我的组件不会显示在JFrame上，以及如何隐藏另一个框架

Question

So I'm trying to copy the layout of this website.

Website Pinterest Log In

Here's some what I have already done. I'm using "null" for my layout. I also put an actionlistener on my button which shows another frame.

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class Frame {



public static void main (String [] args) {

    JFrame frame = new JFrame("Pinterest");
    frame.setVisible(true);
    frame.setSize(1300,750);


    JPanel panel = new JPanel();
    frame.add(panel);

    JLabel name = new JLabel("Log in to Pinterest");
    name.setBounds(500, 96, 300, 100);
    name.setFont(new Font("Tahoma", Font.PLAIN, 28));

    JTextField text1 = new JTextField(15);
    text1.setBounds(500, 450, 300, 40);

    JTextField text2 = new JTextField(15);
    text2.setBounds(500, 350, 300, 40);

    JButton button = new JButton("Log In");
    button.setBounds(560,550, 200,30 );

    panel.setLayout(null);
    panel.add(name);
    panel.add(text1);
    panel.add(text2);
    panel.add(button);
    button.addActionListener(new Action1());

}
static class Action1 implements ActionListener
    {
public void actionPerformed(ActionEvent e)
{


JFrame frame2=  new JFrame("Pinterest");
frame2.setVisible(true);
frame2.setSize(1300,750);



 }}

Every time I would run this in my JCreator it would only show my frame. Then I have to maximize it to view the components but after I maximize it then minimize it doesn't hide anymore.

After I maximize the frame.

What is wrong with my code? Does my code works on yours smoothly? does it shows? How can I hide the first frame after clicking the button?

I'm having a hard time putting icon on the frame too.

Thanks for the help.

Answer 1

There are a number of basic mistakes

• null layouts. Avoid using null layouts, pixel perfect layouts are an illusion within modern ui design. There are too many factors which affect the individual size of components, none of which you can control. Swing was designed to work with layout managers at the core, discarding these will lead to no end of issues and problems that you will spend more and more time trying to rectify
• Making the frame visible before you've finished updating the UI. In most cases this can be fixed with revalidate , but since that causes the layout managers to recalculate their layouts, it's pointless when you're using null layouts

The simple answer is, use layout managers. The longer answer is more complicated.

You have three distinct areas, the "login with" group, the "field" group and (what I like to term) the "action" group. Each of these have there own requirements and functionality, it's best to try a seperate them if you can.

This will allow to apply functionality to each group or class which is unique to that group/class and reduce a lot of management head aches

The following examples focus on the layout, it does not focus on how you would then connect the functionality, this would be achieved simply through the use of an Observer Pattern , perhaps like ActionListener

import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Font;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JSeparator;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.EmptyBorder;

public class Test {

    public static void main(String[] args) {
        new Test();
    }

    public Test() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.add(new LoginPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class LoginPane extends JPanel {

        public LoginPane() {
            setBackground(Color.WHITE);
            setLayout(new GridBagLayout());
            GridBagConstraints gbc = new GridBagConstraints();
            gbc.gridwidth = GridBagConstraints.REMAINDER;
            gbc.weightx = 1;
            gbc.fill = GridBagConstraints.HORIZONTAL;
            gbc.insets = new Insets(4, 20, 4, 20);

            JLabel title = new JLabel("Log in to Pinterest");
            title.setFont(title.getFont().deriveFont(Font.BOLD, 18f));
            title.setBorder(new EmptyBorder(10, 0, 10, 0));

            add(title, gbc);
            add(new GroupPane(), gbc);
            gbc.insets = new Insets(4, 0, 4, 0);
            add(new JSeparator(JSeparator.HORIZONTAL), gbc);
            gbc.insets = new Insets(4, 20, 4, 20);
            add(new FieldPane(), gbc);
            gbc.insets = new Insets(4, 0, 0, 0);
            add(new ActionPane(), gbc);
        }

    }

    public class GroupPane extends JPanel {

        public GroupPane() {
            setOpaque(false);
            JPanel fbPane = new JPanel();
            JPanel goPane = new JPanel();
            JPanel twPane = new JPanel();

            fbPane.setBackground(Color.RED);
            goPane.setBackground(Color.BLUE);
            twPane.setBackground(Color.CYAN);

            fbPane.add(makeLabel("Log in with Facebook"));
            goPane.add(makeLabel("Log in with Google"));
            twPane.add(makeLabel("Log in with Twitter"));

            setLayout(new GridBagLayout());
            GridBagConstraints gbc = new GridBagConstraints();
            gbc.gridwidth = GridBagConstraints.REMAINDER;
            gbc.weightx = 1;
            gbc.fill = GridBagConstraints.HORIZONTAL;
            gbc.insets = new Insets(4, 0, 4, 0);

            add(fbPane, gbc);
            add(goPane, gbc);
            add(twPane, gbc);
        }

        protected JLabel makeLabel(String text) {
            JLabel label = new JLabel(text);
            label.setForeground(Color.WHITE);
            label.setFont(label.getFont().deriveFont(Font.BOLD, 14f));
            return label;
        }

    }

    public class FieldPane extends JPanel {

        private JTextField email;
        private JPasswordField password;

        public FieldPane() {
            setOpaque(false);
            email = new JTextField(10);
            password = new JPasswordField(10);

            email.setBackground(new Color(225, 225, 225));
            password.setBackground(new Color(225, 225, 225));

            Font font = email.getFont().deriveFont(Font.PLAIN, 24f);
            email.setFont(font);
            password.setFont(font);

            setLayout(new GridBagLayout());
            GridBagConstraints gbc = new GridBagConstraints();
            gbc.gridwidth = GridBagConstraints.REMAINDER;
            gbc.weightx = 1;
            gbc.fill = GridBagConstraints.HORIZONTAL;
            gbc.insets = new Insets(4, 0, 4, 0);

            add(email, gbc);
            add(password, gbc);

            JLabel label = new JLabel("Are you a business? Get started here");
            label.setFont(label.getFont().deriveFont(Font.PLAIN, 10f));
            gbc.insets.left = 4;
            add(label, gbc);
        }

    }

    public class ActionPane extends JPanel {

        public ActionPane() {
            setBorder(new EmptyBorder(10, 20, 10, 20));
            setLayout(new GridBagLayout());
            GridBagConstraints gbc = new GridBagConstraints();
            gbc.gridx = 0;
            gbc.gridy = 0;
            gbc.weightx = 1;
            gbc.insets = new Insets(4, 4, 4, 4);
            gbc.anchor = GridBagConstraints.WEST;

            add(makeLabel("Forgot your password?"), gbc);
            gbc.gridy++;
            add(makeLabel("Sign up now"), gbc);

            gbc.gridx++;
            gbc.gridy = 0;
            gbc.gridheight = 2;
            gbc.ipady = 10;
            gbc.anchor = GridBagConstraints.EAST;
            JButton login = new JButton("Log in");
            add(login, gbc);
        }

        protected JLabel makeLabel(String text) {
            JLabel label = new JLabel(text);
            label.setForeground(Color.DARK_GRAY);
            return label;
        }

    }

}

Take a look at Laying Out Components Within a Container and How to Use GridBagLayout . The LoginPane could also make use of a GridLayout , see for more details