---
category: swing
folder: NumericKeypad
title: JButton内に複数のJLabelをBorderLayoutで配置する
tags: [GridBagLayout, BorderLayout, JButton, LayoutManager]
author: aterai
pubdate: 2024-10-07T06:51:52+09:00
description: JLabelをBorderLayoutでJButton内に2つ配置したキーキャップを作成し、それをJPanel内にGridBagLayoutでテンキー状にレイアウトします。
image: https://drive.google.com/uc?id=10kZwvZ1VvIWSHcNZcCwCsdJ0nb_Mus-b
---
* Summary [#summary]
`JLabel`を`BorderLayout`で`JButton内`に`2`つ配置したキーキャップを作成し、それを`JPanel`内に`GridBagLayout`でテンキー状にレイアウトします。
#download(https://drive.google.com/uc?id=10kZwvZ1VvIWSHcNZcCwCsdJ0nb_Mus-b)
* Source Code Examples [#sourcecode]
#code(link){{
private static JButton makeButton(String... s) {
String key = s[0];
String sub = s.length > 1 ? s[1] : " ";
int gap = 2;
Border border = BorderFactory.createEmptyBorder(gap, gap, gap, gap);
JLabel l1 = new JLabel(key);
l1.setFont(l1.getFont().deriveFont(12f));
l1.setBorder(border);
JLabel l2 = new JLabel(sub);
l2.setFont(l2.getFont().deriveFont(9.5f));
l2.setBorder(border);
JButton button = new JButton() {
@Override public void updateUI() {
super.updateUI();
setLayout(new BorderLayout());
setMargin(border.getBorderInsets(this));
}
@Override public Dimension getPreferredSize() {
int sz = SIZE - gap * 2;
return new Dimension(sz, sz);
}
};
if (Objects.equals(key, sub)) {
button.add(l1);
} else {
button.add(l1, BorderLayout.NORTH);
button.add(l2, BorderLayout.SOUTH);
}
return button;
}
}}
* Explanation [#explanation]
- `JButton`でキーキャップを作成
-- `JButton#getPreferredSize()`をオーバーライドして指定したサイズの正方形になるよう設定
-- 文字列やアイコンなしの空`JButton`に`BorderLayout`を設定
--- キーキャップの印字を`2`つの`JLabel`で別々に作成して`JButton#add(..., BorderLayout.NORTH)`、`JButton#add(..., BorderLayout.SOUTH)`で`JButton`にレイアウト
- `JPanel`にキーキャップを配置してテンキーを作成
-- `JPanel`に`GridBagLayout`を設定
-- `GridBagConstraints.gridwidth`、`GridBagConstraints.gridheight`でキーキャップが占有する領域のセル行数、列数を指定して`JPanel`にレイアウト
-- [[GridBagLayoutを使ってJButtonをキーボード状に配置する>Swing/KeyboardLayout]]
#code{{
GridBagConstraints c = new GridBagConstraints();
c.insets = new Insets(1, 1, 1, 1);
c.fill = GridBagConstraints.BOTH;
c.gridx = 0;
c.gridy = 0;
JPanel panel = new JPanel(new GridBagLayout());
panel.add(makeButton("<html>Num<br>Lock"), c);
c.gridx = GridBagConstraints.RELATIVE;
panel.add(makeButton("/"), c);
panel.add(makeButton("*"), c);
panel.add(makeButton("-"), c);
c.gridx = 0;
c.gridy++;
panel.add(makeButton("7", "Home"), c);
c.gridx = GridBagConstraints.RELATIVE;
panel.add(makeButton("8", "↑"), c);
panel.add(makeButton("9", "PgUp"), c);
c.gridheight = 2;
panel.add(makeButton("+", "+"), c);
c.gridx = 0;
c.gridy++;
c.gridheight = 1;
panel.add(makeButton("4", "←"), c);
c.gridx = GridBagConstraints.RELATIVE;
panel.add(makeButton("5"), c);
panel.add(makeButton("6", "→"), c);
c.gridx = 0;
c.gridy++;
panel.add(makeButton("1", "End"), c);
c.gridx = GridBagConstraints.RELATIVE;
panel.add(makeButton("2", "↓"), c);
panel.add(makeButton("3", "PgDn"), c);
c.gridheight = 2;
JButton enter = makeButton("Enter", "Enter");
panel.add(enter, c);
EventQueue.invokeLater(() -> {
getRootPane().setDefaultButton(enter);
enter.requestFocusInWindow();
});
c.gridx = 0;
c.gridy++;
c.gridwidth = 2;
c.gridheight = 1;
panel.add(makeButton("0", "Insert"), c);
c.gridx = GridBagConstraints.RELATIVE;
c.gridwidth = 1;
panel.add(makeButton(".", "Delete"), c);
panel.setBorder(BorderFactory.createLineBorder(Color.WHITE));
}}
* Reference [#reference]
- [[GridBagLayoutを使ってJButtonをキーボード状に配置する>Swing/KeyboardLayout]]
- [[GridBagLayoutを使ってレンガ状に配置>Swing/BrickLayout]]
* コメント [#comment]
* Comment [#comment]
#comment
#comment