Java Source - JLabel Demo

Shows how to specify horizontal and vertical alignment as well as how to align a label's text and image.
Trình bày cách làm thế nào để xác định sự liên kết ngang, dọc và cũng như làm thế nào để sắp xếp văn bản và image trên label.




LabelDemo.java

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package components;

import java.awt.GridLayout;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JFrame;
import javax.swing.ImageIcon;
import javax.swing.UIManager;
import javax.swing.SwingUtilities;

/*
 * LabelDemo.java needs one other file:
 *   images/middle.gif
 */
public class LabelDemo extends JPanel {
    public LabelDemo() {
        super(new GridLayout(3,1));  //3 rows, 1 column
        JLabel label1, label2, label3;

        ImageIcon icon = createImageIcon("images/vnlives.png",
                                         "a pretty but meaningless splat");

        //Create the first label.
        label1 = new JLabel("Image and Text",
                            icon,
                            JLabel.CENTER);
        //Set the position of its text, relative to its icon:
        label1.setVerticalTextPosition(JLabel.BOTTOM);
        label1.setHorizontalTextPosition(JLabel.CENTER);

        //Create the other labels.
        label2 = new JLabel("Text-Only Label");
        label3 = new JLabel(icon);

        //Create tool tips, for the heck of it.
        label1.setToolTipText("A label containing both image and text");
        label2.setToolTipText("A label containing only text");
        label3.setToolTipText("A label containing only an image");

        //Add the labels.
        add(label1);
        add(label2);
        add(label3);
    }

    /** Returns an ImageIcon, or null if the path was invalid. */
    protected static ImageIcon createImageIcon(String path,
                                               String description) {
        java.net.URL imgURL = LabelDemo.class.getResource(path);
        if (imgURL != null) {
            return new ImageIcon(imgURL, description);
        } else {
            System.err.println("Couldn't find file: " + path);
            return null;
        }
    }

    /**
     * Create the GUI and show it.  For thread safety,
     * this method should be invoked from the
     * event dispatch thread.
     */
    private static void createAndShowGUI() {
        //Create and set up the window.
        JFrame frame = new JFrame("LabelDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Add content to the window.
        frame.add(new LabelDemo());

        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        //Schedule a job for the event dispatch thread:
        //creating and showing this application's GUI.
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
        //Turn off metal's use of bold fonts
            UIManager.put("swing.boldMetal", Boolean.FALSE);
               
        createAndShowGUI();
            }
        });
    }
}

Kết quả - Result