JLabel animation in JPanel
- by Trizicus
After scratching around I found that it's best to implement a custom image component by extending a JLabel. So far that has worked great as I can add multiple "images" (jlabels without the layout breaking. I just have a question that I hope someone can answer for me.
I noticed that in order to animate JLabels across the screen I need to setlayout(null); and setbounds of the component and then to animate eventually setlocation(x,y);. Is this a best practice or a terrible way to animate a component? I plan on eventually making an animation class but I don't want to do so and end up having to chuck it.
I have included relevant code for a quick review check.
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JPanel;
import javax.swing.Timer;
public class GraphicsPanel extends JPanel {
private Timer timer;
private long startTime = 0;
private int numFrames = 0;
private float fps = 0.0f;
private int x = 0;
GraphicsPanel() {
final Entity ent1 = new Entity();
ent1.setBounds(x, 0, ent1.getWidth(), ent1.getHeight());
add(ent1);
//ESSENTIAL
setLayout(null);
//GAMELOOP
timer = new Timer(30, new ActionListener() {
public void actionPerformed(ActionEvent e) {
getFPS();
incX();
ent1.setLocation(x, 0);
repaint();
}
});
timer.start();
}
public void incX() { x++; }
@Override
public void paintComponent(Graphics g)
{
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g.create();
g2.setClip(0, 0, getWidth(), getHeight());
g2.setColor(Color.BLACK);
g2.drawString("FPS: " + fps, 1, 15);
}
public void getFPS()
{
++numFrames;
if (startTime == 0) {
startTime = System.currentTimeMillis();
} else {
long currentTime = System.currentTimeMillis();
long delta = (currentTime - startTime);
if (delta > 1000) {
fps = (numFrames * 1000) / delta;
numFrames = 0;
startTime = currentTime;
}
}
}
}
Thank you!
