Java中swing组件的基本问题？

Question

在理解这个简单的代码方面，我的问题可能非常基础。我自己编写了这段代码，从这里和那里了解一些代码。我想逐行跟踪这段代码，看看每行的含义是什么？我在代码行之上添加了我的理解作为注释，它可能是错误的，或者其中一些标记为****意味着我只是不知道它意味着什么。如果你能在这里帮助我，那就太好了。谢谢

import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.text.ParseException;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class TestingSwingComponents {

    public TestingSwingComponents() {
        //Create a frame which is the window that pops up
        JFrame myframe = new JFrame();
        //*****
        myframe.getContentPane().setLayout(new BorderLayout());
        //set the frame size to be 600 X 600 size
        myframe.setSize(600, 600);

        // create Pane1
        JPanel myPanel = new JPanel();
        //set the Layout component of Panel, as how you would like it to be
        //here it is 2 rows and 15 columns
        myPanel.setLayout(new GridLayout(2, 15));
        //create a button with text in it
        JButton letterButton = new JButton("click Me");
        //add the created button component to the panel
        myPanel.add(letterButton);
        //******
        myframe.getContentPane().add(myPanel, BorderLayout.SOUTH);

        // create another panel
        JPanel panelFormat = new JPanel();
        //create a textfield
        JTextField txtfield = new JTextField();
        //create a label for the textfield
        JLabel label = new JLabel("Guesss");
        //set the layout type for this panel
        panelFormat.setLayout(new BorderLayout());
        //add label to panel
        panelFormat.add(label);
        //add textfield to panel
        panelFormat.add(txtfield);
        //I dont know the difference between the below two
        //BorderLayout.CENTER still does not center the panel in the frame, I dont know why
        myframe.getContentPane().add(panelFormat, BorderLayout.CENTER);
        myframe.add(panelFormat);

        // default settings
        myframe.setTitle("Get buttons");
        myframe.setVisible(true);
        myframe.setLocationRelativeTo(null);
        myframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    public static void main(String[] args) throws ParseException {
        new TestingSwingComponents();
    }
}

Answer 1

另一答案

Answer 2

另一答案