java_简易画图板

下面我将分享用Java制作简易画图板的过程。

version 1

Draw.java

import javax.swing.JFrame;

/**
 *
 * @author yangzhenlin
 *
 */
public class Draw extends JFrame {

    public void initDraw() {
        this.setTitle("画图板");
        this.setSize(600, 500);
        this.setDefaultCloseOperation(3);
        this.setVisible(true);

        /**
         * 从窗体上获取画布对象 获取窗体在屏幕上占据的区域，这块区域是允许改变颜色的。
         */
        java.awt.Graphics g = this.getGraphics();

        DrawListener dlis = new DrawListener(g);

        this.addMouseListener(dlis);
    }
}

import javax.swing.JFrame;

/**
 * 
 * @author yangzhenlin
 * 
 */
public class Draw extends JFrame {

	public void initDraw() {
		this.setTitle("画图板");
		this.setSize(600, 500);
		this.setDefaultCloseOperation(3);
		this.setVisible(true);

		/**
		 * 从窗体上获取画布对象 获取窗体在屏幕上占据的区域，这块区域是允许改变颜色的。
		 */
		java.awt.Graphics g = this.getGraphics();

		DrawListener dlis = new DrawListener(g);

		this.addMouseListener(dlis);
	}
}

DrawListener.java

import java.awt.event.MouseEvent;

/**
 *
 * @author yangzhenlin
 *
 */

/**
 * 画板监听器，实现鼠标监听器接口
 */
public class DrawListener implements java.awt.event.MouseListener {
    // private int x1, x2, y1, y2;
    private java.awt.Graphics g;

    public DrawListener(java.awt.Graphics g) {
        this.g = g;
    }

    public void mouseClicked(MouseEvent e) {
        System.out.println("mouseClicked");
    }

    public void mousePressed(MouseEvent e) {
        System.out.println("mousePressed");
    }

    public void mouseReleased(MouseEvent e) {
        System.out.println("mouseReleased");
    }

    public void mouseEntered(MouseEvent e) {
        System.out.println("mouseEntered");
    }

    public void mouseExited(MouseEvent e) {
        System.out.println("mouseExited");
    }

}