java - Java 透過性レンダリング エラー

Question

私は現在、天気、時刻、予報などを表示するキオスク スタイルの Java プログラムを開発しています。これは、プログラムがどのように見えるかのショットです(時刻が更新される前に撮影したスクリーンショット)。

さまざまなセクションが、paintComponent()メソッドがオーバーライドされた JPanel として作成されます。グラデーションのヘッダーと半透明の背景を描画します。ただし、これらのパネルのいずれかのコンテンツを変更すると、以前のコンテンツは削除されずに残されます。以下に例を示します。

ご覧のとおり、時刻が11:51から11:52に変わると数字が重なり、背景が薄くなりました（半透明の背景が上に描き直されたため）

グラフィックエラー

この重複を防ぐにはどうすればよいですか? 最終的に、個々のパネルがコンテンツを更新するときに画面全体を再描画する必要はありません。その特定のセクションだけを再描画したいと思います。背景を再描画してから、内部のすべてのコンポーネントを再描画するのは簡単です。

アップデート

いくつかの答えには、描画する領域をクリアすることが含まれます。背景画像を使用するg.clear()か消去するか。AlphaComposite.CLEARこれは、次の画像で確認できます。おそらく、領域をクリアする前に背景をコピーできれば、背景のその部分を再ペイントしてから、他の画像を適切に重ねることができます。考え？

更新 2

透明なパネルと背景の上に置かれたタイマーの完全な動作例を示す回答が提出されました。これは非常に便利ですが、サブコンポーネントを手動でペイントするつもりはありません。時刻、天気アイコン、気温はすべて、半透明のパネルに配置された JLabel です。個々のコンポーネントを手動でペイントする必要はありません。

Answer 1

同様の問題

ここで扱われます

また、「Swing プログラムは をオーバーライドするのではなく、オーバーライドする必要があります」ということにも注意してpaintComponent()くださいpaint()。Swing: ペイント メソッド。

Answer 2

私はこれを非常に迅速にまとめました。特別なことではありません...

プロジェクト全体は、JFrame、BackgroundImagePane、および ClockPane で構成されます

ClockPane は次のようになります (残りは再作成できます ;))

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.RoundRectangle2D;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.swing.Timer;

public class ClockPane extends javax.swing.JPanel {

    private Timer tick;

    protected static final SimpleDateFormat SDF = new SimpleDateFormat("HH:mm.ss");

    public ClockPane() {

        setOpaque(false);

        tick = new Timer(500, new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent ae) {

                repaint();

            }

        });

        tick.setCoalesce(true);
        tick.setRepeats(true);

        setPreferredSize(new Dimension(100, 100));
        setMinimumSize(new Dimension(100, 100));

    }

    @Override
    public void addNotify() {

        super.addNotify();

        tick.start();

    }

    @Override
    public void removeNotify() {

        tick.stop();

        super.removeNotify();

    }

    @Override
    protected void paintComponent(Graphics grphcs) {

        super.paintComponent(grphcs);

        Graphics2D g2d = (Graphics2D) grphcs;

        int width = getWidth() - 1;
        int height = getHeight() - 1;

        Color background = new Color(192, 192, 192, 128);
        Color border = new Color(128, 128, 128);
        RoundRectangle2D backing = new RoundRectangle2D.Float(0, 0, width, height, 20, 20);

        g2d.setPaint(background);
        g2d.fill(backing);
        g2d.setPaint(border);
        g2d.draw(backing);

        String text = SDF.format(new Date());
        FontMetrics fm = g2d.getFontMetrics();
        g2d.setPaint(Color.BLACK);

        int x = (width - fm.stringWidth(text)) / 2;
        int y = ((height - fm.getHeight()) / 2) + fm.getAscent();

        g2d.drawString(text, x, y);

    }

}

これにより、時計は0.5秒ごとに更新され、再描画に問題はありません

私が考えることができる唯一の重要なことはsetOpaque(false);

更新しました

この例は、ラベルとパネルだけで完全に実行されます (背景ペインはカスタム ペイント ジョブであり、日付ラベルの背景もペイントされていますが、そうではありません)。

今、私は一緒にハッキングしたので、あなたのものほど良くはありませんが、繰り返しますが、私は支払いを受けていません;)

import core.ui.UIUtilities;
import core.ui.WindowUtilities;
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.swing.Timer;
import javax.swing.UIManager;

public class MainFrame extends javax.swing.JFrame {

    /**
     * Creates new form MainFrame
     */
    public MainFrame() {

        setUndecorated(true);
        WindowUtilities.setOpaque(this, false);

        initComponents();

        Timer timer = new Timer(500, new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {

                lblTime.setText(new SimpleDateFormat("hh:MM:ss").format(new Date()));

            }
        });

        timer.setRepeats(true);
        timer.setCoalesce(true);
        timer.start();

        DateLabel label = new DateLabel();
        label.init();

        NewBackgroundPane backgroundPane = new NewBackgroundPane();
        backgroundPane.setLayout(new BorderLayout());
        backgroundPane.add(label, BorderLayout.NORTH);
        backgroundPane.add(pnlMain);

        add(backgroundPane, BorderLayout.CENTER);

        pack();

        setLocation(UIUtilities.centerOfDefaultScreen(this));

    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">
    private void initComponents() {
        java.awt.GridBagConstraints gridBagConstraints;

        pnlMain = new javax.swing.JPanel();
        jPanel2 = new javax.swing.JPanel();
        lblTime = new javax.swing.JLabel();
        lblExtTime = new javax.swing.JLabel();
        jPanel3 = new javax.swing.JPanel();
        jLabel3 = new javax.swing.JLabel();
        jLabel4 = new javax.swing.JLabel();
        jLabel5 = new javax.swing.JLabel();
        jLabel6 = new javax.swing.JLabel();
        jPanel4 = new javax.swing.JPanel();
        jPanel5 = new javax.swing.JPanel();
        jLabel11 = new javax.swing.JLabel();
        jLabel12 = new javax.swing.JLabel();
        jLabel13 = new javax.swing.JLabel();
        jLabel14 = new javax.swing.JLabel();
        jPanel6 = new javax.swing.JPanel();
        jLabel15 = new javax.swing.JLabel();
        jLabel16 = new javax.swing.JLabel();
        jLabel17 = new javax.swing.JLabel();
        jLabel18 = new javax.swing.JLabel();
        jPanel7 = new javax.swing.JPanel();
        jLabel19 = new javax.swing.JLabel();
        jLabel20 = new javax.swing.JLabel();
        jLabel21 = new javax.swing.JLabel();
        jLabel22 = new javax.swing.JLabel();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        pnlMain.setOpaque(false);
        pnlMain.setLayout(new java.awt.GridBagLayout());

        jPanel2.setOpaque(false);
        jPanel2.setLayout(new java.awt.GridBagLayout());

        lblTime.setFont(lblTime.getFont().deriveFont(lblTime.getFont().getStyle() | java.awt.Font.BOLD, lblTime.getFont().getSize()+18));
        lblTime.setForeground(new java.awt.Color(255, 255, 255));
        lblTime.setText("jLabel1");
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 1;
        jPanel2.add(lblTime, gridBagConstraints);

        lblExtTime.setFont(lblExtTime.getFont().deriveFont(lblExtTime.getFont().getSize()+6f));
        lblExtTime.setForeground(new java.awt.Color(255, 255, 255));
        lblExtTime.setText("AM EDT");
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 1;
        gridBagConstraints.gridy = 1;
        gridBagConstraints.anchor = java.awt.GridBagConstraints.PAGE_START;
        jPanel2.add(lblExtTime, gridBagConstraints);

        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 1;
        gridBagConstraints.fill = java.awt.GridBagConstraints.HORIZONTAL;
        gridBagConstraints.weightx = 1.0;
        gridBagConstraints.insets = new java.awt.Insets(2, 2, 2, 2);
        pnlMain.add(jPanel2, gridBagConstraints);

        jPanel3.setOpaque(false);
        jPanel3.setLayout(new java.awt.GridBagLayout());

        jLabel3.setIcon(new javax.swing.ImageIcon(getClass().getResource("/transparentUpdate/Overcast.png"))); // NOI18N
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 0;
        gridBagConstraints.gridheight = 2;
        jPanel3.add(jLabel3, gridBagConstraints);

        jLabel4.setFont(jLabel4.getFont().deriveFont(jLabel4.getFont().getSize()+6f));
        jLabel4.setForeground(new java.awt.Color(255, 255, 255));
        jLabel4.setText("<html>Currenctly<br>Overast</html>");
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 1;
        gridBagConstraints.gridy = 0;
        gridBagConstraints.gridwidth = 2;
        gridBagConstraints.anchor = java.awt.GridBagConstraints.FIRST_LINE_START;
        jPanel3.add(jLabel4, gridBagConstraints);

        jLabel5.setFont(jLabel5.getFont().deriveFont(jLabel5.getFont().getSize()+12f));
        jLabel5.setForeground(new java.awt.Color(255, 255, 255));
        jLabel5.setText("69");
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 1;
        gridBagConstraints.gridy = 1;
        gridBagConstraints.anchor = java.awt.GridBagConstraints.LAST_LINE_START;
        jPanel3.add(jLabel5, gridBagConstraints);

        jLabel6.setForeground(new java.awt.Color(255, 255, 255));
        jLabel6.setText("/65");
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 2;
        gridBagConstraints.gridy = 1;
        gridBagConstraints.anchor = java.awt.GridBagConstraints.LAST_LINE_START;
        jPanel3.add(jLabel6, gridBagConstraints);

        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 2;
        gridBagConstraints.fill = java.awt.GridBagConstraints.HORIZONTAL;
        gridBagConstraints.weightx = 1.0;
        gridBagConstraints.insets = new java.awt.Insets(2, 2, 2, 2);
        pnlMain.add(jPanel3, gridBagConstraints);

        jPanel4.setOpaque(false);
        jPanel4.setLayout(new java.awt.GridBagLayout());

        jPanel5.setOpaque(false);
        jPanel5.setLayout(new java.awt.GridBagLayout());

        jLabel11.setFont(jLabel11.getFont().deriveFont(jLabel11.getFont().getSize()+4f));
        jLabel11.setForeground(new java.awt.Color(255, 255, 255));
        jLabel11.setText("Today");
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 0;
        gridBagConstraints.gridwidth = 2;
        jPanel5.add(jLabel11, gridBagConstraints);

        jLabel12.setForeground(new java.awt.Color(255, 255, 255));
        jLabel12.setIcon(new javax.swing.ImageIcon(getClass().getResource("/transparentUpdate/SmallOvercast.png"))); // NOI18N
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 1;
        gridBagConstraints.gridheight = 2;
        jPanel5.add(jLabel12, gridBagConstraints);

        jLabel13.setFont(jLabel13.getFont().deriveFont(jLabel13.getFont().getSize()+4f));
        jLabel13.setForeground(new java.awt.Color(255, 255, 255));
        jLabel13.setText("83");
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 1;
        gridBagConstraints.gridy = 1;
        gridBagConstraints.anchor = java.awt.GridBagConstraints.PAGE_START;
        jPanel5.add(jLabel13, gridBagConstraints);

        jLabel14.setForeground(new java.awt.Color(255, 255, 255));
        jLabel14.setText("65");
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 1;
        gridBagConstraints.gridy = 2;
        gridBagConstraints.anchor = java.awt.GridBagConstraints.PAGE_START;
        jPanel5.add(jLabel14, gridBagConstraints);

        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 0;
        gridBagConstraints.anchor = java.awt.GridBagConstraints.PAGE_START;
        gridBagConstraints.insets = new java.awt.Insets(2, 4, 2, 4);
        jPanel4.add(jPanel5, gridBagConstraints);

        jPanel6.setOpaque(false);
        jPanel6.setLayout(new java.awt.GridBagLayout());

        jLabel15.setFont(jLabel15.getFont().deriveFont(jLabel15.getFont().getSize()+4f));
        jLabel15.setForeground(new java.awt.Color(255, 255, 255));
        jLabel15.setText("Sunday");
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 0;
        gridBagConstraints.gridwidth = 2;
        jPanel6.add(jLabel15, gridBagConstraints);

        jLabel16.setForeground(new java.awt.Color(255, 255, 255));
        jLabel16.setIcon(new javax.swing.ImageIcon(getClass().getResource("/transparentUpdate/Sunny.png"))); // NOI18N
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 1;
        gridBagConstraints.gridheight = 2;
        jPanel6.add(jLabel16, gridBagConstraints);

        jLabel17.setFont(jLabel17.getFont().deriveFont(jLabel17.getFont().getSize()+4f));
        jLabel17.setForeground(new java.awt.Color(255, 255, 255));
        jLabel17.setText("82");
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 1;
        gridBagConstraints.gridy = 1;
        gridBagConstraints.anchor = java.awt.GridBagConstraints.PAGE_START;
        jPanel6.add(jLabel17, gridBagConstraints);

        jLabel18.setForeground(new java.awt.Color(255, 255, 255));
        jLabel18.setText("64");
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 1;
        gridBagConstraints.gridy = 2;
        gridBagConstraints.anchor = java.awt.GridBagConstraints.PAGE_START;
        jPanel6.add(jLabel18, gridBagConstraints);

        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 1;
        gridBagConstraints.gridy = 0;
        gridBagConstraints.anchor = java.awt.GridBagConstraints.PAGE_START;
        gridBagConstraints.insets = new java.awt.Insets(2, 4, 2, 4);
        jPanel4.add(jPanel6, gridBagConstraints);

        jPanel7.setOpaque(false);
        jPanel7.setLayout(new java.awt.GridBagLayout());

        jLabel19.setFont(jLabel19.getFont().deriveFont(jLabel19.getFont().getSize()+4f));
        jLabel19.setForeground(new java.awt.Color(255, 255, 255));
        jLabel19.setText("Monday");
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 0;
        gridBagConstraints.gridwidth = 2;
        jPanel7.add(jLabel19, gridBagConstraints);

        jLabel20.setForeground(new java.awt.Color(255, 255, 255));
        jLabel20.setIcon(new javax.swing.ImageIcon(getClass().getResource("/transparentUpdate/Cloudy.png"))); // NOI18N
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 1;
        gridBagConstraints.gridheight = 2;
        jPanel7.add(jLabel20, gridBagConstraints);

        jLabel21.setFont(jLabel21.getFont().deriveFont(jLabel21.getFont().getSize()+4f));
        jLabel21.setForeground(new java.awt.Color(255, 255, 255));
        jLabel21.setText("83");
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 1;
        gridBagConstraints.gridy = 1;
        gridBagConstraints.anchor = java.awt.GridBagConstraints.PAGE_START;
        jPanel7.add(jLabel21, gridBagConstraints);

        jLabel22.setForeground(new java.awt.Color(255, 255, 255));
        jLabel22.setText("84");
        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 1;
        gridBagConstraints.gridy = 2;
        gridBagConstraints.anchor = java.awt.GridBagConstraints.PAGE_START;
        jPanel7.add(jLabel22, gridBagConstraints);

        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 2;
        gridBagConstraints.gridy = 0;
        gridBagConstraints.anchor = java.awt.GridBagConstraints.PAGE_START;
        gridBagConstraints.insets = new java.awt.Insets(2, 4, 2, 4);
        jPanel4.add(jPanel7, gridBagConstraints);

        gridBagConstraints = new java.awt.GridBagConstraints();
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 3;
        gridBagConstraints.fill = java.awt.GridBagConstraints.HORIZONTAL;
        gridBagConstraints.weightx = 1.0;
        gridBagConstraints.insets = new java.awt.Insets(2, 2, 2, 2);
        pnlMain.add(jPanel4, gridBagConstraints);

        getContentPane().add(pnlMain, java.awt.BorderLayout.CENTER);

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

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /*
         * Set the Nimbus look and feel
         */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /*
         * If Nimbus (introduced in Java SE 6) is not available, stay with the
         * default look and feel. For details see
         * http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
         */
        try {

            UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());

        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(MainFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(MainFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(MainFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(MainFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /*
         * Create and display the form
         */
        java.awt.EventQueue.invokeLater(new Runnable() {

            public void run() {
                new MainFrame().setVisible(true);
            }
        });
    }
    // Variables declaration - do not modify
    private javax.swing.JLabel jLabel11;
    private javax.swing.JLabel jLabel12;
    private javax.swing.JLabel jLabel13;
    private javax.swing.JLabel jLabel14;
    private javax.swing.JLabel jLabel15;
    private javax.swing.JLabel jLabel16;
    private javax.swing.JLabel jLabel17;
    private javax.swing.JLabel jLabel18;
    private javax.swing.JLabel jLabel19;
    private javax.swing.JLabel jLabel20;
    private javax.swing.JLabel jLabel21;
    private javax.swing.JLabel jLabel22;
    private javax.swing.JLabel jLabel3;
    private javax.swing.JLabel jLabel4;
    private javax.swing.JLabel jLabel5;
    private javax.swing.JLabel jLabel6;
    private javax.swing.JPanel jPanel2;
    private javax.swing.JPanel jPanel3;
    private javax.swing.JPanel jPanel4;
    private javax.swing.JPanel jPanel5;
    private javax.swing.JPanel jPanel6;
    private javax.swing.JPanel jPanel7;
    private javax.swing.JLabel lblExtTime;
    private javax.swing.JLabel lblTime;
    private javax.swing.JPanel pnlMain;
    // End of variables declaration
}

生活を楽にするために、背景ペイン

import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;

public class NewBackgroundPane extends javax.swing.JPanel {

    /**
     * Creates new form NewBackgroundPane
     */
    public NewBackgroundPane() {
        initComponents();
    }

    @Override
    protected void paintComponent(Graphics g) {

        super.paintComponent(g);

        Graphics2D g2d = (Graphics2D) g.create();

        int width = getWidth() - 1;
        int height = getHeight() - 1;

        g2d.setColor(Color.LIGHT_GRAY);
        g2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.5f));
        g2d.fillRoundRect(0, 0, width, height, 20, 20);
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">
    private void initComponents() {

        setOpaque(false);

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
        this.setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 400, Short.MAX_VALUE)
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 300, Short.MAX_VALUE)
        );
    }// </editor-fold>
    // Variables declaration - do not modify
    // End of variables declaration
}

それでも動作しない場合、私が考えることができる唯一の他の問題は、フルスクリーンの排他モードに関係している可能性があります。私はそれをテストしていません:P

Answer 3

ペイントを行う前に、g.clearRect(0,0,w,h)呼び出しを行います。これにより、指定された領域内のすべてが削除され、前のフレームの上に描画されることはありません。

クリアのために画面がわずかに点滅するため、いくつかのダブル バッファリング テクニックを適用することをお勧めします。