Java Reference
In-Depth Information
7
import
javax.swing.JScrollPane;
8
import
javax.swing.event.ListSelectionListener;
9
import
javax.swing.event.ListSelectionEvent;
10
import
javax.swing.ListSelectionModel;
11
12
public
class
ListFrame
extends
JFrame
13
{
14
private final
JList<String> colorJList;
// list to display colors
15
private
static final
String[] colorNames = {
"Black"
,
"Blue"
,
"Cyan"
,
16
"Dark Gray"
,
"Gray"
,
"Green"
,
"Light Gray"
,
"Magenta"
,
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"Orange"
,
"Pink"
,
"Red"
,
"White"
,
"Yellow"
};
18
private
static final
Color[] colors = {
Color.BLACK
,
Color.BLUE
,
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Color.CYAN
,
Color.DARK_GRAY
,
Color.GRAY
,
Color.GREEN
,
20
Color.LIGHT_GRAY
,
Color.MAGENTA
,
Color.ORANGE
,
Color.PINK
,
21
Color.RED
,
Color.WHITE
,
Color.YELLOW
};
22
23
// ListFrame constructor add JScrollPane containing JList to JFrame
24
public
ListFrame()
25
{
26
super
(
"List Test"
);
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setLayout(
new
FlowLayout());
28
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colorJList =
new
JList<String>(colorNames);
// list of colorNames
colorJList.setVisibleRowCount(
5
);
// display five rows at once
30
31
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// do not allow multiple selections
colorJList.setSelectionMode(
ListSelectionModel.SINGLE_SELECTION
);
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34
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// add a JScrollPane containing JList to frame
add(
new
JScrollPane(colorJList));
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37
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colorJList.addListSelectionListener(
39
new
ListSelectionListener()
// anonymous inner class
40
{
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// handle list selection events
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@Override
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public
void
valueChanged(ListSelectionEvent event)
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{
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getContentPane().setBackground(
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colors[
colorJList.getSelectedIndex()
]);
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}
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}
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);
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}
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}
// end class ListFrame
Fig. 12.23
|
JList
that displays a list of colors. (Part 2 of 2.)
1
// Fig. 12.24: ListTest.java
2
// Selecting colors from a JList.
3
import
javax.swing.JFrame;
4
Fig. 12.24
|
Selecting colors from a
JList
. (Part 1 of 2.)
