Java：製作一個漂亮的JProgressBar

Question

我一直在使用JProgressBars在java中的時間不長，並且我所看到的將它設置爲漂亮的每個資源都不起作用。我想要的是在應用程序中，您將看到從上到下填充的整個進度欄，並且當值增加時，動畫會隨着大小的增加而變化。我現在已經是一個JProgressBar，當它增加價值，它沒有動畫，當它的偏移轉到右上角，就像這樣：

正如你所看到的，它很醜。我怎樣才能看到完整的邊框，整個填充和動畫到JProgressBar？

Answer 1

關於你可以以任何有意義的方式修改JProgressBar將設計自己的UI委託的唯一途徑...

這基本上是基於一些工作一個例子，我做了一個很長過去。

示例以25爲增量更新進度欄，但進度欄「嘗試」以小增量從當前位置填充到目標值。

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.GridBagLayout; 
import java.awt.LinearGradientPaint; 
import java.awt.RenderingHints; 
import java.awt.event.ActionEvent; 
import java.awt.event.ActionListener; 
import java.awt.geom.Point2D; 
import java.awt.geom.RoundRectangle2D; 
import javax.swing.BoundedRangeModel; 
import javax.swing.JComponent; 
import javax.swing.JFrame; 
import javax.swing.JPanel; 
import javax.swing.JProgressBar; 
import javax.swing.Timer; 
import javax.swing.UIManager; 
import javax.swing.UnsupportedLookAndFeelException; 
import javax.swing.event.ChangeEvent; 
import javax.swing.event.ChangeListener; 
import javax.swing.plaf.basic.BasicProgressBarUI; 

public class TestMediaProgressBar { 

    public static void main(String[] args) { 
     new TestMediaProgressBar(); 
    } 

    public TestMediaProgressBar() { 
     EventQueue.invokeLater(new Runnable() { 
      @Override 
      public void run() { 
       try { 
        UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); 
       } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) { 
       } 

       JFrame frame = new JFrame("Testing"); 
       frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
       frame.add(new TestPane()); 
       frame.pack(); 
       frame.setLocationRelativeTo(null); 
       frame.setVisible(true); 
      } 
     }); 
    } 

    public class TestPane extends JPanel { 

     private MediaProgressBar pb; 
     private int value = 0; 
     private int delta = 25; 

     public TestPane() { 
      setBackground(Color.BLACK); 
      setLayout(new GridBagLayout()); 
      pb = new MediaProgressBar(); 
      add(pb); 

      Timer timer = new Timer(500, new ActionListener() { 
       @Override 
       public void actionPerformed(ActionEvent e) { 
        if (value + delta > 100) { 
         delta *= -1; 
         value = 100; 
        } else if (value + delta < 0) { 
         delta *= -1; 
         value = 0; 
        } 
        value += delta; 
        pb.setValue(value); 
       } 
      }); 
      timer.start(); 
     } 

     @Override 
     public Dimension getPreferredSize() { 
      return new Dimension(200, 200); 
     } 
    } 

    public class MediaProgressBar extends JProgressBar { 

     public MediaProgressBar() { 
      setUI(new MediaProgressBarUI()); 
     } 

     @Override 
     public Dimension getPreferredSize() { 

      return new Dimension(128, 24); 

     } 

    } 

    public class MediaProgressBarUI extends BasicProgressBarUI { 

     private Handler handler; 
     private double renderProgress = 0; 
     private double targetProgress = 0; 
     private double progressDelta = 0.04; 
     private Timer repaintTimer; 
     private Timer paintTimer; 

     public MediaProgressBarUI() { 
      repaintTimer = new Timer(25, new ActionListener() { 
       @Override 
       public void actionPerformed(ActionEvent e) { 
        progressBar.repaint(); 
       } 
      }); 
      repaintTimer.setRepeats(false); 
      repaintTimer.setCoalesce(true); 

      paintTimer = new Timer(40, new ActionListener() { 
       @Override 
       public void actionPerformed(ActionEvent e) { 
        if (progressDelta < 0) { 

         if (renderProgress + progressDelta < targetProgress) { 
          ((Timer) e.getSource()).stop(); 
          renderProgress = targetProgress + progressDelta; 
         } 

        } else { 

         if (renderProgress + progressDelta > targetProgress) { 
          ((Timer) e.getSource()).stop(); 
          renderProgress = targetProgress - progressDelta; 
         } 

        } 
        renderProgress += progressDelta; 
        requestRepaint(); 
       } 
      }); 
     } 

     protected void requestRepaint() { 
      repaintTimer.restart(); 
     } 

     @Override 
     protected void installDefaults() { 
      super.installDefaults(); 
      progressBar.setOpaque(false); 
      progressBar.setBorder(null); 
     } 

     public void setRenderProgress(double value) { 
      if (value != targetProgress) { 
       paintTimer.stop(); 

       targetProgress = value; 
       if (targetProgress < renderProgress && progressDelta > 0) { 
        progressDelta *= -1; 
       } else if (targetProgress > renderProgress && progressDelta < 0) { 
        progressDelta *= -1; 
       } 
       System.out.println(progressDelta); 

       paintTimer.start(); 
      } 
     } 

     public double getRenderProgress() { 
      return renderProgress; 
     } 

     @Override 
     public void paint(Graphics g, JComponent c) { 
      Graphics2D g2d = (Graphics2D) g.create(); 

      g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); 

      int iStrokWidth = 3; 
      g2d.setStroke(new BasicStroke(iStrokWidth, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND)); 
      g2d.setColor(c.getBackground()); 
      g2d.setBackground(c.getBackground()); 

      int width = c.getWidth(); 
      int height = c.getHeight(); 

      RoundRectangle2D outline = new RoundRectangle2D.Double((iStrokWidth/2), (iStrokWidth/2), 
        width - iStrokWidth, height - iStrokWidth, 
        height, height); 

      g2d.draw(outline); 

      int iInnerHeight = height - (iStrokWidth * 4); 
      int iInnerWidth = width - (iStrokWidth * 4); 

      iInnerWidth = (int) Math.round(iInnerWidth * renderProgress); 

      int x = iStrokWidth * 2; 
      int y = iStrokWidth * 2; 

      Point2D start = new Point2D.Double(x, y); 
      Point2D end = new Point2D.Double(x, y + iInnerHeight); 

      float[] dist = {0.0f, 0.25f, 1.0f}; 
      Color[] colors = {c.getBackground(), c.getBackground().brighter(), c.getBackground().darker()}; 
      LinearGradientPaint p = new LinearGradientPaint(start, end, dist, colors); 

      g2d.setPaint(p); 

      RoundRectangle2D fill = new RoundRectangle2D.Double(iStrokWidth * 2, iStrokWidth * 2, 
        iInnerWidth, iInnerHeight, iInnerHeight, iInnerHeight); 

      g2d.fill(fill); 

      g2d.dispose(); 
     } 

     @Override 
     protected void installListeners() { 
      super.installListeners(); 
      progressBar.addChangeListener(getChangeHandler()); 
     } 

     protected ChangeListener getChangeHandler() { 

      return getHandler(); 

     } 

     protected Handler getHandler() { 

      if (handler == null) { 
       handler = new Handler(); 
      } 

      return handler; 

     } 

     protected class Handler implements ChangeListener { 

      @Override 
      public void stateChanged(ChangeEvent e) { 

       BoundedRangeModel model = progressBar.getModel(); 
       int newRange = model.getMaximum() - model.getMinimum(); 
       double dProgress = (double) (model.getValue()/(double) newRange); 

       if (dProgress < 0) { 
        dProgress = 0; 
       } else if (dProgress > 1) { 
        dProgress = 1; 
       } 

       setRenderProgress(dProgress); 

      } 

     } 

    } 

}