Using Thread in Java to Create Animation, Example 5

I said we use the paint() method to have a corner to creat my objects. Further I can have a class for my objects and create images there and bring them on my frame. I need only to pass the graphic of canvas to that class. Then I can even create more than one similar objects on the canvas and put them next together. I can have them resized and rotated and deformed. Now, I use some simple drawings and my aircraft bomber looks more real. I create it in a small sub-class to my canvas. Then I can call it from my paint() method. From this point you can use formalities of object-oriented languages for data encapsulations. But I prefer to experience with animations and put details of software engineering aside until I become fully fluent and in command of more basic details.

package Forward; /** * * author Peter Jones */ public class Ex5Thread extends javax.swing.JFrame implements java.lang.Runnable{ /** Creates new form Ex5Thread */ public Ex5Thread() { super("Example 5!"); // A title for the frame T0=System.currentTimeMillis(); x=X0; y=Y0; aPanel = new javax.swing.JPanel(); setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); setPreferredSize(new java.awt.Dimension(300, 150)); add(aPanel); pack(); start(); } /** Start when browser is loaded or button pushed. **/ public void start() { if (fThread == null){ fThread = new java.lang.Thread (this); fThread.start(); } } // start /** The thread loops to draw each frame.**/ public void run() { //j=0; // Loop through animation frames while ( fThread != null){ // Sleep between frames try{ Thread.sleep (1); t=System.currentTimeMillis()-T0; t=t/1000; //convert to seconds x=(int)(V0*t); y=Y0+(int)(G*t*t/2); paint(); } catch (InterruptedException e) {break; } //break stops the loop // Now go to other frame other(); isDone(); } }// run ends // Your other frame comes here. public void other(){ // // Sleep between frames try{ Thread.sleep (25); aPanel.repaint(); // meanwhile repaint the panel. } catch (InterruptedException e) { } } // Boolean allows you to terminate this thread, // if you like,and go to other tasks. // I used it to provide a flag for counting. public boolean isDone() { boolean temp=false; if(x==300) {//if reaches end of panel temp=true; T0=System.currentTimeMillis();//reset time origin x=X0; //initial x y=Y0; //initial x aPanel.repaint(); //reset the panel } return temp; } //Create some graphic public void paint() { java.awt.Graphics g=aPanel.getGraphics(); // new airCraft().paint(g,x, y, Y0); } public static void main(String args[]) { new Ex5Thread().setVisible(true); } /* Variables declaration - do not modify * For simple GUI * For thread animation */ private javax.swing.JPanel aPanel; private Thread fThread; // Variables declaration - do not modify double t=0; //seconds double T0=0; //seconds int x=0; // X-coordinate of a point final int X0=10; // pixels int y=0; // Y-coordinate of a point final int Y0=30; // pixels final int V0=25; // pixels/second final double G=0.98; //pixels/second/second // End of variables declaration //sub-class creates some graphical object class airCraft{ airCraft(){//Costructor } protected void paint(java.awt.Graphics gr, int x, int y, int Y){ gr.setColor(java.awt.Color.green); gr.fillOval(x, Y+10, 100, 20);//fuselage gr.setColor(java.awt.Color.red); gr.fillArc(x-20, Y+5, 40, 20, 0, 100);//tail gr.fillArc(x+10, Y+3, 60, 15, 0, 135);//far wing gr.fillArc(x+35, Y+10, 35, 20, 0, -135);//front wing gr.setColor(java.awt.Color.gray); gr.fillArc(x+55, Y+10, 40, 10, 0, 100);//cockpit gr.fillOval(x+30, Y+y, 10, 5);//bomb } } }

Click here to see the application. If you save the "jar" file in your computer you can use "7z" decompression utility to extract source file and image files.