Question

i am working on an animation that when i pressed a button the each row of the corresponding table is highlighted one by one from top to bottom. However, when the animation started, the table cannot repaint correctly, the ui of the table is corrupted somehow. here is my code below.

/*

* To change this template, choose Tools | Templates
* and open the template in the editor.
*/

/*
* TableFrame.java
*
* Created on 2010/8/5, 下午 04:07:10
*/

package test;
import javax.swing.;
import javax.swing.table.;
/**
*
* @author Administrator
*/
public class TableFrame extends javax.swing.JFrame {
StringThread1 t = null;

public JTable table;
public JScrollPane getScrollPane(){
return this.jScrollPane1;
}
/** Creates new form TableFrame */
public TableFrame() {
initComponents();
table = new JTable(new javax.swing.table.DefaultTableModel(100, 2));
this.jScrollPane1.setViewportView(table);
for(int i = 0; i < 100; i++){
for(int j = 0; j < 2; j++){
table.setValueAt(new Integer(i), i, j);
}
}
t = new StringThread1(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() {

    jScrollPane1 = new javax.swing.JScrollPane();
    jButton1 = new javax.swing.JButton();

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

    jScrollPane1.setBorder(javax.swing.BorderFactory.createLineBorder(new java.awt.Color(0, 0, 0)));

    jButton1.setText("jButton1");
    jButton1.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton1ActionPerformed(evt);
        }
    });

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
    getContentPane().setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addGroup(layout.createSequentialGroup()
                    .addContainerGap()
                    .addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 380, Short.MAX_VALUE))
                .addGroup(layout.createSequentialGroup()
                    .addGap(32, 32, 32)
                    .addComponent(jButton1)))
            .addContainerGap())
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap()
            .addComponent(jButton1)
            .addGap(18, 18, 18)
            .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 201, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addContainerGap(48, Short.MAX_VALUE))
    );

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

boolean play = false;
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    this.t.start();
        play = !play;
}                                        

class StringThread1 extends Thread
{
    private TableFrame str;

    StringThread1 (TableFrame s)
    {
        str=s;
    }

    public void run() {
        int y = 0;
        while(true){
            try{
                System.out.println("y " + String.valueOf(y));
                this.sleep(500);
                this.str.table.setRowSelectionInterval(y, y);
                int rp = y * this.str.table.getRowHeight();
                int halfHeight = this.str.getScrollPane().getHeight() / 2 - this.str.table.getRowHeight();
                if(rp + this.str.table.getRowHeight() * 2 >= this.str.getScrollPane().getVerticalScrollBar().getValue() + this.str.getScrollPane().getHeight()){
                    this.str.getScrollPane().getVerticalScrollBar().setValue((y) * this.str.table.getRowHeight());
                }

                else{
                    this.str.getScrollPane().getVerticalScrollBar().setValue(0);
                }


                if(y == 99){
                    y = 0;
                }y+= 1;
            } catch(InterruptedException e){}
        }
    }
}

/**
* @param args the command line arguments
*/
public static void main(String args[]) {
    java.awt.EventQueue.invokeLater(new Runnable() {
        public void run() {
            new TableFrame().setVisible(true);
        }
    });
}

// Variables declaration - do not modify                     
private javax.swing.JButton jButton1;
private javax.swing.JScrollPane jScrollPane1;
// End of variables declaration                   

}

Answer 1

There’s a golden rule – don’t manipulate displayed GUI items in threads outside the Event Displatch Thread. So, you need to use SwingUtilities.invokeLater() to do these calls:

this.str.table.setRowSelectionInterval(y, y);

and

this.str.getScrollPane().getVerticalScrollBar().setValue((y) * this.str.table.getRowHeight());

and

this.str.getScrollPane().getVerticalScrollBar().setValue(0);

You can wrap each one, or wrap them all in a single call.