в 17:44, 31 мая 2010

2010-05-31T17:44:27Z

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== A corner component is displayed only if the two components at a right angle from the corner are currently shown. ==



<source lang="java">
import java.awt.BorderLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
public class JScrollPaneHeadersandCorners {
public static void main(String args[]) {
final Object rows[][] = { { "one", "1" }, { "two", "2" }, { "three", "3" }, { "four", "4" },
};
final Object headers[] = { "English", "#" };
JFrame frame = new JFrame("Table Printing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
final JTable table = new JTable(rows, headers);
JScrollPane scrollPane = new JScrollPane(table);
frame.add(scrollPane, BorderLayout.CENTER);
scrollPane.setCorner(JScrollPane.UPPER_RIGHT_CORNER, new JButton("..."));
frame.setSize(300, 150);
frame.setVisible(true);
}
}</source>



== Add component to JScrollPane ==



<source lang="java">
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JScrollPane;
import javax.swing.border.LineBorder;
public class AddingToJScrollPane {
public static void main(String args[]) {
JFrame frame = new JFrame("Tabbed Pane Sample");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JLabel label = new JLabel("Label");
label.setPreferredSize(new Dimension(1000, 1000));
JScrollPane jScrollPane = new JScrollPane(label);
JButton jButton1 = new JButton();
jScrollPane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
jScrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
jScrollPane.setViewportBorder(new LineBorder(Color.RED));
jScrollPane.getViewport().add(jButton1, null);
frame.add(jScrollPane, BorderLayout.CENTER);
frame.setSize(400, 150);
frame.setVisible(true);
}
}</source>



== Adding component to JScrollPane using its constructor ==



<source lang="java">
import java.awt.BorderLayout;
import java.awt.Dimension;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JScrollPane;
public class AddingToJScrollPane {
public static void main(String args[]) {
JFrame frame = new JFrame("Tabbed Pane Sample");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JLabel label = new JLabel("Label");
label.setPreferredSize(new Dimension(1000, 1000));
JScrollPane jScrollPane = new JScrollPane(label);
frame.add(jScrollPane, BorderLayout.CENTER);
frame.setSize(400, 150);
frame.setVisible(true);
}
}</source>



== Create a scrollable list ==



<source lang="java">
import javax.swing.JList;
import javax.swing.JScrollPane;
public class Main {
public static void main(String[] argv) throws Exception {
JList list = new JList();
JScrollPane scrollableList = new JScrollPane(list);
}
}</source>



== Customizing a JScrollPane Look and Feel ==

Property StringObject TypeScrollPane.actionMapActionMapScrollPane.ancestorInputMapInputMapScrollPane.ancestorInputMap.RightToLeftInputMapScrollPane.backgroundColorScrollPane.borderBorderScrollPane.fontFontScrollPane.foregroundColorScrollPane.viewportBorderBorderScrollPane.viewportBorderInsetsInsetsScrollPaneUIString

== Get the default scrollbar policy ==



<source lang="java">
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
public class Main {
public static void main(String[] argv) throws Exception {
JTextArea textArea = new JTextArea();
JScrollPane pane = new JScrollPane(textArea);
// Get the default scrollbar policy
int hpolicy = pane.getHorizontalScrollBarPolicy();
// JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED;
int vpolicy = pane.getVerticalScrollBarPolicy();
// JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED;
}
}</source>



== JScrollPane: display a large component within a smaller display area ==

Adding the component to a JViewport
Identifying the component to be scrolled can be done in one of two ways.



<source lang="java">
import java.awt.BorderLayout;
import java.awt.Dimension;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JScrollPane;
public class JScrollPaneViewport {
public static void main(String args[]) {
JFrame frame = new JFrame("Tabbed Pane Sample");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

JLabel label = new JLabel("Label");
label.setPreferredSize(new Dimension(1000,1000));
JScrollPane jScrollPane = new JScrollPane();
jScrollPane.setViewportView(label);
frame.add(jScrollPane, BorderLayout.CENTER);
frame.setSize(400, 150);
frame.setVisible(true);
}
}</source>



== JScrollPane Scrollbar Policies ==

Policy TypeDescriptionVERTICAL_SCROLLBAR_AS_NEEDEDDisplays designated scrollbar if viewport is too small to display its entire contentsHORIZONTAL_SCROLLBAR_AS_NEEDEDDisplays designated scrollbar if viewport is too small to display its entire contentsVERTICAL_SCROLLBAR_ALWAYSAlways displays designated scrollbarHORIZONTAL_SCROLLBAR_ALWAYSAlways displays designated scrollbarVERTICAL_SCROLLBAR_NEVERNever displays designated scrollbarHORIZONTAL_SCROLLBAR_NEVERNever displays designated scrollbar

== Listening for Scrollbar Value Changes in a JScrollPane Container ==



<source lang="java">
import java.awt.Adjustable;
import java.awt.event.AdjustmentEvent;
import java.awt.event.AdjustmentListener;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
public class Main {
public static void main(String[] argv) throws Exception {
JTextArea textArea = new JTextArea();
JScrollPane pane = new JScrollPane(textArea);
// Listen for value changes in the scroll pane"s scrollbars
AdjustmentListener listener = new MyAdjustmentListener();
pane.getHorizontalScrollBar().addAdjustmentListener(listener);
pane.getVerticalScrollBar().addAdjustmentListener(listener);
}
}
class MyAdjustmentListener implements AdjustmentListener {
public void adjustmentValueChanged(AdjustmentEvent evt) {
Adjustable source = evt.getAdjustable();
if (evt.getValueIsAdjusting()) {
return;
}
int orient = source.getOrientation();
if (orient == Adjustable.HORIZONTAL) {
System.out.println("from horizontal scrollbar");
} else {
System.out.println("from vertical scrollbar");
}
int type = evt.getAdjustmentType();
switch (type) {
case AdjustmentEvent.UNIT_INCREMENT:
System.out.println("Scrollbar was increased by one unit");
break;
case AdjustmentEvent.UNIT_DECREMENT:
System.out.println("Scrollbar was decreased by one unit");
break;
case AdjustmentEvent.BLOCK_INCREMENT:
System.out.println("Scrollbar was increased by one block");
break;
case AdjustmentEvent.BLOCK_DECREMENT:
System.out.println("Scrollbar was decreased by one block");
break;
case AdjustmentEvent.TRACK:
System.out.println("The knob on the scrollbar was dragged");
break;
}
int value = evt.getValue();
}
}</source>



== Make the scrollbars always appear ==



<source lang="java">
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
public class Main {
public static void main(String[] argv) throws Exception {
JTextArea textArea = new JTextArea();
JScrollPane pane = new JScrollPane(textArea);
pane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
pane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
}
}</source>



== Make the scrollbars never appear ==



<source lang="java">
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
public class Main {
public static void main(String[] argv) throws Exception {
JTextArea textArea = new JTextArea();
JScrollPane pane = new JScrollPane(textArea);
pane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
pane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_NEVER);
}
}</source>



== Resetting the Viewport Position: move JScrollPane to the top ==



<source lang="java">
import java.awt.event.*;
import javax.swing.*;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JScrollBar;
import javax.swing.JScrollPane;
class JScrollPaneToTopAction implements ActionListener {
JScrollPane scrollPane;
public JScrollPaneToTopAction(JScrollPane scrollPane) {
if (scrollPane == null) {
throw new IllegalArgumentException(
"JScrollPaneToTopAction: null JScrollPane");
}
this.scrollPane = scrollPane;
}
public void actionPerformed(ActionEvent actionEvent) {
JScrollBar verticalScrollBar = scrollPane.getVerticalScrollBar();
JScrollBar horizontalScrollBar = scrollPane.getHorizontalScrollBar();
verticalScrollBar.setValue(verticalScrollBar.getMinimum());
horizontalScrollBar.setValue(horizontalScrollBar.getMinimum());
}
}

public class JScrollPaneToTopActionDemo {
public static void main(String args[]) {
JFrame frame = new JFrame("Tabbed Pane Sample");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JLabel label = new JLabel("Label");
label.setPreferredSize(new Dimension(1000, 1000));
JScrollPane jScrollPane = new JScrollPane(label);
JButton bn = new JButton("Move");

bn.addActionListener(new JScrollPaneToTopAction(jScrollPane));

frame.add(bn, BorderLayout.SOUTH);
frame.add(jScrollPane, BorderLayout.CENTER);
frame.setSize(400, 150);
frame.setVisible(true);
}
}</source>



== Set Continuous Layout ==



<source lang="java">
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSplitPane;
public class Test extends JFrame {
public Test() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel1 = new JPanel(new GridLayout(1, 5));
for (int i = 0; i < 5; i++) {
panel1.add(new JLabel("Left " + i));
}
panel1.setPreferredSize(new Dimension(250, 50));
JPanel panel2 = new JPanel(new GridLayout(1, 5));
for (int i = 0; i < 5; i++) {
panel2.add(new JLabel("Right " + i));
}
panel2.setPreferredSize(new Dimension(250, 50));
final JSplitPane split = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT,
panel1, panel2);
split.setContinuousLayout(true);
getContentPane().add(split, BorderLayout.CENTER);
pack();
setSize(500, 100);
}
public static void main(String[] args) {
new Test().setVisible(true);
}
}</source>



== Set Row Header View ==



<source lang="java">
import java.awt.BorderLayout;
import java.awt.GridLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
public class JScrollPaneRowHeaderView extends JFrame {
public JScrollPaneRowHeaderView() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel = new JPanel(new GridLayout(5, 10));
for (int i = 0; i < 50; i++) {
panel.add(new JLabel(" Label " + i));
}
JScrollPane scrolled = new JScrollPane(panel);
scrolled.setRowHeaderView(new JLabel("Labels: "));
getContentPane().add(scrolled, BorderLayout.CENTER);
pack();
setSize(300, 100);
setVisible(true);
}
public static void main(String[] args) {
new JScrollPaneRowHeaderView();
}
}</source>



== Working with JScrollPane Headers and Corners ==

To place a component in one of the corners of the JScrollPane, call setCorner(String key, Component corner)
key is
<OL><LI>JScrollPane.LOWER_LEFT_CORNER,</LI><LI>JScrollPane.LOWER_RIGHT_CORNER,</LI><LI>JScrollPane.UPPER_LEFT_CORNER, or</LI><LI>JScrollPane.UPPER_RIGHT_CORNER.</LI></OL>



<source lang="java">
import java.awt.BorderLayout;
import java.awt.GridLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.ScrollPaneConstants;
import javax.swing.SwingUtilities;
public class MainClass {
public static void main(String[] a) {
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(new JScrollPaneDemo());
f.setSize(500, 500);
f.setVisible(true);
}
}
class JScrollPaneDemo extends JPanel {
public void init() {
try {
SwingUtilities.invokeAndWait(new Runnable() {
public void run() {
makeGUI();
}
});
} catch (Exception exc) {
System.out.println("Can"t create because of " + exc);
}
}
private void makeGUI() {
setLayout(new BorderLayout());
JPanel jp = new JPanel();
jp.setLayout(new GridLayout(20, 20));
int b = 0;
for (int i = 0; i < 20; i++) {
for (int j = 0; j < 20; j++) {
jp.add(new JButton("Button " + b));
++b;
}
}
int v = ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED;
int h = ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED;
JScrollPane jsp = new JScrollPane(jp, v, h);
add(jsp, BorderLayout.CENTER);
}
}</source>

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в 17:44, 31 мая 2010

Admin: 1 версия