Two problems. Flickering despite buffer, and I can't get sizes.
(Code at the end of my post)
I'm new to Java! Heh, so I have decided to set little goals for myself in an attempt to learn common practice and to get a handle on how everything is supposed to work in the language.
I've started working on a little program that makes snowflakes fall down in a window. I use transparent PNG images to save myself some work. Eventually I'd like to use a JPG for a backdrop, but let's not overcomplicate things.
I managed to get flakes falling down, that's easy enough with an image and some threads. Even at different speeds! Wee!
The problem was that they flickered, so aha- double buffering!
I wish.
It doesn't work, and I'm not sure if I'm doing it right and I'd really like to get some overall pointers on my code as well.
Another problem is that I can't seem to get this.WIDTH or this.getWidth to return the width of the window? It always comes back as zero, even when called in addNotify?! What's up with that?
Please, any knowledgeable and kind gurus would be of great help to give me a few badly needed kicks.
(There are three classes, one for my JFrame, one for the scene itself, and one to act as a sorta "individual snowflake")
package snow_flakes;
import java.awt.*;
import javax.swing.*;
publicclass MainFrameextends JFrame{
JPanel contentPane;
BorderLayout borderLayout1 =new BorderLayout();
public MainFrame(){
// Make our program.
try{
setLayout(new BorderLayout());
setDefaultCloseOperation(EXIT_ON_CLOSE);
setSize(new Dimension(600, 350));
setTitle("Snowflakes!");
// Add my little custom snow-scene to the frame.
add(new SnowFlakesScene(), BorderLayout.CENTER);
setVisible(true);
}
// Something big went down in the program.
catch (Exception somethingBig){
somethingBig.printStackTrace();
}
}
publicstaticvoid main(String[] argh){
new MainFrame();
}
}
package snow_flakes;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Point;
import java.awt.Graphics;
import javax.swing.ImageIcon;
import java.awt.Toolkit;
import java.awt.Image;
import javax.swing.JFrame;
publicclass SnowFlakesSceneextends Canvasimplements Runnable{
Thread meThreadded;
Image mySnowFlake;
Image myBuffer;
Toolkit toolKit;
Graphics bufferDraw;
SnowFlake[] sceneFlakes =new SnowFlake[8];
SnowFlakesScene(){
super();
// Set up the toolkit?! WTF is that?
toolKit = Toolkit.getDefaultToolkit();
// Set up the canvas's appearance.
setBackground(new Color(255, 255, 255));
// Set up the snowflakes.
mySnowFlake = toolKit.getImage("snowflake.png");
sceneFlakes[0] =new SnowFlake(this, 15,new Point(0, 0));
sceneFlakes[1] =new SnowFlake(this, 14,new Point(150, 0));
sceneFlakes[2] =new SnowFlake(this, 17,new Point(200, 0));
sceneFlakes[3] =new SnowFlake(this, 9,new Point(95, 0));
sceneFlakes[4] =new SnowFlake(this, 16,new Point(30, 0));
sceneFlakes[5] =new SnowFlake(this, 21,new Point(28, 0));
sceneFlakes[6] =new SnowFlake(this, 19,new Point(15, 0));
sceneFlakes[7] =new SnowFlake(this, 10,new Point(103, 0));
//for(int currentFlake = 0; currentFlake < sceneFlakes.length; currentFlake++) {
//sceneFlakes[currentFlake] = new SnowFlake(this, 1, new Point(0,0));
//}
// Set up the redrawing thread.
meThreadded =new Thread(this);
}
publicvoid addNotify(){
super.addNotify();
// Start the thread once the component is initiated.
meThreadded.start();
// Peer problematic.
myBuffer = createImage(200, 200);
bufferDraw = myBuffer.getGraphics();
System.out.println(this);
}
publicvoid paint(Graphics drawTime){
// Pull the buffer onto the canvas.
drawTime.drawImage(myBuffer, 0, 0,this);
}
// To eliminate flickering.
publicvoid update(){
repaint();
}
publicvoid run(){
while(myBuffer !=null){
try{
bufferDraw.clearRect(0, 0, 200, 200);
for(int currentFlake = 0; currentFlake < sceneFlakes.length; currentFlake++){
bufferDraw.drawImage(mySnowFlake, sceneFlakes[currentFlake].getX(), sceneFlakes[currentFlake].getY(),this);
}
repaint();
// Sleep the minimum amount of time possible.
meThreadded.sleep(1);
}
catch(InterruptedException whoCares){
}
}
}
}
package snow_flakes;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.Point;
publicclass SnowFlakeextends Thread{
// Me honkies.
Image myImage;
SnowFlakesScene myScene;
Point myCoords;
Boolean falling;
// Smaller number, faster fall for flake. Bruhaha!
int myFallSpeed;
// Constructor accepting a string to define the image.
SnowFlake(SnowFlakesScene mySceneSource,int myFallSpeedSource, Point myStartCoords){
myScene = mySceneSource;
//System.out.println("Scene info: " + myScene);
myFallSpeed = myFallSpeedSource;
//System.out.println("Flake fall speed: " + myFallSpeed);
myCoords = myStartCoords;
//System.out.println("Flake starts @: " + myStartCoords);
falling =true;
this.start();
System.out.println("Flake falling.");
}
publicint getX(){
return(myCoords.x);
}
publicint getY(){
return(myCoords.y);
}
publicvoid run(){
while(falling){
// Always move the flake down one.
myCoords.y++;
// Move the flake over left or right, randomly.
try{
sleep(myFallSpeed);
}
catch(InterruptedException whoCares){
}
}
}
}
