaapp;
import java.awt.Graphics;
import javax.swing.JFrame;
public class JavaApp extends JFrame{
public JavaApp() {
setTitle("Voorbeeld");
setSize(250, 250);
setResizable(false);
setVisible(true);
setDefaultCloseOperation(EXIT_ON_CLOSE);
}
public void paint (Graphics g){
g.fillRect(0, 0, 50, 50);
}
public static void main(String[] args) {
new JavaApp();
}
}
The frame actually starts way at the top left corner. It's simple to just add a JPanel and paint on it instead. Otherwise you could call setUndecorated(true)
class JavaApp extends JFrame {
public JavaApp() {
setTitle("Voorbeeld");
setSize(250, 250);
setResizable(false);
setVisible(true);
setDefaultCloseOperation(EXIT_ON_CLOSE);
add(new JPanel() {
protected void paintComponent(Graphics g) {
g.setColor(Color.BLACK);
g.clearRect(0, 0, getWidth(), getHeight());
g.fillRect(0, 0, 50, 50);
}
});
}
public static void main(String[] args) {
new JavaApp();
}
}
Use paintComponent instead.
I am using a JFrame and a pane and trying to draw a simple square.
My painting is not showing up. I made I set the color to black so it should be visible.
Code:
package W2;
import java.awt.Color;
import java.awt.Container;
import java.awt.Graphics;
import javax.swing.*;
public class W2 {
JFrame frame = new JFrame("W2");
public W2(){
Container pane = new Container();
frame.setContentPane(pane);
frame.setSize(750,500);
frame.setLocationRelativeTo(null);
frame.setResizable(false);
frame.setVisible(true);
}
public void paint(Graphics g){
g.setColor(Color.BLACK);
g.fillRect(50, 50, 50, 50);
}
public static void main(String args[]){
new W2();
}
}
The paint method won't be called because it's not part of a object that can be painted.
See Performing Custom Painting for details about how painting is done in Swing
For example...
frame.setContentPane(new JPanel() {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.BLACK);
g.fillRect(50, 50, 50, 50);
}
});
I'm working on a uni project which is to create a dice face using 2d graphics shapes. I have got that all done but I have a problem: I want my shape to change size when I adjust the window size, instead of just staying still also so that it stays in the middle.
I thought I could set the position so that is was center tried this but didn't work. I'm not sure but would I have to write co-ordinates so that its changes size with the window? Any help with both problems would be great.
GUI setup code
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import javax.swing.JComponent;
import javax.swing.JFrame;
public class DiceSimulator {
public static void main(String[] args) {
JFrame frame = new JFrame("DiceSimulator");
frame.setVisible(true);
frame.setSize(400, 300);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
draw object = new draw();
frame.add(object);
frame.setLocationRelativeTo(null);
object.drawing();
}
}
Painting code
import javax.swing.*;
import java.awt.*;
//import java.util.Random;
public class draw extends JComponent {
public void drawing() {
repaint();
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
//Random1 random = new Random1();
Graphics2D g2 = (Graphics2D) g;
g.setColor(Color.BLACK);
Rectangle box = new Rectangle(115, 60, 150, 150);
g2.fill(box);
g.setColor(Color.WHITE);
g.fillOval(145, 75, 30, 30);
g.setColor(Color.WHITE);
g.fillOval(205, 75, 30, 30);
g.setColor(Color.WHITE);
g.fillOval(145, 115, 30, 30);
g.setColor(Color.WHITE);
g.fillOval(205, 115, 30, 30);
g.setColor(Color.WHITE);
g.fillOval(145, 155, 30, 30);
g.setColor(Color.WHITE);
g.fillOval(205, 155, 30, 30);
}
}
In the paintComponent() method you need to use
int width = getSize().width;
int height = getSize().height;
to get the current size of the component as it changes size when the frame changes size. Then based on this current size you can draw your components. This means that you can't hardcode the values in your drawing methods.
If you want to shift all the drawing coordinates with one command then you can use:
g.translate(5, 5);
at the top of the method. Then all hardcoded (x, y) values will be adjusted by 5 pixels each. This will allow you to change the centering of the drawing.