Java - 如何在JFrame中的IDE生成的JPanel上绘制形状

Question

我正在使用NetBeans IDE来编写GUI应用程序。它将计算各种原始2D/3D形状的面积/体积。 我在里面创建了一个新的JFrame - JTabbedPane，它有2D和3D形状的两个选项卡。

我打算为每个形状的选项卡创建自定义jpegs，这不是问题，但我不能在形状类型选项卡内绘制形状（请参见图片）。

只有一个.java文件，我粘贴在这里的内容。请帮助我，我非常困惑，我该如何解决这个问题。

// @author Žanas Stundys 
package geometrinis.projektas; 
import java.awt.*; 
import java.awt.event.*; 
import javax.swing.*; 

// 
public class PagrindinisLangas extends javax.swing.JFrame { 


/* Creates new form PagrindinisLangas */ 
public PagrindinisLangas() { 
    initComponents(); 

} 
// 
/* This method is called from within the constructor to initialize the form */ 
//@SuppressWarnings("unchecked") 
// <editor-fold defaultstate="collapsed" desc="Generated Code">       
private void initComponents() { 

    jScrollPane1 = new javax.swing.JScrollPane(); 
    jEditorPane1 = new javax.swing.JEditorPane(); 
    jTabbedPane1 = new javax.swing.JTabbedPane(); 
    jPanel1 = new javax.swing.JPanel(); 
    jTabbedPane2 = new javax.swing.JTabbedPane(); 
    jPanel3 = new javax.swing.JPanel(); 
    jPanel4 = new javax.swing.JPanel(); 
    jPanel2 = new javax.swing.JPanel(); 

    jScrollPane1.setViewportView(jEditorPane1); 

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); 
    setCursor(new java.awt.Cursor(java.awt.Cursor.DEFAULT_CURSOR)); 
    setResizable(false); 
    setSize(new java.awt.Dimension(960, 480)); 

    jTabbedPane1.setToolTipText(""); 

    jTabbedPane2.setTabPlacement(javax.swing.JTabbedPane.LEFT); 

    javax.swing.GroupLayout jPanel3Layout = new javax.swing.GroupLayout(jPanel3); 
    jPanel3.setLayout(jPanel3Layout); 
    jPanel3Layout.setHorizontalGroup(
     jPanel3Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
     .addGap(0, 0, Short.MAX_VALUE) 
    ); 
    jPanel3Layout.setVerticalGroup(
     jPanel3Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
     .addGap(0, 0, Short.MAX_VALUE) 
    ); 

    jTabbedPane2.addTab("", new javax.swing.ImageIcon(getClass().getResource("/Assets/2D/square.png")), jPanel3, "Kvadratas/Stačiakampis"); // NOI18N 

    javax.swing.GroupLayout jPanel4Layout = new javax.swing.GroupLayout(jPanel4); 
    jPanel4.setLayout(jPanel4Layout); 
    jPanel4Layout.setHorizontalGroup(
     jPanel4Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
     .addGap(0, 0, Short.MAX_VALUE) 
    ); 
    jPanel4Layout.setVerticalGroup(
     jPanel4Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
     .addGap(0, 0, Short.MAX_VALUE) 
    ); 

    jTabbedPane2.addTab("", new javax.swing.ImageIcon(getClass().getResource("/Assets/2D/circle.png")), jPanel4, "Apskritimas"); // NOI18N 

    javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1); 
    jPanel1.setLayout(jPanel1Layout); 
    jPanel1Layout.setHorizontalGroup(
     jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
     .addGroup(jPanel1Layout.createSequentialGroup() 
      .addContainerGap() 
      .addComponent(jTabbedPane2, javax.swing.GroupLayout.PREFERRED_SIZE, 876, javax.swing.GroupLayout.PREFERRED_SIZE) 
      .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)) 
    ); 
    jPanel1Layout.setVerticalGroup(
     jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
     .addGroup(jPanel1Layout.createSequentialGroup() 
      .addContainerGap() 
      .addComponent(jTabbedPane2, javax.swing.GroupLayout.PREFERRED_SIZE, 387, javax.swing.GroupLayout.PREFERRED_SIZE) 
      .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)) 
    ); 

    jTabbedPane1.addTab("2D", new javax.swing.ImageIcon(getClass().getResource("/Assets/icon2d.png")), jPanel1); // NOI18N 

    javax.swing.GroupLayout jPanel2Layout = new javax.swing.GroupLayout(jPanel2); 
    jPanel2.setLayout(jPanel2Layout); 
    jPanel2Layout.setHorizontalGroup(
     jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
     .addGap(0, 0, Short.MAX_VALUE) 
    ); 
    jPanel2Layout.setVerticalGroup(
     jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
     .addGap(0, 0, Short.MAX_VALUE) 
    ); 

    jTabbedPane1.addTab("3D", new javax.swing.ImageIcon(getClass().getResource("/Assets/icon3d.png")), jPanel2, ""); // NOI18N 

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); 
    getContentPane().setLayout(layout); 
    layout.setHorizontalGroup(
     layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
     .addComponent(jTabbedPane1, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, 960, Short.MAX_VALUE) 
    ); 
    layout.setVerticalGroup(
     layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
     .addComponent(jTabbedPane1, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, 480, Short.MAX_VALUE) 
    ); 

    pack(); 
}// </editor-fold>       

/* @param args the command line arguments */ 
public static void main(String args[]){ 
    /* Create and display the form */ 

    java.awt.EventQueue.invokeLater(() -> { 
     new PagrindinisLangas().setVisible(true); 
    }); 

} 
// Variables declaration - do not modify      
private javax.swing.JEditorPane jEditorPane1; 
private javax.swing.JPanel jPanel1; 
private javax.swing.JPanel jPanel2; 
private javax.swing.JPanel jPanel3; 
private javax.swing.JPanel jPanel4; 
private javax.swing.JScrollPane jScrollPane1; 
private javax.swing.JTabbedPane jTabbedPane1; 
private javax.swing.JTabbedPane jTabbedPane2; 
// End of variables declaration     
} 

Answer 1

要添加一个组件，是自定义绘制有用的，我做的是这样的：

1. 创建exends的JPanel
2. 在类中重写paintComponent（）方法来绘制一个新的类矩形或任何你想要的其他形状。如果构造函数将首选大小设置为非零，则会很有帮助。
3. 编译新类。
4. 打开JPanel或JFrame的设计视图我想使用JPanel。
5. 将新类从“项目”选项卡拖放到您要使用的JFrame/Jpanel中。（如果要使用相同的自定义面板多次可能有助于在项目选项卡中选择类，并右键单击工具 - >添加到托盘，以便它在设计视图中位于托盘上。）

这里是一个示例类将以这种方式使用：

public class PanelWithRectangle extends JPanel { 

    public PanelWithRectangle() { 
     setPreferredSize(new Dimension(200,100)); 
    } 


    @Override 
    protected void paintComponent(Graphics g) { 
     super.paintComponent(g); 
     Graphics2D g2d = (Graphics2D) g; 
     g2d.draw(new Rectangle2D.Double(10, 10,20, 25)); 
    } 
} 

对于3D绘图它是一些有什么不同。 Swing不支持3D，所以我们需要使用一些JavaFX。对于JavaFX而不是扩展JPanel扩展JFXPanel，而不是重写paintComponent，请创建一个场景对象并使用setScene。此外，需要在JavaFX线程上调用JavaFX方法，因此我们需要使用Platform.runLater（）来在该线程上调用函数。

public class PanelWithBox extends JFXPanel { 

    public PanelWithBox() { 
     setPreferredSize(new Dimension(200,100)); 
     Platform.runLater(this::initFx); 
    } 

    private void initFx() { 
     Group g = new Group(); 
     Scene scene = new Scene(g); 
     Box box = new Box(20, 30, 40); 
     box.setMaterial(new PhongMaterial(Color.RED)); 
     box.getTransforms().addAll(Transform.translate(50, 25), new Rotate(30, new Point3D(1, 1, 1))); 
     g.getChildren().add(box); 
     setScene(scene); 
    } 
}