按下 JButton 时尝试更改图像

Question

我试图在按下任何 JButton 时更改面板上的图像。我已经设置了一个图像数组，并且需要它在按下后更改为数组中的下一个图像。这是我的代码：

public class SimpleGui implements ActionListener {
    JButton button = new JButton("Very Happy");
    JButton buttonTwo = new JButton("Happy");
    JButton buttonThree = new JButton("Neutral");
    JButton buttonFour = new JButton("Sad");
    JButton buttonFive = new JButton("Very Sad");
    static int[] ButtonArray = new int[5];
    private static String[] imageList = { "res/snow.jpg", "res/test-gm.jpg" };

    public int i = 0;

    public static void main(String[] args) throws FileNotFoundException {

        SimpleGui gui = new SimpleGui();
        gui.go();

        File file = new File("out.txt");
        FileOutputStream fos = new FileOutputStream(file);
        PrintStream ps = new PrintStream(fos);
        System.setOut(ps);

        ButtonArray[0] = 0;
        ButtonArray[1] = 0;
        ButtonArray[2] = 0;
        ButtonArray[3] = 0;
        ButtonArray[4] = 0;

    }

    public void go() {
        JFrame frame = new JFrame();
        JPanel panel = new JPanel();
        panel.setBackground(Color.darkGray);

        panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));

        button.addActionListener(this);
        buttonTwo.addActionListener(this);
        buttonThree.addActionListener(this);
        buttonFour.addActionListener(this);
        buttonFive.addActionListener(this);
        panel.add(button);
        panel.add(buttonTwo);
        panel.add(buttonThree);
        panel.add(buttonFour);
        panel.add(buttonFive);

        frame.getContentPane().add(BorderLayout.EAST, panel);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(650, 600);
        frame.setVisible(true);

        ImageIcon image = new ImageIcon(imageList[i]);
        ImageIcon image1 = new ImageIcon(imageList[i + 1]);
        JLabel label = new JLabel("", image, JLabel.CENTER);
        JPanel panel2 = new JPanel(new BorderLayout());
        panel2.add(label, BorderLayout.CENTER);
        panel2.setLayout(new BoxLayout(panel2, BoxLayout.Y_AXIS));
        frame.add(panel2, BorderLayout.CENTER);

        frame.setVisible(true);
    }

    public void actionPerformed(ActionEvent event) {

        if (event.getSource() == button) {
            ButtonArray[0] = 1;
            ButtonArray[1] = 0;
            ButtonArray[2] = 0;
            ButtonArray[3] = 0;
            ButtonArray[4] = 0;
            System.out.println("Very Happy");

        }
        // buttonTwo = (JButton) event.getSource();
        if (event.getSource() == buttonTwo) {
            ButtonArray[0] = 0;
            ButtonArray[1] = 1;
            ButtonArray[2] = 0;
            ButtonArray[3] = 0;
            ButtonArray[4] = 0;
            System.out.println("Happy");

        }
        // buttonThree = (JButton) event.getSource();
        if (event.getSource() == buttonThree) {
            ButtonArray[0] = 0;
            ButtonArray[1] = 0;
            ButtonArray[2] = 1;
            ButtonArray[3] = 0;
            ButtonArray[4] = 0;
            System.out.println("Neutral");

        }
        // buttonFour = (JButton) event.getSource();
        if (event.getSource() == buttonFour) {
            ButtonArray[0] = 0;
            ButtonArray[1] = 0;
            ButtonArray[2] = 0;
            ButtonArray[3] = 1;
            ButtonArray[4] = 0;
            System.out.println("Sad");

        }

        // buttonFive = (JButton) event.getSource();
        if (event.getSource() == buttonFive) {
            ButtonArray[0] = 0;
            ButtonArray[1] = 0;
            ButtonArray[2] = 0;
            ButtonArray[3] = 0;
            ButtonArray[4] = 1;
            System.out.println("Very Sad");

        }

        // System.out.println(Arrays.toString(ButtonArray));
        // ImageIcon image = (imageList[i]);

    }

}

Answer 1

我真的不明白你们代码的大部分应该做什么。因此，这里有一个最小的示例，可以满足您的要求：一个标签和两个按钮，为该标签设置不同的图像。

ImageIcon[] images = new ImageIcon[] {
        new ImageIcon("foo.gif"),
        new ImageIcon("bar.gif"),
        new ImageIcon("blub.gif")
};

JFrame frame = new JFrame("Test");
frame.getContentPane().setLayout(new FlowLayout());

JLabel label = new JLabel(images[0]);
frame.getContentPane().add(label);

JButton button1 = new JButton("Image 1");
button1.addActionListener(e -> label.setIcon(images[0]));
frame.getContentPane().add(button1);

JButton button2 = new JButton("Image 2");
button2.addActionListener(e -> label.setIcon(images[1]));
frame.getContentPane().add(button2);

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

请注意，这是使用 Lambda 函数 (Java 8)，但您可以对一个或多个 "real" ActionListener classes 执行相同的操作。重要的是你打电话给 label.setIcon(theImage);您的代码中似乎缺少这部分内容。

如果您想循环浏览图片列表或图片数组，可以这样做：

AtomicInteger index = new AtomicInteger(0);
JButton buttonCycle = new JButton("Cycle");
buttonCycle.addActionListener(e -> label.setIcon(images[index.getAndIncrement() % images.length]));
frame.getContentPane().add(buttonCycle);

此处使用了 AtomicInteger，因此我可以将其声明为局部变量并在 lambda 中使用它。如果您将其作为周围 class.

的成员变量，您也可以使用常规 int

private int c = 0;
...
buttonCycle.addActionListener(e -> label.setIcon(images[c++ % images.length]));

要点是：创建一个计数器变量，每次调用按钮时递增它，并将标签的图标设置为具有该计数的元素，模块数组的大小。

按下 JButton 时尝试更改图像

Trying to change image when JButton pressed

java

image

jpanel

jbutton

imageicon