Java Reference
In-Depth Information
Fig. 22.20
|
GridBagLayout
with the weights set to zero.
1
// Fig. 22.21: GridBagFrame.java
2
// Demonstrating GridBagLayout.
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4
5
import
java.awt.GridBagLayout;
import
java.awt.GridBagConstraints;
import
java.awt.Component;
6
import
javax.swing.JFrame;
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import
javax.swing.JTextArea;
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import
javax.swing.JTextField;
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import
javax.swing.JButton;
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import
javax.swing.JComboBox;
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public
class
GridBagFrame
extends
JFrame
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{
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private final
GridBagLayout layout;
// layout of this frame
private final
GridBagConstraints constraints;
// layout's constraints
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16
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// set up GUI
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public
GridBagFrame()
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{
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super
(
"GridBagLayout"
);
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layout =
new
GridBagLayout();
setLayout(layout);
// set frame layout
constraints =
new
GridBagConstraints();
// instantiate constraints
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// create GUI components
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JTextArea textArea1 =
new
JTextArea(
"TextArea1"
,
5
,
10
);
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JTextArea textArea2 =
new
JTextArea(
"TextArea2"
,
2
,
2
);
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String[] names = {
"Iron"
,
"Steel"
,
"Brass"
};
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JComboBox<String> comboBox =
new
JComboBox<String>(names);
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JTextField textField =
new
JTextField(
"TextField"
);
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JButton button1 =
new
JButton(
"Button 1"
);
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JButton button2 =
new
JButton(
"Button 2"
);
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JButton button3 =
new
JButton(
"Button 3"
);
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// weightx and weighty for textArea1 are both 0: the default
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// anchor for all components is CENTER: the default
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constraints.fill =
GridBagConstraints.BOTH
;
addComponent(textArea1,
0
,
0
,
1
,
3
);
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Fig. 22.21
|
GridBagLayout
layout manager. (Part 1 of 2.)