使组件对 GridBagLayout 中的 GridBagConstrains.fill 免疫
Make components immune to GridBagConstrains.fill in GridBagLayout
我有一个带有 GridBagLayout 的 Java swing GUI。我已设置 GridBagConstraints.fill = GridBagConstraints.BOTH 但不希望我的按钮或文本字段垂直调整大小。此外，我只想调整 JTextArea 的大小，并尝试为我不想放大的组件设置最大尺寸，但它不起作用。关于如何使 GBC.fill 仅适用于某些组件的任何想法？
可重现的例子：
public class Main {
static JFrame frame = new JFrame("Create New Entry");
static JPanel wrapper = new JPanel();
static JTextField title = new JTextField(20);
static JLabel titleLabel = new JLabel("Title");
static JTextField username = new JTextField(20);
static JLabel usernameLabel = new JLabel("Username");
static JTextField email = new JTextField(20);
static JLabel emailLabel = new JLabel("Email Address");
static JPasswordField password = new JPasswordField(20);
static JLabel passwordLabel = new JLabel("Password");
static JButton generatePassword = new JButton("Generate Password");
static JPasswordField confirmPassword = new JPasswordField();
static JLabel confirmPasswordLabel = new JLabel("Confirm Password");
static JToggleButton showPassword = new JToggleButton("Show Password");
static JButton submit = new JButton("Submit Entry");
static JLabel notesLabel = new JLabel("Notes");
static JTextArea textArea = new JTextArea(5, 0);
static JScrollPane scrollPane = new JScrollPane(textArea, JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
public static void main(String[] args) {
GridBagConstraints gbc = new GridBagConstraints();
wrapper.setLayout(new GridBagLayout());
gbc.gridwidth = GridBagConstraints.RELATIVE;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.insets = new Insets(10, 10, 10, 10);
gbc.weightx = 1;
gbc.weighty = 1;
gbc.gridwidth = 1;
gbc.gridx = 0;
gbc.gridy = 0;
wrapper.add(titleLabel, gbc);
gbc.gridx = 1;
gbc.gridwidth = 2;
wrapper.add(title, gbc);
gbc.gridwidth = 1;
gbc.gridx = 0;
gbc.gridy = 1;
wrapper.add(usernameLabel, gbc);
gbc.gridx = 1;
gbc.gridwidth = 2;
wrapper.add(username, gbc);
gbc.gridwidth = 1;
gbc.gridx = 0;
gbc.gridy = 2;
wrapper.add(emailLabel, gbc);
gbc.gridx = 1;
gbc.gridwidth = 2;
wrapper.add(email, gbc);
gbc.gridwidth = 1;
gbc.gridx = 0;
gbc.gridy = 3;
wrapper.add(passwordLabel, gbc);
gbc.gridx = 1;
wrapper.add(password, gbc);
gbc.gridx = 2;
wrapper.add(generatePassword, gbc);
gbc.gridwidth = 1;
gbc.gridx = 0;
gbc.gridy = 4;
wrapper.add(confirmPasswordLabel, gbc);
gbc.gridx = 1;
wrapper.add(confirmPassword, gbc);
gbc.gridx = 2;
wrapper.add(showPassword, gbc);
gbc.gridx = 0;
gbc.gridy = 5;
wrapper.add(notesLabel, gbc);
gbc.fill = GridBagConstraints.BOTH;
gbc.gridx = 1;
gbc.gridwidth = 2;
wrapper.add(scrollPane, gbc);
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.gridwidth = 3;
gbc.gridy = 6;
wrapper.add(submit, gbc);
password.setPreferredSize(new Dimension(300, 26));
confirmPassword.setPreferredSize(new Dimension(300, 26));
title.setPreferredSize(new Dimension(300, 26));
username.setPreferredSize(new Dimension(300, 26));
email.setPreferredSize(new Dimension(300, 26));
frame.add(wrapper);
frame.pack();
frame.setMinimumSize(frame.getSize());
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
Any ideas on how I can make the GBC.fill only applicable for some components?
是的。不要让所有组件都使用填充字段为 .BOTH 的 GridBagConstraints 对象。每个组件都应添加自己的 GBC 对象，并且要水平和垂直填充的组件应将填充 属性 设置为 .BOTH，而只应水平扩展的组件应使用 GBC 填充.HORIZONTAL 的字段。当我使用 GridBagLayout 时，我经常创建辅助方法来创建约束对象，这些方法根据传递给它们的参数知道要使用什么设置，我建议您考虑这样做。
正如 Abra 所提到的，是的，您可以通过根据需要更改一个或多个字段的设置来修改 GridBagConstraints (GBC) 对象，我有时也会这样做，但更多时候，我使用辅助方法来创建GBC 对象在运行中。这样对我来说效果更好。
例如：
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import javax.swing.*;
public class Main2 extends JPanel {
private static final long serialVersionUID = 1L;
private static final int FIELD_COLS = 20;
private static final int TA_ROWS = 10;
private static final int INGS_GAP = 10;
private JLabel titleLabel = new JLabel("Title");
private JLabel userNameLabel = new JLabel("Username");
private JLabel emailAddrLabel = new JLabel("EmailAddress");
private JLabel passwordLabel = new JLabel("Password");
private JLabel confirmPasswordLabel = new JLabel("Confirm Password");
private JLabel notesLabel = new JLabel("Notes");
private JTextField titleField = new JTextField(FIELD_COLS);
private JTextField userNameField = new JTextField(FIELD_COLS);
private JTextField emailField = new JTextField(FIELD_COLS);
private JPasswordField passwordField = new JPasswordField(FIELD_COLS);
private JPasswordField confirmPasswordField = new JPasswordField(FIELD_COLS);
private JTextArea NotesArea = new JTextArea(TA_ROWS, FIELD_COLS);
private JScrollPane textAreaScrollPane = new JScrollPane(NotesArea);
private JButton generatePasswordBtn = new JButton("Generate Password");
private JButton showPasswordBtn = new JButton("Show Password");
private JButton submitEntryBtn = new JButton("Submit Entry");
public Main2() {
setLayout(new GridBagLayout());
// basic GBC use
int row = 0;
GridBagConstraints gbc = createGbc(0, row, GridBagConstraints.HORIZONTAL);
add(titleLabel, gbc);
gbc = createGbc(1, row, GridBagConstraints.HORIZONTAL, 2, 1);
add(titleField, gbc);
row++;
gbc = createGbc(0, row, GridBagConstraints.HORIZONTAL);
add(userNameLabel, gbc);
gbc = createGbc(1, row, GridBagConstraints.HORIZONTAL, 2, 1);
add(userNameField, gbc);
row++;
gbc = createGbc(0, row, GridBagConstraints.HORIZONTAL);
add(emailAddrLabel, gbc);
gbc = createGbc(1, row, GridBagConstraints.HORIZONTAL, 2, 1);
add(emailField, gbc);
row++;
gbc = createGbc(0, row, GridBagConstraints.HORIZONTAL);
add(passwordLabel, gbc);
gbc = createGbc(1, row, GridBagConstraints.HORIZONTAL);
add(passwordField, gbc);
gbc = createGbc(2, row, GridBagConstraints.HORIZONTAL);
add(generatePasswordBtn, gbc);
row++;
gbc = createGbc(0, row, GridBagConstraints.HORIZONTAL);
add(confirmPasswordLabel, gbc);
gbc = createGbc(1, row, GridBagConstraints.HORIZONTAL);
add(confirmPasswordField, gbc);
gbc = createGbc(2, row, GridBagConstraints.HORIZONTAL);
add(showPasswordBtn, gbc);
// here we set the GBC weighty to non-0 value to allow vertical expansion
// of added components
row++;
int txtAreaRows = TA_ROWS;
gbc = createGbc(0, row, GridBagConstraints.HORIZONTAL);
gbc.anchor = GridBagConstraints.WEST;
gbc.weighty = 1.0;
add(notesLabel, gbc);
gbc = createGbc(1, row, GridBagConstraints.BOTH, 2, txtAreaRows);
gbc.weighty = 1.0;
add(textAreaScrollPane, gbc);
textAreaScrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
row += txtAreaRows;
gbc = createGbc(0, row, GridBagConstraints.HORIZONTAL);
add(new JLabel(""), gbc);
gbc = createGbc(1, row, GridBagConstraints.HORIZONTAL, 2, 1);
add(submitEntryBtn, gbc);
}
private static GridBagConstraints createGbc(int x, int y, int fill, int width, int height) {
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = x;
gbc.gridy = y;
gbc.gridwidth = width;
gbc.gridheight = height;
gbc.fill = fill;
// allow horizontal expansion *unless* at left-most position in row
gbc.weightx = x == 0 ? 0.0 : 1.0;
gbc.weighty = 0.0; // default to no vertical expansion
gbc.insets = new Insets(INGS_GAP, INGS_GAP, INGS_GAP, INGS_GAP);
return gbc;
}
private static GridBagConstraints createGbc(int x, int y, int fill) {
return createGbc(x, y, fill, 1, 1);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
Main2 mainPanel = new Main2();
JFrame frame = new JFrame("GUI");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
});
}
}
我有一个带有 GridBagLayout 的 Java swing GUI。我已设置 GridBagConstraints.fill = GridBagConstraints.BOTH 但不希望我的按钮或文本字段垂直调整大小。此外，我只想调整 JTextArea 的大小，并尝试为我不想放大的组件设置最大尺寸，但它不起作用。关于如何使 GBC.fill 仅适用于某些组件的任何想法？
可重现的例子：
public class Main {
static JFrame frame = new JFrame("Create New Entry");
static JPanel wrapper = new JPanel();
static JTextField title = new JTextField(20);
static JLabel titleLabel = new JLabel("Title");
static JTextField username = new JTextField(20);
static JLabel usernameLabel = new JLabel("Username");
static JTextField email = new JTextField(20);
static JLabel emailLabel = new JLabel("Email Address");
static JPasswordField password = new JPasswordField(20);
static JLabel passwordLabel = new JLabel("Password");
static JButton generatePassword = new JButton("Generate Password");
static JPasswordField confirmPassword = new JPasswordField();
static JLabel confirmPasswordLabel = new JLabel("Confirm Password");
static JToggleButton showPassword = new JToggleButton("Show Password");
static JButton submit = new JButton("Submit Entry");
static JLabel notesLabel = new JLabel("Notes");
static JTextArea textArea = new JTextArea(5, 0);
static JScrollPane scrollPane = new JScrollPane(textArea, JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
public static void main(String[] args) {
GridBagConstraints gbc = new GridBagConstraints();
wrapper.setLayout(new GridBagLayout());
gbc.gridwidth = GridBagConstraints.RELATIVE;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.insets = new Insets(10, 10, 10, 10);
gbc.weightx = 1;
gbc.weighty = 1;
gbc.gridwidth = 1;
gbc.gridx = 0;
gbc.gridy = 0;
wrapper.add(titleLabel, gbc);
gbc.gridx = 1;
gbc.gridwidth = 2;
wrapper.add(title, gbc);
gbc.gridwidth = 1;
gbc.gridx = 0;
gbc.gridy = 1;
wrapper.add(usernameLabel, gbc);
gbc.gridx = 1;
gbc.gridwidth = 2;
wrapper.add(username, gbc);
gbc.gridwidth = 1;
gbc.gridx = 0;
gbc.gridy = 2;
wrapper.add(emailLabel, gbc);
gbc.gridx = 1;
gbc.gridwidth = 2;
wrapper.add(email, gbc);
gbc.gridwidth = 1;
gbc.gridx = 0;
gbc.gridy = 3;
wrapper.add(passwordLabel, gbc);
gbc.gridx = 1;
wrapper.add(password, gbc);
gbc.gridx = 2;
wrapper.add(generatePassword, gbc);
gbc.gridwidth = 1;
gbc.gridx = 0;
gbc.gridy = 4;
wrapper.add(confirmPasswordLabel, gbc);
gbc.gridx = 1;
wrapper.add(confirmPassword, gbc);
gbc.gridx = 2;
wrapper.add(showPassword, gbc);
gbc.gridx = 0;
gbc.gridy = 5;
wrapper.add(notesLabel, gbc);
gbc.fill = GridBagConstraints.BOTH;
gbc.gridx = 1;
gbc.gridwidth = 2;
wrapper.add(scrollPane, gbc);
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.gridwidth = 3;
gbc.gridy = 6;
wrapper.add(submit, gbc);
password.setPreferredSize(new Dimension(300, 26));
confirmPassword.setPreferredSize(new Dimension(300, 26));
title.setPreferredSize(new Dimension(300, 26));
username.setPreferredSize(new Dimension(300, 26));
email.setPreferredSize(new Dimension(300, 26));
frame.add(wrapper);
frame.pack();
frame.setMinimumSize(frame.getSize());
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
Any ideas on how I can make the GBC.fill only applicable for some components?
是的。不要让所有组件都使用填充字段为 .BOTH 的 GridBagConstraints 对象。每个组件都应添加自己的 GBC 对象，并且要水平和垂直填充的组件应将填充 属性 设置为 .BOTH，而只应水平扩展的组件应使用 GBC 填充.HORIZONTAL 的字段。当我使用 GridBagLayout 时，我经常创建辅助方法来创建约束对象，这些方法根据传递给它们的参数知道要使用什么设置，我建议您考虑这样做。
正如 Abra 所提到的，是的，您可以通过根据需要更改一个或多个字段的设置来修改 GridBagConstraints (GBC) 对象，我有时也会这样做，但更多时候，我使用辅助方法来创建GBC 对象在运行中。这样对我来说效果更好。
例如：
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import javax.swing.*;
public class Main2 extends JPanel {
private static final long serialVersionUID = 1L;
private static final int FIELD_COLS = 20;
private static final int TA_ROWS = 10;
private static final int INGS_GAP = 10;
private JLabel titleLabel = new JLabel("Title");
private JLabel userNameLabel = new JLabel("Username");
private JLabel emailAddrLabel = new JLabel("EmailAddress");
private JLabel passwordLabel = new JLabel("Password");
private JLabel confirmPasswordLabel = new JLabel("Confirm Password");
private JLabel notesLabel = new JLabel("Notes");
private JTextField titleField = new JTextField(FIELD_COLS);
private JTextField userNameField = new JTextField(FIELD_COLS);
private JTextField emailField = new JTextField(FIELD_COLS);
private JPasswordField passwordField = new JPasswordField(FIELD_COLS);
private JPasswordField confirmPasswordField = new JPasswordField(FIELD_COLS);
private JTextArea NotesArea = new JTextArea(TA_ROWS, FIELD_COLS);
private JScrollPane textAreaScrollPane = new JScrollPane(NotesArea);
private JButton generatePasswordBtn = new JButton("Generate Password");
private JButton showPasswordBtn = new JButton("Show Password");
private JButton submitEntryBtn = new JButton("Submit Entry");
public Main2() {
setLayout(new GridBagLayout());
// basic GBC use
int row = 0;
GridBagConstraints gbc = createGbc(0, row, GridBagConstraints.HORIZONTAL);
add(titleLabel, gbc);
gbc = createGbc(1, row, GridBagConstraints.HORIZONTAL, 2, 1);
add(titleField, gbc);
row++;
gbc = createGbc(0, row, GridBagConstraints.HORIZONTAL);
add(userNameLabel, gbc);
gbc = createGbc(1, row, GridBagConstraints.HORIZONTAL, 2, 1);
add(userNameField, gbc);
row++;
gbc = createGbc(0, row, GridBagConstraints.HORIZONTAL);
add(emailAddrLabel, gbc);
gbc = createGbc(1, row, GridBagConstraints.HORIZONTAL, 2, 1);
add(emailField, gbc);
row++;
gbc = createGbc(0, row, GridBagConstraints.HORIZONTAL);
add(passwordLabel, gbc);
gbc = createGbc(1, row, GridBagConstraints.HORIZONTAL);
add(passwordField, gbc);
gbc = createGbc(2, row, GridBagConstraints.HORIZONTAL);
add(generatePasswordBtn, gbc);
row++;
gbc = createGbc(0, row, GridBagConstraints.HORIZONTAL);
add(confirmPasswordLabel, gbc);
gbc = createGbc(1, row, GridBagConstraints.HORIZONTAL);
add(confirmPasswordField, gbc);
gbc = createGbc(2, row, GridBagConstraints.HORIZONTAL);
add(showPasswordBtn, gbc);
// here we set the GBC weighty to non-0 value to allow vertical expansion
// of added components
row++;
int txtAreaRows = TA_ROWS;
gbc = createGbc(0, row, GridBagConstraints.HORIZONTAL);
gbc.anchor = GridBagConstraints.WEST;
gbc.weighty = 1.0;
add(notesLabel, gbc);
gbc = createGbc(1, row, GridBagConstraints.BOTH, 2, txtAreaRows);
gbc.weighty = 1.0;
add(textAreaScrollPane, gbc);
textAreaScrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
row += txtAreaRows;
gbc = createGbc(0, row, GridBagConstraints.HORIZONTAL);
add(new JLabel(""), gbc);
gbc = createGbc(1, row, GridBagConstraints.HORIZONTAL, 2, 1);
add(submitEntryBtn, gbc);
}
private static GridBagConstraints createGbc(int x, int y, int fill, int width, int height) {
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = x;
gbc.gridy = y;
gbc.gridwidth = width;
gbc.gridheight = height;
gbc.fill = fill;
// allow horizontal expansion *unless* at left-most position in row
gbc.weightx = x == 0 ? 0.0 : 1.0;
gbc.weighty = 0.0; // default to no vertical expansion
gbc.insets = new Insets(INGS_GAP, INGS_GAP, INGS_GAP, INGS_GAP);
return gbc;
}
private static GridBagConstraints createGbc(int x, int y, int fill) {
return createGbc(x, y, fill, 1, 1);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
Main2 mainPanel = new Main2();
JFrame frame = new JFrame("GUI");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
});
}
}