Java - 如何在JFrame中的IDE生成的JPanel上繪制形狀

Question

我正在使用NetBeans IDE來編寫GUI應用程序。 它將計算各種原始2D / 3D形狀的面積/體積。 我在其中創建了一個新的JFrame - 一個JTabbedPane ，它有兩個用於2D和3D形狀的選項卡。

我計划為每個形狀的標簽創建自定義jpegs，這不是問題，但我無法在形狀類型標簽內繪制形狀（見圖片）。

只有一個.java文件，我在這里粘貼了它的內容。 請幫助我，我非常困惑，我怎么能解決這個問題。

// @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

要添加對自定義繪圖有用的組件，我所做的是：

1. 創建一個釋放JPanel的新類
2. 在類中重寫paintComponent（）方法以繪制矩形或您想要的任何其他形狀。 如果構造函數將首選大小設置為非零，則會很有幫助。
3. 編譯新類。
4. 打開我想要使用JPanel的JPanel或JFrame的Design視圖。
5. 將新類從Projects選項卡拖到要使用它的JFrame / Jpanel上。（如果要多次使用相同的自定義Panel，在項目選項卡中選擇類並右鍵單擊可能會有幫助。工具 - >添加到托盤，使其位於設計視圖中的托盤上。）

這是一個以這種方式使用的示例類：

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));
    }
}

對於3D繪圖，它有些不同。 Swing不支持3D，所以我們需要使用一些JavaFX。 對於JavaFX而不是擴展JPanel擴展JFXPanel而不是覆蓋paintComponent，創建一個場景對象並使用setScene。 此外，需要在JavaFX線程上調用JavaFX方法，因此我們需要使用Platform.runLater（）來在該線程上調用函數。

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);
    }
}