JAVA Swing自定义JScorllPanel

JAVA Swing中JScrollPanle自定义带标尺的JScrollPanel

Swing中JScrollPanel的结构与组成如下图：

分为四个角与四个边，中间蓝色矩形为View窗口，可以通过调用JScrollPanel的

getViewport().setView(view)完成对现实内容的设置。

最常见的自定义JScrollPanel是改写默认的Column  Header View与Row Header View

下面是我做的一个关于瓷砖排列显示的UI，实现了一个标尺化的JScrollPanel，可以很好

的度量与说明空间大小与瓷砖需求的关系，实现效果如下：

自定义的列与行标尺View的代码如下：

package com.gloomyfish.swing.custom.ui; 
      
import java.awt.Color; 
import java.awt.Dimension; 
import java.awt.Graphics; 
import java.awt.Graphics2D; 
import java.awt.geom.Line2D; 
import java.awt.geom.Rectangle2D; 
      
import javax.swing.JComponent; 
      
public class RuleView extends JComponent { 
    /**
     * 
     */ 
    private static final long serialVersionUID = 1L; 
    public static final int HORIZONTAL = 0; 
    public static final int VERTICAL = 1; 
    private int SIZE = 600; 
    public int orientation; 
    public boolean isMetric; 
    private double increment; 
    private double units; 
    private int width; 
    private int height; 
          
    public RuleView(int o, boolean m) { 
        orientation = o; 
        isMetric = m; 
        setIncrementAndUnits(); 
        if(orientation == HORIZONTAL) 
        { 
            width = SIZE; 
        } 
        else 
        { 
            height = SIZE; 
        } 
    } 
      
    private void setIncrementAndUnits() { 
              
    } 
          
    public void setPreferredHeight(int ph) { 
        this.height = ph; 
        setPreferredSize(new Dimension(SIZE, ph)); 
    } 
      
    public void setPreferredWidth(int pw) { 
        this.width = pw; 
        setPreferredSize(new Dimension(pw, SIZE)); 
    } 
      
    protected void paintComponent(Graphics g) { 
        Graphics2D g2d = (Graphics2D) g; 
        System.out.println("width = " + width); 
        System.out.println("Height = " + height); 
              
        // background color 
        g2d.setColor(new Color(102, 255, 255)); 
        Rectangle2D rect2d = new Rectangle2D.Double(0, 0, width, height); 
        g2d.fill(rect2d); 
              
              
        int count = 0; 
        increment = 0; 
              
        // unit and text symbol 
        g2d.setPaint(new Color(0,0,204)); 
        if(orientation == HORIZONTAL) 
        { 
            units = width / 10.0; 
            for(int i=0; i<=units; i++) 
            { 
                double rowOff = i * 10.0; 
                Line2D line = new Line2D.Double(rowOff, height*0.7, rowOff, height); 
                g2d.draw(line); 
                if(count == 10) 
                { 
                    count = 0; 
                    increment += 1; 
                    Line2D bigLine = new Line2D.Double(rowOff, height*0.4, rowOff, height); 
                    g2d.draw(bigLine); 
                    g2d.drawString(increment + "", (int)rowOff-3, (int)(height/3.0)); 
                } 
                count++; 
            } 
        } 
        else 
        { 
            units = height / 10.0; 
            for(int i=0; i<=units; i++) 
            { 
                double colOff = i * 10.0; 
                Line2D line = new Line2D.Double(width*0.7, colOff, width, colOff); 
                g2d.draw(line); 
                if(count == 10) 
                { 
                    count = 0; 
                    increment += 1; 
                    Line2D bigLine = new Line2D.Double(width*0.5, colOff, width, colOff); 
                    g2d.draw(bigLine); 
                    g2d.drawString(increment + "", 0, (int)colOff); 
                } 
                count++; 
            } 
        } 
        g2d.setPaint(Color.RED); 
              
    } 
}

自定义的JScrollPanel的代码如下：

package com.gloomyfish.swing.custom.ui; 
    
import java.awt.Color; 
import java.awt.FlowLayout; 
import java.awt.Font; 
    
import javax.swing.JComponent; 
import javax.swing.JLabel; 
import javax.swing.JPanel; 
import javax.swing.JScrollPane; 
import javax.swing.border.LineBorder; 
    
public class JCustomScrollPane extends JScrollPane { 
    
    /**
     * 
     */ 
    private static final long serialVersionUID = 1L; 
    private RuleView columnView; 
    private RuleView rowView; 
    private JLabel cornerLabel; 
    public JCustomScrollPane(int rowSize, int columnSize) 
    { 
        super(); 
        JPanel buttonCorner = new JPanel(); // use FlowLayout 
        cornerLabel = new JLabel("单位:米"); 
        cornerLabel.setForeground(Color.BLUE); 
        cornerLabel.setFont(new Font("Serif", Font.PLAIN, 8)); 
        buttonCorner.setLayout(new FlowLayout(FlowLayout.LEFT)); 
        buttonCorner.add(cornerLabel); 
        setCorner(JScrollPane.UPPER_LEFT_CORNER, buttonCorner); 
        columnView = new RuleView(RuleView.HORIZONTAL, true); 
        columnView.setPreferredHeight(30); 
        rowView = new RuleView(RuleView.VERTICAL, true); 
        rowView.setPreferredWidth(30); 
        setColumnHeaderView(columnView); 
        setRowHeaderView(rowView); 
        setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS); 
        setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS); 
        setViewportBorder(new LineBorder(Color.RED)); 
    } 
        
    public void setImagePanel(JComponent view) 
    { 
        this.getViewport().setView(view); 
    } 
        
}

最后说一下，Swing 是非常灵活的UI组件，提供了非常多的自定义接口

怎么合理运用就看个人啦！