canvas.java

介绍有关java的资料 课件 相当一本书籍 里面都是很基础的知识

		import java.awt.*;
		import java.applet.Applet;
		public class canvas extends Applet {
			Button b1;
                        TextField xValue;
                        TextField yValue;
			public void init() {
				setLayout(new BorderLayout(15,15));
				b1 = new Button("Test");
                                xValue = new TextField("0",5);
                                yValue = new TextField("0",5);
				myCanvas c1 = new myCanvas(100,100);
				add("Center",c1);
				add("South",b1);
                                add("East",xValue);
                                add("West",yValue);
			}
			public boolean action(Event e, Object arg) {
                                TextField xValue = new TextField("0",5);
                                TextField yValue = new TextField("0",5);
				//System.out.println("Event: " + arg);
                                xValue.setText("Event: " + arg);
                                yValue.setText("y");
				return true;
			}
			public boolean mouseDown(Event e, int x, int y) {
				System.out.println("Mouse works: (" + x + "," + y + ")");
				return true;
			}
		}
		class myCanvas extends Canvas {
			private int width;
			private int height;
			public myCanvas(int w,int h) {
				width = w;
				height = h;
				reshape(0,0,w,h);
			}
			public void paint(Graphics g) {
				g.setColor(Color.blue);
				g.fillRect(0, 0, width, height);
			}
			public boolean mouseDown(Event e, int x, int y) {
                                TextField xValue = new TextField("0",5);
                                TextField yValue = new TextField("0",5);
				if (( x < width) && (y <height)) {
					xValue.setText(Integer.toString(x));
                                        yValue.setText(Integer.toString(y));
					return true;					//有鼠标按下
				}
				return false;						//没有鼠标按下
			}
		}