Question

该程序为条形图绘制了一堆矩形。我知道吧类的工作非常好，因为我在添加图表面板类之前已经完成了它。我正在直接画到框架而不是图形面板。我认为我的set可见方法被调用的方式存在问题，因为之前曾向我指出过。我试着调查一下但是在玩完并阅读文档之后我没有运气。

     import java.awt.Color;
    import java.util.ArrayList;
    import java.util.Random;
    import javax.swing.JFrame;
    import javax.swing.JPanel;
    import java.awt.Graphics;
    import java.awt.Graphics2D;
    import java.awt.Rectangle;
    import java.util.concurrent.Semaphore;

@SuppressWarnings("serial")
public class GraphPanel extends JPanel {

    private ArrayList<Bar> graphBars;
    private int nBars;

    public GraphPanel(int nBars, JFrame mainFrame) {
        this.setSize(400, 400);
        this.graphBars = new ArrayList<Bar>(nBars);
        this.nBars = nBars;
        this.initBars(mainFrame.getWidth());
        for(Bar b: this.graphBars) {
            this.add(b);
        }

    }

    private void initBars(int frameW) {
        Random random = new Random();
        float hue; 
        Color color; 
        int barPadding = frameW/this.nBars;
        for(int i = 0; i < this.nBars; i++) {
            hue = random.nextFloat();
            color = Color.getHSBColor(hue, 0.9f, 1.0f);
            this.graphBars.add(new Bar(i*barPadding + 30, 350, color));
        }
    }

    public ArrayList<Bar> getBarList() {
        return this.graphBars;
    }
}






@SuppressWarnings("serial")
public class Bar extends JPanel implements Runnable {

    int height = 0;
    Color barColor;
    Rectangle bar;
    private final int WIDTH = 20;
    Thread bartender;
    private Semaphore s;

    public Bar(int x, int y, Color barColor) {
        this.barColor= barColor;
        this.bar = new Rectangle(x, y, this.WIDTH, this.height);
        this.bartender= new Thread(this);
        this.s = new Semaphore(1);
    }

    public boolean setNewHeight(int h) {
        try {
            this.s.acquire();
            this.height = h;
            this.s.release();
            return true;
        } catch (InterruptedException e) {
            e.printStackTrace();
            return false;
        }
    }

    @SuppressWarnings("deprecation")
    public void update() {
        if (this.bar.height < this.height) {
            bar.reshape(this.bar.x, --this.bar.y, this.bar.width, ++this.bar.height);
        } else {
            bar.reshape(this.bar.x, ++this.bar.y, this.bar.width, --this.bar.height);
        }
    }

    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        Graphics2D g2d = (Graphics2D) g.create();
        g2d.setColor(this.barColor);
        g2d.fill(this.bar);
    }

    @SuppressWarnings("deprecation")
    public void callBarTender() {
        this.bartender.resume();
    }

    @SuppressWarnings("deprecation")
    @Override
    public void run() {
        System.out.println("sdf");
        while(true) {
            if (this.bar.height < this.height) {
                for(int i = this.bar.height; i<this.height; i++ ) {
                    try {
                        update();
                        repaint();
                        Thread.sleep(15);
                    } catch(Exception e) {
                        System.out.println(e);
                    }
                }
            } else if (this.height < this.bar.height) {
                for(int i = this.bar.height; i>this.height; i-- ) {
                    try {
                        update();
                        repaint();
                        Thread.sleep(15);
                    } catch(Exception e) {
                        System.out.println(e);
                    }
                }
            }
            this.bartender.suspend();
        }
    }

}



 public static void main(String[] args) {
            JFrame frame = new JFrame();
            frame.setSize(400, 400);
            frame.setResizable(false);
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

            GraphPanel gPane = new GraphPanel(3, frame);
            frame.add(gPane);

            gPane.getBarList().get(0).setVisible(true);
            gPane.getBarList().get(1).setVisible(true);
            gPane.getBarList().get(2).setVisible(true);
            gPane.setVisible(true);
            frame.setVisible(true);

            gPane.getBarList().get(0).setNewHeight(100);
            gPane.getBarList().get(1).setNewHeight(100);
            gPane.getBarList().get(2).setNewHeight(100);

            gPane.getBarList().get(0).bartender.start();
            gPane.getBarList().get(1).bartender.start();
            gPane.getBarList().get(2).bartender.start();
    }

Answer 1

您应该覆盖getPreferredSize的{{1}}以确保它们的布局正确
您传递给GraphPanel类的x / y位置无关紧要，因为这会导致Bar在Rectangle窗格的可见上下文之外绘制。绘画是在组件的上下文中完成的（0x0是组件的顶部/左角）
使用Bar或您使用它的方式实际上会导致问题。在组件铺设或涂漆之前，不可能确切知道组件的大小。
有一个原因导致Rectangle和resume被弃用，这可能会导致“＃34;奇怪的”＃34; （和精彩）问题
请查看Laying Out Components Within a Container，了解为什么您的酒吧未正确更新以及为什么x / y坐标毫无意义
请使用How to use Swing Timers查看您使用suspend

可能更像是......

Bars

Thread

java图形不是绘制任何东西

1 个答案: