我使用GridBagLayout将JButton、JLabels和JTextFields对齐到登录表单中。但有时所有对象都会塞进一行。（并非总是随机发生，但经常无法忽略）。

这是我调整物体的方法

package test;

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

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;

public class ManagerMain {
    public static JFrame frame = new JFrame("this is a frame");
    private JLabel loginNameLB = new JLabel("username:");
    private JLabel loginPasswordLB = new JLabel("password:");
    private JTextField loginName = new JTextField();
    private JPasswordField loginPassword = new JPasswordField();
    private JButton loginBTN = new JButton("Login");
    private JButton loginCreateBTN = new JButton("Create An Account");
    private Container login = new Container();
    //login is a container
    public ManagerMain() {
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);


        frame.setLayout(new BorderLayout());
        login.setLayout(new GridBagLayout());
        GridBagConstraints gbc1 = new GridBagConstraints();
        gbc1.insets = new Insets(2, 2, 15, 15);
        gbc1.weightx = 1.0;
        gbc1.weightx = 1.0;
        //user name label
        gbc1.gridx = 0;
        gbc1.gridy = 0;
        gbc1.gridwidth = 1;
        gbc1.gridheight = 1;
        gbc1.fill = GridBagConstraints.VERTICAL;
        gbc1.fill = GridBagConstraints.HORIZONTAL;
        login.add(loginNameLB, gbc1);
        //user name text field
        gbc1.gridx = 1;
        gbc1.gridy = 0;
        gbc1.gridwidth = 2;
        gbc1.gridheight = 1;
        gbc1.fill = GridBagConstraints.VERTICAL;
        gbc1.fill = GridBagConstraints.HORIZONTAL;
        login.add(loginName, gbc1);
        //password label
        gbc1.gridx = 0;
        gbc1.gridy = 1;
        gbc1.gridwidth = 1;
        gbc1.gridheight = 1;
        gbc1.fill = GridBagConstraints.VERTICAL;
        gbc1.fill = GridBagConstraints.HORIZONTAL;
        login.add(loginPasswordLB, gbc1);
        //password text field
        gbc1.gridx = 1;
        gbc1.gridy = 1;
        gbc1.gridwidth = 2;
        gbc1.gridheight = 1;
        gbc1.fill = GridBagConstraints.VERTICAL;
        gbc1.fill = GridBagConstraints.HORIZONTAL;
        login.add(loginPassword, gbc1);
        //login button
        gbc1.gridx = 1;
        gbc1.gridy = 2;
        gbc1.gridwidth = 1;
        gbc1.gridheight = 1;
        gbc1.fill = GridBagConstraints.VERTICAL;
        gbc1.fill = GridBagConstraints.HORIZONTAL;
        login.add(loginBTN, gbc1);
        //create account button
        gbc1.gridx = 2;
        gbc1.gridy = 2;
        gbc1.gridwidth = 1;
        gbc1.gridheight = 1;
        gbc1.fill = GridBagConstraints.VERTICAL;
        gbc1.fill = GridBagConstraints.HORIZONTAL;
        login.add(loginCreateBTN, gbc1);
        frame.add(login, BorderLayout.CENTER);//add container to frame
    }
}

有什么建议吗？它看起来像什么/应该像什么的图像如下

有时它也这样做：