Lesson9

[admin]

Create the project DrawingApp.

[admin]

1. package drawingapp;
2. import org.opensourcephysics.controls.*;
3. import org.opensourcephysics.display.*;
4. import org.opensourcephysics.frames.*;
5. public class DrawingApp extends AbstractCalculation {
6. DisplayFrame frame = new DisplayFrame("x", "y", "Graphics");
7. public DrawingApp() {
8. frame.setPreferredMinMax(0, 10, 0, 10);
9. }
10. public void calculate() {
11. // gets rectangle location
12. int left = control.getInt("xleft");
13. int top = control.getInt("ytop");
14. // gets rectangle dimensions
15. int width = control.getInt("width");
16. int height = control.getInt("height");
17. Drawable rectangle = new PixelRectangle(left, top, width, height);
18. frame.addDrawable(rectangle);
19. // frame is automatically rendered after Calculate button is pressed
20. }
21. public void reset() {
22. frame.clearDrawables(); // removes drawables added by the user
23. control.setValue("xleft", 60); // sets default input values
24. control.setValue("ytop", 70);
25. control.setValue("width", 100);
26. control.setValue("height", 150);
27. }
28. public static void main(String[] args) { // creates a calculation control structure using this class
29. CalculationControl.createApp(new DrawingApp());
30. }
31. }

[admin]

Code: Select all

package drawingapp;
import org.opensourcephysics.controls.*;
import org.opensourcephysics.display.*;
import org.opensourcephysics.frames.*;
public class DrawingApp extends AbstractCalculation {
  DisplayFrame frame = new DisplayFrame("x", "y", "Graphics");
  public DrawingApp() {
    frame.setPreferredMinMax(0, 10, 0, 10);
  }
  public void calculate() {
    // gets rectangle location
    int left = control.getInt("xleft");
    int top = control.getInt("ytop");
    // gets rectangle dimensions
    int width = control.getInt("width");
    int height = control.getInt("height");
    Drawable rectangle = new PixelRectangle(left, top, width, height);
    frame.addDrawable(rectangle);
    // frame is automatically rendered after Calculate button is pressed
  }
  public void reset() {
    frame.clearDrawables();        // removes drawables added by the user
    control.setValue("xleft", 60); // sets default input values
    control.setValue("ytop", 70);
    control.setValue("width", 100);
    control.setValue("height", 150);
  }
  public static void main(String[] args) { // creates a calculation control structure using this class
    CalculationControl.createApp(new DrawingApp());
  }
}

[admin]

Add the file PixelRectangle (java application) to the project.
Add osp.jar to the project.

[admin]

1. package drawingapp;
2. import java.awt.*; // uses Abstract Window Toolkit (awt)
3. import org.opensourcephysics.display.*;
4. public class PixelRectangle implements Drawable {
5. int left, top; // position of rectangle in pixels
6. int width, height; // size of rectangle in pixels
7. PixelRectangle(int left, int top, int width, int height) {
8. this.left = left; // location of left edge
9. this.top = top; // location of top edge
10. this.width = width;
11. this.height = height;
12. }
13. public void draw(DrawingPanel panel, Graphics g) {
14. // this method implements the Drawable interface
15. g.setColor(Color.RED); // set drawing color to red
16. g.fillRect(left, top, width, height); // draws rectangle
17. }
18. }

[admin]

Code: Select all

package drawingapp;
import java.awt.*; // uses Abstract Window Toolkit (awt)
import org.opensourcephysics.display.*;
public class PixelRectangle implements Drawable {
  int left, top;     // position of rectangle in pixels
  int width, height; // size of rectangle in pixels
  PixelRectangle(int left, int top, int width, int height) {
    this.left = left; // location of left edge
    this.top = top;   // location of top edge
    this.width = width;
    this.height = height;
  }
  public void draw(DrawingPanel panel, Graphics g) {
    // this method implements the Drawable interface
    g.setColor(Color.RED);                // set drawing color to red
    g.fillRect(left, top, width, height); // draws rectangle
  }
}

[admin]

The screenshot of DrawingApp program.