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Resizing BasicArrowButton

I'm trying to get a BasicArrowButton component to resize and can't get it to work for the life of me. The following code is a much simpler version of the problem, but still demonstrates what I'm trying to do. The button is in a JPanel with the panel's layout set to FlowLayout. It needs to resize while still remaining in the panel with the same layout. Thanks in advance, and sorry for bad formatting:
Main class:
package PackageMain;
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.WindowConstants;
public class Main {
public static JFrame frame = new JFrame("Window");
public static PanelOne p1;
public static PanelTwo p2;
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.setBounds(100, 100, 800, 600);
p1 = new PanelOne();
frame.setVisible(true);
} catch(Exception e){
}
}
});
}
}
Second Class:
package PackageMain;
import java.awt.Dimension;
import java.awt.FlowLayout;
import javax.swing.JPanel;
import javax.swing.plaf.basic.BasicArrowButton;
public class PanelOne{
public PanelOne(){
FlowLayout fl = new FlowLayout();
BasicArrowButton b1 = new BasicArrowButton(BasicArrowButton.WEST);
JPanel p1 = new JPanel();
p1.add(b1);
p1.setLayout(fl);
b1.setPreferredSize(new Dimension(100, 100)); //DOESN'T WORK!
Main.frame.add(p1);
}
}

The problem is that the class BasicArrowButton overrides the method getPreferredSize(). So you either need to use layout, which does not honor this method, or provide your own implementation for this method.
First proposal:
import java.awt.Dimension;
import java.awt.GridLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.WindowConstants;
import javax.swing.plaf.basic.BasicArrowButton;
public class BasicArrowButtonTest {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frm = new JFrame("Test arrow button");
JPanel p = new JPanel(new GridLayout(1, 1));
p.setPreferredSize(new Dimension(100, 100));
p.add(new BasicArrowButton(BasicArrowButton.WEST));
frm.add(p);
frm.pack();
frm.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frm.setLocationRelativeTo(null);
frm.setVisible(true);
}
});
}
}
Second proposal:
package org.swingsamples.label;
import java.awt.Dimension;
import java.awt.FlowLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.WindowConstants;
import javax.swing.plaf.basic.BasicArrowButton;
public class BasicArrowButtonTest {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frm = new JFrame("Test arrow button");
JPanel p = new JPanel(new FlowLayout());
BasicArrowButton btn = new BasicArrowButton(BasicArrowButton.WEST) {
#Override
public Dimension getPreferredSize() {
return new Dimension(100, 100);
}
};
p.add(btn);
frm.add(p);
frm.pack();
frm.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frm.setLocationRelativeTo(null);
frm.setVisible(true);
}
});
}
}

Reinitialise a jframe

I've a main frame on which there is a side panel with some buttons, and central panel used to display the tables and data generated from buttons on the side panel and its sub-panels
On the start my central panel is blank and I want it to always return to its initial state( blank ) after each click on a button before generating any data
I've use some sort of observer pattern (I'm not so experienced) but my problem is that the central panel must display data after clicks on some buttons that are on panels that also need a click on the side panel before to be generated
I've tried to make an executable example on the following classes, my real application displays some tables on the central panel and i send the models via the update method of the observers
hope its clear for you and I hope if you can really help me
1 - the main frame:
package tests;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class MainFrame extends JFrame implements MyObserver{
private SidePanel sidePanel;
private JPanel centralPanel;
private JFrame frame;
private JLabel title;
public MainFrame(){
frame = new JFrame("TEST");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.setLayout(new BorderLayout());
sidePanel = new SidePanel();
sidePanel.addObserver(this);
centralPanel = new JPanel();
title = new JLabel();
initialise(0);
frame.pack();
frame.setVisible(true);
frame.setLocationRelativeTo(null);
}
private void initialise(int i) {
if( i == 0){
centralPanel.setPreferredSize(new Dimension(400,300));
centralPanel.setBackground(Color.green);
title.setText("GREEN");
centralPanel.add(title, BorderLayout.CENTER);
frame.add(sidePanel, BorderLayout.WEST);
frame.add(centralPanel, BorderLayout.CENTER);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new MainFrame();
}
});
}
#Override
public void update(int color) {
if(color == 0){
centralPanel.setBackground(Color.yellow);
title.setText("YELLOW");
}else{
centralPanel.setBackground(Color.pink);
title.setText("PINK");
}
}
}
2 - The side Panel
package tests;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JPanel;
public class SidePanel extends JPanel implements MyObserver,MyObservable{
private JPanel panel;
private JButton test;
private MyObserver observer;
private ButtonPanel buttonPanel;
public SidePanel(){
panel = new JPanel();
panel.setPreferredSize(new Dimension(140, 300));
panel.setBackground(Color.blue);
panel.setLayout(new BoxLayout(panel, 0));
test = new JButton("Lunch buttons");
test.setPreferredSize(new Dimension(80,30));
buttonPanel = new ButtonPanel();
buttonPanel.addObserver(this);
test.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
buttonPanel.setVisible(true);
}
});
panel.add(Box.createVerticalGlue());
panel.add(test);
panel.add(Box.createVerticalGlue());
panel.setVisible(true);
this.add(panel, BorderLayout.CENTER);
}
#Override
public void addObserver(MyObserver obs) {
this.observer = obs;
}
#Override
public void updateObserver(MyObserver obs, int color) {
obs.update(color);
}
#Override
public void update(int color) {
updateObserver(observer, color);
}
}
3 - the buttons panel, generally the source of any data to be displayed on the central panel
package tests;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JPanel;
public class ButtonPanel extends JDialog implements MyObservable{
private JButton yellow;
private JButton orange;
private JPanel panel;
private MyObserver observer;
public ButtonPanel(){
panel = new JPanel();
panel.setPreferredSize(new Dimension(300, 40));
panel.setLayout(new FlowLayout());
this.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
this.setContentPane(panel);
yellow = new JButton("YELLOW");
yellow.setPreferredSize(new Dimension(100,30));
yellow.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
updateObserver(observer, 0);
}
});
orange = new JButton("ORANGE");
orange.setPreferredSize(new Dimension(100,30));
orange.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
updateObserver(observer, 1);
}
});
panel.add(yellow);
panel.add(orange);
pack();
setLocationRelativeTo(null);
}
#Override
public void addObserver(MyObserver obs) {
this.observer = obs;
}
#Override
public void updateObserver(MyObserver obs, int color) {
obs.update(color);
}
}
Finally, the customized observer and observable interfaces, note in the real app i use a table model not just an int - I'm not sure it's a good way -
package tests;
public interface MyObservable {
public void addObserver(MyObserver obs);
public void updateObserver(MyObserver obs, int color);
}
package tests;
public interface MyObserver {
public void update(int color);
}

CHANGED ANSWER:
In SidePanel.java add:
private MainFrame frame;
Then make your constructor take a MyFrame object as parameter. Do this:
public SidePanel(MainFrame frame){
this.frame = frame;
//rest not changed
//
}
Change the actionPerformed() of test button to:
test.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
buttonPanel.setVisible(true);
frame.initialise(0); // this line is added
}
});
In MainFrame.java:
Change sidePanel = new SidePanel(); to sidePanel = new SidePanel(this);
AND
Change private void initialise(int i) to public void initialise(int i)
This does what you are trying to achieve.

Sizing a JScrollPane to take into account windows taskbar [duplicate]

This question already has answers here:
Sizing a JScrollPane in a JTabbedPane in a JFrame
(2 answers)
Closed 8 years ago.
I am starting this new question because this question has been voted to close since it didnt have an MVCE.
I have included the question with an SSCCE now.
Please take a look at the below code
import javax.swing.*;
import java.awt.*;
public class ScrollPaneTest {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame=new JFrame();
frame.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
JTabbedPane tabbedPane=new JTabbedPane();
tabbedPane.addTab("Tab 1", new JScrollPane(getPanel()));
tabbedPane.addTab("Tab 2", new JScrollPane(getPanel()));
frame.setContentPane(tabbedPane);
frame.pack();
frame.setVisible(true);
}
private JPanel getPanel() {
JPanel panel=new JPanel();
Box box = Box.createVerticalBox();
for (int i = 1; i <= 100; i++) {
box.add(new JLabel("This is Label #" + i));
}
panel.add(box);
return panel;
}
});
}
}
When I run this code I get a frame shown as below
In the same code if I add a
frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
Then the frame comes above the task bar. I would like my JFrame to stop just above the taskbar of windows.

This is basically a little hacky.
What this does is uses the screen bounds minus it's insets to calculate not only the height of the window, but also the position to encourage the window to appear within the available desktop space.
The main reason for this, is I have my taskbar pinned to the top of my screen...
import java.awt.GraphicsConfiguration;
import java.awt.GraphicsDevice;
import java.awt.GraphicsEnvironment;
import java.awt.Insets;
import java.awt.Rectangle;
import java.awt.Toolkit;
import javax.swing.Box;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTabbedPane;
import javax.swing.SwingUtilities;
import javax.swing.WindowConstants;
public class ScrollPaneTest {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
JTabbedPane tabbedPane = new JTabbedPane();
tabbedPane.addTab("Tab 1", new JScrollPane(getPanel()));
tabbedPane.addTab("Tab 2", new JScrollPane(getPanel()));
frame.setContentPane(tabbedPane);
frame.pack();
Rectangle viewBounds = getScreenViewableBounds();
frame.setSize(frame.getWidth(), viewBounds.height);
frame.setLocation(viewBounds.x, viewBounds.y);
frame.setVisible(true);
}
private JPanel getPanel() {
JPanel panel = new JPanel();
Box box = Box.createVerticalBox();
for (int i = 1; i <= 100; i++) {
box.add(new JLabel("This is Label #" + i));
}
panel.add(box);
return panel;
}
});
}
public static Rectangle getScreenViewableBounds() {
GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
GraphicsDevice gd = ge.getDefaultScreenDevice();
Rectangle bounds = new Rectangle(0, 0, 0, 0);
if (gd != null) {
GraphicsConfiguration gc = gd.getDefaultConfiguration();
bounds = gc.getBounds();
Insets insets = Toolkit.getDefaultToolkit().getScreenInsets(gc);
bounds.x += insets.left;
bounds.y += insets.top;
bounds.width -= (insets.left + insets.right);
bounds.height -= (insets.top + insets.bottom);
}
return bounds;
}
}
You may also wish to consider using the Scrollable interface to restrict the viewable area, for example...
import java.awt.Dimension;
import java.awt.GraphicsConfiguration;
import java.awt.GraphicsDevice;
import java.awt.GraphicsEnvironment;
import java.awt.Insets;
import java.awt.Rectangle;
import java.awt.Toolkit;
import javax.swing.Box;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTabbedPane;
import javax.swing.Scrollable;
import javax.swing.SwingUtilities;
import javax.swing.WindowConstants;
public class ScrollPaneTest {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
JTabbedPane tabbedPane = new JTabbedPane();
tabbedPane.addTab("Tab 1", new JScrollPane(getPanel()));
tabbedPane.addTab("Tab 2", new JScrollPane(getPanel()));
frame.setContentPane(tabbedPane);
frame.pack();
frame.setVisible(true);
}
private JPanel getPanel() {
JPanel panel = new ScrollablePane();
Box box = Box.createVerticalBox();
for (int i = 1; i <= 100; i++) {
box.add(new JLabel("This is Label #" + i));
}
panel.add(box);
return panel;
}
});
}
public static class ScrollablePane extends JPanel implements Scrollable {
#Override
public Dimension getPreferredScrollableViewportSize() {
return new Dimension(200, 400);
}
#Override
public int getScrollableUnitIncrement(Rectangle visibleRect, int orientation, int direction) {
return 32;
}
#Override
public int getScrollableBlockIncrement(Rectangle visibleRect, int orientation, int direction) {
return 32;
}
#Override
public boolean getScrollableTracksViewportWidth() {
return false;
}
#Override
public boolean getScrollableTracksViewportHeight() {
return false;
}
}
}

Why can this code note be run as a JFrame?

I am trying to make an applet run as a JFrame. The code I have below is simple but should work. It will run as an JApplet but when I go to RUN AS --> nothing appears.
import java.awt.*;
import java.applet.Applet;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class LifeCycle extends Applet
{
private static final long serialVersionUID = 1L;
String output = "test";
String event;
public void init()
{
gui(); //I am not certain if this needs to be there.
event = "\nInitializing...";
printOutput();
}
public void start()
{
event = "\nStarting...";
printOutput();
}
public void stop()
{
event = "\nStopping...";
printOutput();
}
public void destroy()
{
event = "\nDestroying...";
printOutput();
}
private void printOutput()
{
System.out.println(event);
output += event;
repaint();
}
private void gui() {
JFrame f = new JFrame("Not resizable");
JPanel d = new JPanel();
// LifeCycle a = new LifeCycle();
// a.init();//not working
d.setLayout(new BorderLayout());
d.add(new JButton("a"));
d.add(new JButton("b"));
d.setBackground(Color.RED);
//f.add(new LifeCycle());
f.add(d);
f.setSize(545,340);
f.setResizable(false);
f.setLocationRelativeTo(null);
f.setTitle("Test");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//a.destroy();
}
public void paint(Graphics g)
{
System.out.println("Graphics Paint Method!");
g.drawString(output, 100, 100);
}
public static void main(String[] args) {
LifeCycle l = new LifeCycle();
l.gui();
}
}
I would like to see the code that should be changed, but I cannot seem to find why this will not work. I have added to buttons to the panel to be displayed.

Don't mix AWT (Applet) with Swing components. Stick with just Swing.
Gear your class towards creating JPanels. Then you can place it in a JApplet if you want an applet or a JFrame if you want a JFrame.
Read up on use of BorderLayout -- you're adding multiple components to the default BorderLayout.CENTER position, and only one component, the last one added, will show.
For example ...
LifeCycle2.java
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JPanel;
class LifeCycle2 {
private static final int GAP = 5;
private static final int PREF_W = 545;
private static final int PREF_H = 340;
private JPanel mainPanel = new JPanel() {
#Override
public Dimension getPreferredSize() {
return LifeCycle2.this.getPreferredSize();
}
};
public LifeCycle2() {
JPanel buttonPanel = new JPanel(new GridLayout(1, 0, GAP, 0));
buttonPanel.add(new JButton("A"));
buttonPanel.add(new JButton("B"));
buttonPanel.setOpaque(false);
JPanel flowLayoutPanel = new JPanel();
flowLayoutPanel.setOpaque(false);
flowLayoutPanel.add(buttonPanel);
mainPanel.setLayout(new BorderLayout());
mainPanel.setBorder(BorderFactory.createEmptyBorder(GAP, GAP, GAP, GAP));
mainPanel.setBackground(Color.red);
mainPanel.add(flowLayoutPanel, BorderLayout.NORTH);
}
public Dimension getPreferredSize() {
return new Dimension(PREF_W, PREF_H);
}
public JComponent getMainPanel() {
return mainPanel;
}
}
Show as a JFrame,
LifeCycleFrame.java
import javax.swing.*;
public class LifeCycleFrame {
private static void createAndShowGui() {
LifeCycle2 lifeCycle2 = new LifeCycle2();
JFrame frame = new JFrame("LifeCycleTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(lifeCycle2.getMainPanel());
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
Show as an applet,
LifeCycleApplet.java
import java.lang.reflect.InvocationTargetException;
import javax.swing.JApplet;
import javax.swing.SwingUtilities;
public class LifeCycleApplet extends JApplet {
#Override
public void init() {
try {
SwingUtilities.invokeAndWait(new Runnable() {
public void run() {
LifeCycle2 lifeCycle2 = new LifeCycle2();
getContentPane().add(lifeCycle2.getMainPanel());
}
});
} catch (InvocationTargetException | InterruptedException e) {
e.printStackTrace();
}
}
}

Add f.setVisible(true); to the end of the gui() method. Without this call your frame won't be shown.
Please read the "How to Make Frames" Tutorial

JSplitPane won't resize when I use java.awt.Canvas?

I have a simple example where I'm using java.awt.Canvas for components within a JSplitPane, and the JSplitPane won't allow adjustment. Could anyone explain why? (and more importantly, how to fix)
VerticalSplit.java:
import java.awt.BorderLayout;
import java.awt.Component;
import javax.swing.JPanel;
import javax.swing.JSplitPane;
abstract public class VerticalSplit {
public VerticalSplit(JPanel panel)
{
panel.setLayout(new BorderLayout());
JSplitPane jsp = new JSplitPane(JSplitPane.VERTICAL_SPLIT,
createComponent1(), createComponent2());
jsp.setResizeWeight(0.5);
panel.add(jsp, BorderLayout.CENTER);
}
abstract protected Component createComponent1();
abstract protected Component createComponent2();
}
CanvasTest1.java:
import java.awt.Canvas;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Graphics;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class CanvasTest1 extends VerticalSplit
{
static public class PlainCanvas extends Canvas
{
#Override public void paint(Graphics g)
{
Dimension d = getSize();
int h = getHeight();
int w = getWidth();
g.drawRect(0,0,w,h);
g.drawLine(0,0,w,h);
g.drawLine(0,h,w,0);
}
};
public CanvasTest1(JPanel panel) { super(panel); }
#Override protected Component createComponent1() {
return new PlainCanvas();
}
#Override protected Component createComponent2() {
return new PlainCanvas();
}
public static void main(String[] args) {
JPanel panel = new JPanel();
CanvasTest1 test = new CanvasTest1(panel);
JFrame frame = new JFrame(test.getClass().getName());
frame.setContentPane(panel);
frame.pack();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}

Changing from Canvas to JPanel (as #tulskiy suggested -- thanks!) made it work properly.