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  2. The JScrollPane content doesn't refesh while scrolling

The JScrollPane content doesn't refesh while scrolling

由 走远了吗. 提交于 2019-12-11 10:33:37

问题


I'm creating a simple gui of options that containing a JScrollPanel.

The problem is when I'm scrolling all the content of the JPanel inside my JScrollPanel doesn't refresh like that : Bad Refresh Scrolling

Another issues is that not all my text fields are well painted and the combobox fields are behind the first text field.

Here my code :

  • OptionsPanel.java the source of the problem

    package scroll;

import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.TextEvent;
import java.awt.event.TextListener;

import javax.swing.JPanel;
import javax.swing.JScrollPane;

import scroll.NavigationButtons.Navigation;

public class OptionsPanel extends JPanel implements ActionListener, TextListener {

    private static final long serialVersionUID = 3800714599366218432L;

    private NavigationButtons navBtn;

    private ChangeOptionCB language;

    private ChangeOptionTF option1;

    private ChangeOptionTF option2;

    private ChangeOptionTF option3;

    private ChangeOptionTF option4;

    private ChangeOptionTF option5;

    private ChangeOptionTF option6;

    private ChangeOptionTF option7;

    private JScrollPane scrollPane;

    public OptionsPanel() {
        super();

        GridBagLayout layout = new GridBagLayout();
        setLayout(layout);

        GridBagConstraints constraint = new GridBagConstraints();

        JPanel optionsPanel = new JPanel();
        GridBagLayout l = new GridBagLayout();
        GridBagConstraints c = new GridBagConstraints();

        optionsPanel.setLayout(l);



        String[] langues = {"en", "fr", "es"};
        language = new ChangeOptionCB("Languages", langues);
        language.addTextListener(this);
        c.gridx = 0;
        c.gridy = 0;
        c.fill = GridBagConstraints.HORIZONTAL;
        c.anchor = GridBagConstraints.PAGE_START;
        c.weightx = 1;
        c.weighty = 0.1;
        optionsPanel.add(language, c);

        option1 = new ChangeOptionTF("option 1");
        option1.addTextListener(this);
        option1.setText("option 1");
        c.gridx = 0;
        c.gridy = 1;
        c.fill = GridBagConstraints.HORIZONTAL;
        c.anchor = GridBagConstraints.PAGE_START;
        c.weightx = 1;
        c.weighty = 0.1;
        optionsPanel.add(option1, c);

        option2 = new ChangeOptionTF("option 2");
        option2.addTextListener(this);
        option2.setText("option 2");
        c.gridx = 0;
        c.gridy = 2;
        c.fill = GridBagConstraints.HORIZONTAL;
        c.anchor = GridBagConstraints.PAGE_START;
        c.weightx = 1;
        c.weighty = 0.1;
        optionsPanel.add(option2, c);

        option3 = new ChangeOptionTF("option 3");
        option3.addTextListener(this);
        option3.setText("option 3");
        c.gridx = 0;
        c.gridy = 3;
        c.fill = GridBagConstraints.HORIZONTAL;
        c.anchor = GridBagConstraints.PAGE_START;
        c.weightx = 1;
        c.weighty = 0.1;
        optionsPanel.add(option3, c);

        option4 = new ChangeOptionTF("option 4");
        option4.addTextListener(this);
        option4.setText("option 4");
        c.gridx = 0;
        c.gridy = 4;
        c.fill = GridBagConstraints.HORIZONTAL;
        c.anchor = GridBagConstraints.PAGE_START;
        c.weightx = 1;
        c.weighty = 0.1;
        optionsPanel.add(option4, c);

        option5 = new ChangeOptionTF("option 5");
        option5.addTextListener(this);
        option5.setText("option 5");
        c.gridx = 0;
        c.gridy = 5;
        c.fill = GridBagConstraints.HORIZONTAL;
        c.anchor = GridBagConstraints.PAGE_START;
        c.weightx = 1;
        c.weighty = 0.1;
        optionsPanel.add(option5, c);

        option6 = new ChangeOptionTF("option 6");
        option6.addTextListener(this);
        option6.setText("option 6");
        c.gridx = 0;
        c.gridy = 6;
        c.fill = GridBagConstraints.HORIZONTAL;
        c.anchor = GridBagConstraints.PAGE_START;
        c.weightx = 1;
        c.weighty = 0.1;
        optionsPanel.add(option6, c);

        option7 = new ChangeOptionTF("option 7");
        option7.addTextListener(this);
        option7.setText("option 7");
        c.gridx = 0;
        c.gridy = 7;
        c.fill = GridBagConstraints.HORIZONTAL;
        c.anchor = GridBagConstraints.PAGE_START;
        c.weightx = 1;
        c.weighty = 0.1;
        optionsPanel.add(option7, c);

        scrollPane = new JScrollPane(optionsPanel);

        constraint.gridx = 0;
        constraint.gridy = 0;
        constraint.fill = GridBagConstraints.BOTH;
        constraint.weightx = 1;
        constraint.weighty = 1;
        add(scrollPane, constraint);

        navBtn = new NavigationButtons(NavigationButtons.EXIT);
        navBtn.addActionListener(this);
        constraint.gridx = 0;
        constraint.gridy = 1;
        constraint.fill = GridBagConstraints.HORIZONTAL;
        constraint.weightx = 1;
        constraint.weighty = 0.25;
        add(navBtn, constraint);

    }

    @Override
    public void actionPerformed(ActionEvent ae) {
        if (navBtn == ae.getSource()) {
            int id = ae.getID();
            if (Navigation.EXIT.getId() == id) {
                System.out.println("Get out !!");
            } 
        }
    }

    @Override
    public void textValueChanged(TextEvent te) {
        if (language == te.getSource()) {
            System.out.println("The option as changed : "+language.getOption());
        }
        if (option1 == te.getSource()) {
            System.out.println("The option as changed : "+option1.getNewText());
        }
        if (option2 == te.getSource()) {
            System.out.println("The option as changed : "+option2.getNewText());
        }
        if (option3 == te.getSource()) {
            System.out.println("The option as changed : "+option3.getNewText());
        }
        if (option4 == te.getSource()) {
            System.out.println("The option as changed : "+option4.getNewText());
        }
        if (option5 == te.getSource()) {
            System.out.println("The option as changed : "+option5.getNewText());
        }
        if (option6 == te.getSource()) {
            System.out.println("The option as changed : "+option6.getNewText());
        }
        if (option7 == te.getSource()) {
            System.out.println("The option as changed : "+option7.getNewText());
        }
        scrollPane.revalidate();
        scrollPane.repaint();
    }

}

  • The Main Class

    package scroll;

import java.awt.Dimension;
import javax.swing.JFrame;

public class ScrollTest {

    public static void main(String[] args) {

        JFrame frame = new JFrame();

        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setResizable(false);
        frame.setContentPane(new OptionsPanel());
        frame.setTitle("Scrool Test");
        frame.pack();

        Dimension dimension = new Dimension(691, 263);
        frame.setSize(dimension);
        frame.setPreferredSize(dimension);
        frame.setLocationRelativeTo(null);

        frame.pack();
        frame.setVisible(true);
    }
}

  • The different stuff that you need :

    package scroll;

import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.TextEvent;
import java.awt.event.TextListener;

import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingConstants;
import javax.swing.event.EventListenerList;

public class ChangeOptionCB extends JPanel implements ActionListener {

    private static final long serialVersionUID = 3355314012553851743L;
    private JComboBox cb;
    private JButton saveBtn;

    private EventListenerList listeners;

    public ChangeOptionCB(String label, String[] list) {

        listeners = new EventListenerList();

        GridBagLayout layout = new GridBagLayout();
        GridBagConstraints c = new GridBagConstraints();
        setLayout(layout);

        JLabel jLabel = new JLabel(label);
        jLabel.setHorizontalAlignment(SwingConstants.LEFT);
        c.fill = GridBagConstraints.LINE_START;
        c.gridx = 0;
        c.gridy = 0;
        c.weightx = 0.1;
        add(jLabel, c);

        cb = new JComboBox(list);
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 1;
        c.gridy = 0;
        c.weightx = 0.8;
        add(cb, c);


        saveBtn = new JButton("Save");
        saveBtn.addActionListener(this);

        c.gridx = 2;
        c.gridy = 0;
        c.weightx = 0;
        c.anchor = GridBagConstraints.LINE_END;
        add(saveBtn, c);

    }

    @Override
    public void actionPerformed(ActionEvent ae) {
        if (ae.getSource() == saveBtn) {
            fireTextAsChange();
        }
    }

    public String getOption() {
        return (String) cb.getSelectedItem();
    }

    public void addTextListener(TextListener listener) {
        listeners.add(TextListener.class, listener);
    }

    public void removeActionListener(TextListener listener) {
        listeners.remove(TextListener.class, listener);
    }

    private void fireTextAsChange(){
        TextListener[] listenerList = (TextListener[])listeners.getListeners(TextListener.class);

        for(TextListener listener : listenerList){
            listener.textValueChanged(new TextEvent(this, 0));
        }
    }

}

package scroll;

import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.TextField;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.TextEvent;
import java.awt.event.TextListener;

import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.event.EventListenerList;

public class ChangeOptionTF extends JPanel implements ActionListener {

    private static final long serialVersionUID = 3355314012553851743L;
    private TextField tf;
    private JButton saveBtn;

    private EventListenerList listeners;

    public ChangeOptionTF(String label) {

        listeners = new EventListenerList();

        GridBagLayout layout = new GridBagLayout();
        GridBagConstraints c = new GridBagConstraints();
        setLayout(layout);

        JLabel jLabel = new JLabel(label);
        c.fill = GridBagConstraints.BOTH;
        c.gridx = 0;
        c.gridy = 0;
        c.weightx = 1;
        add(jLabel, c);

        tf = new TextField();
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 0;
        c.gridy = 1;
        c.weightx = 0.5;
        add(tf, c);


        saveBtn = new JButton("Save");
        saveBtn.addActionListener(this);

        c.gridx = 2;
        c.gridy = 1;
        c.weightx = 0;
        c.anchor = GridBagConstraints.LINE_END;
        add(saveBtn, c);

    }

    @Override
    public void actionPerformed(ActionEvent ae) {
        if (ae.getSource() == saveBtn) {
            fireTextAsChange();
        }
    }

    public String getNewText() {
        return tf.getText();
    }

    public void addTextListener(TextListener listener) {
        listeners.add(TextListener.class, listener);
    }

    public void removeActionListener(TextListener listener) {
        listeners.remove(TextListener.class, listener);
    }

    private void fireTextAsChange(){
        TextListener[] listenerList = (TextListener[])listeners.getListeners(TextListener.class);

        for(TextListener listener : listenerList){
            listener.textValueChanged(new TextEvent(this, 0));
        }
    }

    public void setText(String text) {
        tf.setText(text);
    }

}

package scroll;

import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.event.EventListenerList;

public class NavigationButtons extends JPanel implements ActionListener {

    private static final long serialVersionUID = -4844499317626526067L;

    public enum Navigation {
        NEXT(1), CANCEL(0), EXIT(-1);

        private int id;

        private Navigation(int id) {
            this.id = id;
        }

        public int getId() {
            return id;
        }
    }

    public static int NEXT_CANCEL = 0;
    public static int CANCEL = 1;
    public static int EXIT = 2;

    private JButton cancel;
    private JButton next;
    private JButton exit;

    private EventListenerList listeners;

    public NavigationButtons(int type) {

        listeners = new EventListenerList();

        GridBagLayout layout = new GridBagLayout();
        GridBagConstraints c = new GridBagConstraints();
        setLayout(layout);

        if ((NEXT_CANCEL == type) || (CANCEL == type)) {
            cancel = new JButton("Cancel");
            cancel.addActionListener(this);

            c.gridwidth = 1;
            c.anchor = GridBagConstraints.LINE_START;
            c.weightx = 1;
            add(cancel, c);
        }

        if (NEXT_CANCEL == type) {
            next = new JButton("Next");
            next.addActionListener(this);

            c.gridwidth = 1;
            c.anchor = GridBagConstraints.LINE_END;
            c.weightx = 0;
            add(next, c);
        }

        if (EXIT == type) {
            exit = new JButton("Exit");
            exit.addActionListener(this);

            c.gridwidth = 1;
            c.anchor = GridBagConstraints.LINE_END;
            c.weightx = 1;
            add(exit, c);
        }

    }

    public void setNextEnable(boolean b) {
        next.setEnabled(b);
    }

    @Override
    public void actionPerformed(ActionEvent ae) {
        if (ae.getSource() == next) {
            fireActionPerformed(Navigation.NEXT);
        }
        if (ae.getSource() == cancel) {
            fireActionPerformed(Navigation.CANCEL);
        }
        if (ae.getSource() == exit) {
            fireActionPerformed(Navigation.EXIT);
        }
    }

    public void addActionListener(ActionListener listener) {
        listeners.add(ActionListener.class, listener);
    }

    public void removeActionListener(ActionListener listener) {
        listeners.remove(ActionListener.class, listener);
    }

    public void fireActionPerformed(Navigation nav){
        ActionListener[] listenerList = (ActionListener[])listeners.getListeners(ActionListener.class);

        for(ActionListener listener : listenerList){
            listener.actionPerformed(new ActionEvent(this, nav.getId(), null));
        }
    }
}

What is wrong in my code that make this ugly refresh ? I don't understand.

Maybe I need to implement a kind of listener that repaint my frame each time I scroll ?

The more strange things is, if I replace 

add(scrollPane, constraint);

by

add(optionsPane, constraint);

the content get out well (at least in this example).

Thank's you

Julien


回答1:


The basic problem is, you're using java.awt.TextField which is a heavy weight component inside a lighweight container. This is just asking for issues, they tend not to play well together.

Instead, use a javax.swing.JTextField

import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.TextEvent;
import java.awt.event.TextListener;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.event.EventListenerList;

public class ChangeOptionTF extends JPanel implements ActionListener {

    private static final long serialVersionUID = 3355314012553851743L;
    private JTextField tf;
    private JButton saveBtn;

    private EventListenerList listeners;

    public ChangeOptionTF(String label) {

        listeners = new EventListenerList();

        GridBagLayout layout = new GridBagLayout();
        GridBagConstraints c = new GridBagConstraints();
        setLayout(layout);

        JLabel jLabel = new JLabel(label);
        c.fill = GridBagConstraints.BOTH;
        c.gridx = 0;
        c.gridy = 0;
        c.weightx = 1;
        add(jLabel, c);

        tf = new JTextField();


来源：https://stackoverflow.com/questions/33899843/the-jscrollpane-content-doesnt-refesh-while-scrolling

标签
java
swing
jscrollpane
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