Question

我有一个小问题 - 如何在主类中从其他类/文件/方法重新绘制JPanel？

故事是，我有一个Swing窗口，它有一个方法列表，通过浏览文件夹中的文件和类自动生成，并阅读方法及其描述（注释）。现在，问题在于，当出现一个类，一个方法需要绘制时，比方说，使用圆和线的太阳，然后我怎样才能让它出现在主窗口中？

我看了（阅读：谷歌搜索）周围，并发现JPanel应该很方便，但是从另一个类和方法绘制到它上面，不知道它们的名字是什么，他们什么时候会使用绘画，创建..困难。

我也在添加主要方法，如果它有用的话。

static int indez = 0;
    protected static JList list; 
    static boolean valitud = false;
    public static JTextArea txtala;
    public static JScrollPane scrl;
    public static JPanel pilt;
    static Map<Integer, String[]> info = new TreeMap<Integer, String[]>();
    static ArrayList<Integer> nrs = new ArrayList<Integer>();
    public static void main(String[] args){
        Iterator<Entry<Integer, String[]>> iterator;
        Entry<Integer, String[]> entry;
        Integer val = 0;

        JFrame f = new JFrame("Praktikumid");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setSize(750, 350);

        JPanel panel = new JPanel();
        pilt = new JPanel(){public void paintComponent(Graphics g) {
            super.paintComponent(g);
            g.drawString("This is my custom Panel!", 10, 20);
        }};

        pilt.setVisible(false);
        pilt.setPreferredSize(new Dimension(f.getWidth() - 200, f.getHeight() - 20));
        pilt.setBackground(Color.GRAY);

        GroupLayout layout = new GroupLayout(panel);
        panel.setLayout(layout);
        layout.setAutoCreateGaps(true);
        layout.setAutoCreateContainerGaps(true);

        ActionListener kuular = new ActionListener() {
            public void actionPerformed(ActionEvent tegu) {
                valitud = true;
                try {
                    praxStarter();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        };

        MouseListener hiir = new MouseListener() {  
            public void mouseClicked(MouseEvent e) {
                indez = list.getSelectedIndex();
            }
            @Override
            public void mouseEntered(MouseEvent e) {}
            @Override
            public void mouseExited(MouseEvent e) {}
            @Override
            public void mousePressed(MouseEvent e) {}
            @Override
            public void mouseReleased(MouseEvent e) {}  
        };  

        JLabel kiri = new JLabel("Vali hiirega ja vajuta nupule");

        ArrayList<String> selections = new ArrayList<String>();

        // Iterating over all the items in another method to get the modules

        list = new JList(selections.toArray());
        list.setSelectedIndex(0);
        list.addMouseListener(hiir);

        JScrollPane listScroller = new JScrollPane(list, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED, JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
        listScroller.setMinimumSize(new Dimension(200, 50));
        listScroller.setMaximumSize(new Dimension(200, f.getHeight() * 1000));

        JButton button = new JButton("Vali");
        button.setActionCommand(Integer.toString(list.getSelectedIndex()));
        button.addActionListener(kuular);

        Font font = new Font("Arial", Font.PLAIN, 12);
        txtala = new JTextArea("<-- Vali sealt");
        txtala.setEditable(false);
        txtala.setMargin(new Insets(5, 8, 0, 0));
        txtala.setFont(font);
        scrl = new JScrollPane(txtala, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED, JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
        scrl.setPreferredSize(new Dimension(f.getWidth() - 200, f.getHeight() - 20));

        pilt.setBackground(Color.PINK);
        pilt.setVisible(false);
        pilt.setPreferredSize(new Dimension(f.getWidth() - 200, f.getHeight() - 20));

        GroupLayout.ParallelGroup menu = layout.createParallelGroup();
        GroupLayout.SequentialGroup row = layout.createSequentialGroup();
        GroupLayout.SequentialGroup leftright = layout.createSequentialGroup();
        GroupLayout.ParallelGroup topdown = layout.createParallelGroup();
        GroupLayout.ParallelGroup dbl = layout.createParallelGroup();
        GroupLayout.ParallelGroup dblrow = layout.createParallelGroup();

        menu.addComponent(kiri);
        menu.addComponent(listScroller);
        menu.addComponent(button);
        leftright.addGroup(menu);
        dbl.addComponent(scrl);
        dbl.addComponent(pilt);
        leftright.addGroup(dbl);

        row.addComponent(kiri);
        row.addComponent(listScroller);
        row.addComponent(button);
        topdown.addGroup(row);
        dblrow.addComponent(scrl);
        dblrow.addComponent(pilt);
        topdown.addGroup(dblrow);

        layout.setHorizontalGroup(leftright);
        layout.setVerticalGroup(topdown);

        panel.setComponentZOrder(pilt, 1);
        panel.setComponentZOrder(scrl, 0);

        f.add(panel);
        //f.pack();
        f.setVisible(true);
    }

    public static void praxStarter()  throws Exception{
            // As a note - nrs is the holder for menu indexes
            // info is a Map of those same menu items 
            // And one entry in info is in the form of String[]{name, class.method}
        String[] tekst = new String[2];
        String kls, met;
        Method meetod;

        txtala.setText("");

        tekst = info.get(nrs.get(indez));
        kls = tekst[1].substring(0, tekst[1].indexOf("."));
        met = tekst[1].substring(tekst[1].indexOf(".") + 1, tekst[1].length());

        meetod = Class.forName(kls).getMethod(met);
        meetod.setAccessible(true);
        meetod.invoke(Class.forName(kls).newInstance());
    }

此外，这里将是一个类绘制（或试图绘制）的示例：

public class brush extends Applet {
public void paint(Graphics g) {
        int x0 = 150;
        int y0 = 150;
        int r = 100;
        int x, y;
        double t;

        int w = getWidth();
        int h = getHeight();

        x0 = w / 2;
        y0 = h / 2;

        g.setColor(Color.white);
        g.fillRect(0, 0, w, h);

        g.setColor(Color.black);

        for (t = -Math.PI; t < Math.PI; t = t + Math.PI / 16) {
            x = (int) (r * Math.cos(t) + x0);
            y = (int) (r * Math.sin(t) + y0);
            g.drawLine(x0, y0, x, y);
        }
    }
}

非常感谢您的回答和建议！

修改这是一个截图： Screenshots

左边是常规的打印文本屏幕模块。在右边是隐藏的文本部分，JPanel显示，JPanel从pilt = new JPanel()部分绘制，但在主类之外没有任何其他succsessful编辑。

编辑：我试图以多种方式进行绘制，尝试出现搜索解决方案，例如。

`txtala.setVisible(false);
scrl.setVisible(false);
pilt.setBorder(BorderFactory.createLineBorder(Color.BLACK));
pilt.setVisible(true);
//bi = new BufferedImage(pilt.getWidth() + 1000, pilt.getHeight() + 1000, BufferedImage.TYPE_INT_ARGB);
Graphics g = pilt.getGraphics();
g.setColor(Color.black);
g.drawLine(0, 0, 1000, 1000);
g.drawString("OLOLOLOLO!", 30, 50);
pilt.paint(g);
pilt.update(g);
//g.dispose();
//repaint();`

Answer 1

哦，所以我顺便说一句。我没有在主窗口中使用相同的窗格，而是创建了一个新的弹出框并将框架放入其中。我知道，这不是最好的解决方案，而是干草，总比没有好。如果我设法找到一种没有弹出窗口的方法，那么我将在这里发布。在那之前，祝你好运！

Java：从不同的类绘制到JPanel

1 个答案: