Java 逐步在JPanel上绘图
我想创建一个Java 逐步在JPanel上绘图,java,multithreading,swing,jframe,jpanel,Java,Multithreading,Swing,Jframe,Jpanel,我想创建一个JPanel并在上面一个接一个地画东西。我希望看到他们相互补充。问题是,我总是要等到一切都通过paintComponent方法完成。有没有办法实现我的愿望?提前谢谢 package javapaintui; import java.awt.*; import java.util.logging.Level; import java.util.logging.Logger; import javax.swing.*; class JavaPaintUI extends JFrame
JPanel
并在上面一个接一个地画东西。我希望看到他们相互补充。问题是,我总是要等到一切都通过paintComponent
方法完成。有没有办法实现我的愿望?提前谢谢
package javapaintui;
import java.awt.*;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.*;
class JavaPaintUI extends JFrame {
private JPanel jPanel2;
public JavaPaintUI() {
initComponents();
}
private void initComponents() {
jPanel2 = new Panel2();
this.setContentPane(jPanel2);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
pack();
}
class Panel2 extends JPanel {
Panel2() {
setPreferredSize(new Dimension(420, 420));
}
@Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawString("BLAH", 20, 20);
try {
Thread.sleep(5000);
} catch (InterruptedException ex) {
Logger.getLogger(JavaPaintUI.class.getName()).log(Level.SEVERE, null, ex);
}
g.drawRect(200, 200, 200, 200);
}
}
public static void main(String args[]) {
EventQueue.invokeLater(new Runnable() {
public void run() {
new JavaPaintUI().setVisible(true);
}
});
}
}
永远不要在Swing应用程序的事件调度线程中使用
Thread.sleep(…)
。当您将paintComponent方法置于睡眠状态时,它的正确性是100倍。解决方法是使用摆动计时器
e、 g
import java.awt.BasicStroke;
导入java.awt.Color;
导入java.awt.Dimension;
导入java.awt.EventQueue;
导入java.awt.Graphics;
导入java.awt.Graphics2D;
导入java.awt.Rectangle;
导入java.awt.RenderingHints;
导入java.awt.Shape;
导入java.awt.Stroke;
导入java.awt.event.ActionEvent;
导入java.awt.event.ActionListener;
导入java.util.ArrayList;
导入java.util.List;
导入java.util.Random;
导入javax.swing.*;
类JavaPaintUI扩展了JFrame{
专用静态最终颜色填充颜色=Color.BLUE;
私有静态最终颜色边框\u Color=Color.RED;
公共静态最终冲程=新基本冲程(4f);
私人JPanel jPanel2;
公共JavaPaintUI(){
初始化组件();
}
私有组件(){
jPanel2=新面板2();
这个.setContentPane(jPanel2);
此.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
包装();
}
类Panel2扩展了JPanel{
专用静态最终int定时器_延迟=2000;
私有随机=新随机();
私有列表shapeList=new ArrayList();
小组2(){
setPreferredSize(新尺寸(420420));
新计时器(计时器延迟,新ActionListener(){
@凌驾
已执行的公共无效操作(操作事件evt){
int width=random.nextInt(100);
整数高度=随机。下一个整数(100);
int x=random.nextInt(getWidth()-width);
int y=random.nextInt(getHeight()-height);
添加(新矩形(x,y,宽度,高度));
重新油漆();
}
}).start();
}
@凌驾
公共组件(图形g){
超级组件(g);
g、 抽绳(“废话”,20,20);
图形2d g2=(图形2d)g;
g2.setRenderingHint(RenderingHints.KEY_抗锯齿,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.设定行程(行程);
用于(形状:形状列表){
g2.设置颜色(填充颜色);
g2.填充(形状);
g2.设置颜色(边框颜色);
g2.绘制(形状);
}
}
}
公共静态void main(字符串参数[]){
invokeLater(新的Runnable(){
公开募捐{
新建JavaPaintUI().setVisible(true);
}
});
}
}
编辑
你问: 现在的问题是,我打算画一棵二叉树。绘图机制是这样工作的:我将树的根传递给绘图函数,绘图函数将遍历它,并在面板上绘制一棵树。我使用drawString、drawOval和drawLine函数,这种方法似乎很难实现。你有解决办法吗
事实上,我已经给了你一个完美的解决方案。shapeList
List
变量将接受实现Shape
接口的任何内容,这意味着您可以向其中添加Line2D、Ellipse2D和类似对象 永远不要在Swing应用程序的事件调度线程中使用Thread.sleep(…)
。当您将paintComponent方法置于睡眠状态时,它的正确性是100倍。解决方法是使用摆动计时器
e、 g
import java.awt.BasicStroke;
导入java.awt.Color;
导入java.awt.Dimension;
导入java.awt.EventQueue;
导入java.awt.Graphics;
导入java.awt.Graphics2D;
导入java.awt.Rectangle;
导入java.awt.RenderingHints;
导入java.awt.Shape;
导入java.awt.Stroke;
导入java.awt.event.ActionEvent;
导入java.awt.event.ActionListener;
导入java.util.ArrayList;
导入java.util.List;
导入java.util.Random;
导入javax.swing.*;
类JavaPaintUI扩展了JFrame{
专用静态最终颜色填充颜色=Color.BLUE;
私有静态最终颜色边框\u Color=Color.RED;
公共静态最终冲程=新基本冲程(4f);
私人JPanel jPanel2;
公共JavaPaintUI(){
初始化组件();
}
私有组件(){
jPanel2=新面板2();
这个.setContentPane(jPanel2);
此.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
包装();
}
类Panel2扩展了JPanel{
专用静态最终int定时器_延迟=2000;
私有随机=新随机();
私有列表shapeList=new ArrayList();
小组2(){
setPreferredSize(新尺寸(420420));
新计时器(计时器延迟,新ActionListener(){
@凌驾
已执行的公共无效操作(操作事件evt){
int width=random.nextInt(100);
整数高度=随机。下一个整数(100);
int x=random.nextInt(getWidth()-width);
int y=random.nextInt(getHeight()-height);
添加(新矩形(x,y,宽度,高度));
重新油漆();
}
}).start();
}
@凌驾
公共组件(图形g){
超级组件(g);
g、 抽绳(“废话”,20,20);
图形2d g2=(图形2d)g;
g2.setRenderingHint(RenderingHints.KEY_抗锯齿,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.设定行程(行程);
用于(形状:形状列表){
g2.设置颜色(填充颜色);
g2.填充(形状);
g2.设置颜色(边框颜色);
g2.绘制(形状);
}
}
}
公共静态voi
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.RenderingHints;
import java.awt.Shape;
import java.awt.Stroke;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import javax.swing.*;
class JavaPaintUI extends JFrame {
private static final Color FILL_COLOR = Color.BLUE;
private static final Color BORDER_COLOR = Color.RED;
public static final Stroke STROKE = new BasicStroke(4f);
private JPanel jPanel2;
public JavaPaintUI() {
initComponents();
}
private void initComponents() {
jPanel2 = new Panel2();
this.setContentPane(jPanel2);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
pack();
}
class Panel2 extends JPanel {
private static final int TIMER_DELAY = 2000;
private Random random = new Random();
private List<Shape> shapeList = new ArrayList<>();
Panel2() {
setPreferredSize(new Dimension(420, 420));
new Timer(TIMER_DELAY, new ActionListener() {
@Override
public void actionPerformed(ActionEvent evt) {
int width = random.nextInt(100);
int height = random.nextInt(100);
int x = random.nextInt(getWidth() - width);
int y = random.nextInt(getHeight() - height);
shapeList.add(new Rectangle(x, y, width, height));
repaint();
}
}).start();
}
@Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawString("BLAH", 20, 20);
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.setStroke(STROKE);
for (Shape shape : shapeList) {
g2.setColor(FILL_COLOR);
g2.fill(shape);
g2.setColor(BORDER_COLOR);
g2.draw(shape);
}
}
}
public static void main(String args[]) {
EventQueue.invokeLater(new Runnable() {
public void run() {
new JavaPaintUI().setVisible(true);
}
});
}
}