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How to change the background color of a JSpinner dependent on the current edited content of the field?

I have a GUI with a JSpinner using a SpinnerNumberModel using double values.
As soon as I change the content of the Editor of the JSpinner, I want the background to change to yellow (to show that the currently displayed value is not the one "saved" in the JSpinner respectively its Model.
If that content is not valid (e.g. out of the allowed range specified by my SpinnerNumberModel or a text as "abc") the background should change to red.
I tried to achieve what I want with a FocusListener already but yet have not been successful, also I am not sure if It could work anyway, as I need to check the content somewhere between focussing and defocussing.
I checked Tutorials for all Listeners that exist for Swing components, but could not find a right one that suits the job. (here I informed myself)
I am new to the concept of Listeners and would really appreciate any help that gets me closer to solving the problem but also helps generally understanding Listeners and how to use them in this context better!
My really basic code example with the mentioned poor attempt using a focus listener:
public class test implements FocusListener{
JFrame frame;
SpinnerNumberModel model;
JSpinner spinner;
JComponent comp;
JFormattedTextField field;
public test() {
JFrame frame = new JFrame("frame");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BoxLayout(frame.getContentPane(), BoxLayout.Y_AXIS));
model = new SpinnerNumberModel(0., 0., 100., 0.1);
spinner = new JSpinner(model);
comp = spinner.getEditor();
field = (JFormattedTextField) comp.getComponent(0);
field.addFocusListener(this);
frame.getContentPane().add(spinner);
frame.getContentPane().add(new JButton("defocus spinner")); //to have something to defocus when testing :)
frame.pack();
frame.setVisible(true);
}
#Override
public void focusGained(FocusEvent e) {
// TODO Auto-generated method stub
//when the values of the field and the spinner don't match, the field should get yellow
if(!field.getValue().equals(spinner.getModel().getValue())) {
field.setBackground(Color.YELLOW);
}
}
#Override
public void focusLost(FocusEvent e) {
// TODO Auto-generated method stub
//if they match again, reset to white
if(!field.getValue().equals(spinner.getModel().getValue())) {
field.setBackground(Color.RED);
}
}
}

A JSpinner uses a text field as the editor for the spinner
So, you can add a DocumentListener to the Document of the text field that is used as the editor.
Something like:
JTextField textField = ((JSpinner.DefaultEditor)spinner.getEditor()).getTextField());
textField.getDocument.addDocumentListener(...);
Then when text is added/removed a DocumentEvent will be generated and you can do your error checking. Read the section from the Swing tutorial on Listener For Changes on a Document for more information and working examples.

You can use CaretListener , here is a start:
import java.awt.Color;
import java.awt.Component;
import javax.swing.BoxLayout;
import javax.swing.JFormattedTextField;
import javax.swing.JFrame;
import javax.swing.JSpinner;
import javax.swing.SpinnerNumberModel;
import javax.swing.event.CaretEvent;
import javax.swing.event.CaretListener;
public class SpinerTest{
JSpinner spinner;
public SpinerTest() {
JFrame frame = new JFrame("frame");
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(300, 200);
frame.setLayout(new BoxLayout(frame.getContentPane(), BoxLayout.Y_AXIS));
SpinnerNumberModel model = new SpinnerNumberModel(0., 0., 100., 0.1);
spinner = new JSpinner(model);
setCaretListener();
frame.getContentPane().add(spinner);
frame.pack();
frame.setVisible(true);
}
private void setCaretListener() {
for(Component c : spinner.getEditor().getComponents()) {
JFormattedTextField field =(JFormattedTextField) c;
field.addCaretListener(new CaretListener(){
#Override
public void caretUpdate(CaretEvent ce) {
if (field.isEditValid()) {
//add aditional test as needed
System.out.println("valid Edit Entered " + field.getText());
field.setBackground(Color.WHITE);
}
else {
System.out.println("Invalid Edit Entered" + field.getText());
field.setBackground(Color.PINK);
}
}
});
}
}
public static void main(String[] args) {
new SpinerTest();
}
}

I was able to fulfill the task with a combination of a KeyListener, a DocumentListener and a FocusListener. The solution might not be the easiest, but finally I coded sth. that works. Comments in the file appended should explain how I dealt with the problem.
I expanded the original task with a CommaReplacingNumericDocumentFilter expands DocumentFilter class that was not written by me, I got the code from my professor and edited it to my needs only. Now only digits, minus and e, E are accepted as entries in the JSpinner.
Commas are replaced with dots also.
Code:
import java.awt.*;
import java.awt.event.*;
import java.util.Locale;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
public class test implements DocumentListener, ChangeListener, KeyListener{
boolean keyPressed;
JFrame frame;
SpinnerNumberModel model;
JSpinner spinner;
JComponent comp;
JFormattedTextField field;
public test() {
JFrame frame = new JFrame("frame");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BoxLayout(frame.getContentPane(), BoxLayout.Y_AXIS));
model = new SpinnerNumberModel(0., 0., 100000., .1);
spinner = new JSpinner(model);
//disable grouping for spinner
JSpinner.NumberEditor editor = new JSpinner.NumberEditor(spinner);
editor.getFormat().setGroupingUsed(false);
spinner.setEditor(editor);
comp = spinner.getEditor();
field = (JFormattedTextField) comp.getComponent(0);
field.getDocument().addDocumentListener(this);
field.addKeyListener(this);
spinner.addChangeListener(this);
frame.getContentPane().add(spinner);
frame.pack();
frame.setVisible(true);
}
#Override
public void insertUpdate(DocumentEvent e) {
DocumentEventHandler(e);
}
#Override
public void removeUpdate(DocumentEvent e) {
DocumentEventHandler(e);
}
#Override
public void changedUpdate(DocumentEvent e) {
DocumentEventHandler(e);
}
public static boolean isNumeric(String str)
{
try
{
double d = Double.parseDouble(str);
}
catch(NumberFormatException nfe)
{
return false;
}
return true;
}
public static void main(String[] args) {
//to get the right format for double precision numbers
Locale.setDefault(Locale.US);
test test = new test();
}
#Override
public void stateChanged(ChangeEvent e) {
System.out.println("valuechanged: " + spinner.getValue().toString());
if(keyPressed) {
field.setBackground(Color.WHITE);
}
keyPressed = false;
}
public void DocumentEventHandler(DocumentEvent e) {
//as soon as update is inserted, set background to yellow
if (keyPressed) {
field.setBackground(Color.YELLOW);
//check if input is numeric and in bounds
String text = field.getText();
if (isNumeric(text)) {
double value = Double.parseDouble(text);
if (value < (Double)model.getMinimum() || value > (Double)model.getMaximum()) {
field.setBackground(Color.RED);
}
}
else { //set background to red
field.setBackground(Color.RED);
}
}
keyPressed = false;
//System.out.println(e.toString());
//System.out.println("Text: " + field.getText());
}
#Override
public void keyTyped(KeyEvent e) {
// TODO Auto-generated method stub
}
#Override
public void keyReleased(KeyEvent e) {
// TODO Auto-generated method stub
}
/** If not done yet, replaces the DocumentFilter with one replacing commas by decimal points.
* This can't be done at the very beginning because the DocumentFilter would be changed to a
* javax.swing.text.DefaultFormatter$DefaultDocumentFilter when setting up the JSpinner GUI. */
public void keyPressed(KeyEvent e) {
PlainDocument document = (PlainDocument)(field.getDocument());
if(!(document.getDocumentFilter() instanceof CommaReplacingNumericDocumentFilter))
document.setDocumentFilter(new CommaReplacingNumericDocumentFilter());
/*Tell the other handlers that a key has been pressed and the change in the document does
* not come from using the JSpinner buttons or the MouseWheel.
*/
keyPressed = true;
}
}
/** A javax.swing.text.DocumentFilter that replaces commas to decimal points
* and ignores non-numeric characters except 'e' and 'E'. This is called before
* modi */
class CommaReplacingNumericDocumentFilter extends DocumentFilter {
#Override
public void insertString(FilterBypass fb, int offset, String text, AttributeSet attr)
throws BadLocationException {
text = filter(text);
if (text.length() > 0)
super.insertString(fb, offset, text, attr);
}
#Override
public void replace(FilterBypass fb, int offset, int length, String text,
AttributeSet attrs) throws BadLocationException {
text = filter(text);
if (text.length() > 0)
super.replace(fb, offset, length, text, attrs);
}
String filter(String text) {
return text.replace(',', '.').replaceAll("[^0-9eE.-]","");
}
}

How to remove (nuke) a javax.swing.box entirely?

I have a JPanel that currently has a swing.box in it, which in itself houses an arbitrary number of JButtons.
Now one of the JButtons has the ability to create a new JButton, which goes fine.
However, after creating said new button, I want the button to go in the list at the right position (alphabetically sorted) which also goes fine. I am however sure that it is never the last button as I add some standard buttons at the end.
Now the problem is that I cannot nuke the box that has said buttons in them after which I rebuild the box.
(also see https://github.com/Diamundo/PhotoSelectorSys/ButtonPanel.java and specifically at line 42, start of function initButtons() )
(problem I also have, is that I add buttons with a preferred size which does take effect if I put them straight in the panel, but not if I put them in the box... so if you have a solution which lets me delete all buttons instead of the box that's also very welcome :D )
package photoselectorsys;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.io.File;
import java.util.ArrayList;
import javax.swing.Box;
import javax.swing.JButton;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class ButtonPanel extends JPanel {
private AppFrame listener;
private String path;
private Box box;
public ButtonPanel(int width, int height){
setPreferredSize(new Dimension(width, height));
setVisible(true);
box = Box.createVerticalBox();
}
public void setPath(String path){
this.path = path;
initButtons();
// pushButtons();
this.revalidate();
}
/*public void pushButtons() {
for(JButton jb : buttons) { //buttons was an ArrayList of button names. Is now the box.
this.remove(jb); //remove the button from the panel.
}
for(JButton jb : buttons) { //buttons should be changed to the box
add(jb);
}
}*/
public void initButtons(){
/* if(box.hasButtons()) {
box.nuke();
box = new Box(..);
}
*/
JButton jb;
File directory = new File(path);
File[] listFiles = directory.listFiles();
ArrayList<String> btns = new ArrayList<>();
for (File file : listFiles) {
if (file.isDirectory()) {
btns.add(file.getName());
}
}
btns.add("Add a new Button");
btns.add("Rotate CW");
btns.add("Rotate CCW");
btns.add("Rotate 180*");
System.out.println("buttons " + btns.size());
if(btns.size() > 4) { //if there's at least one folder, size > 4. Else add one big button or ask to create subfolder
for(String btn : btns) {
jb = new JButton(btn);
jb.setFont(new Font("Arial", Font.PLAIN, 20));
jb.setPreferredSize(new Dimension(this.getWidth()-20, 40));
jb.setVisible(true);
jb.addMouseListener(new MouseListener() {
#Override
public void mouseClicked(MouseEvent arg0) {
onButtonPress((JButton) arg0.getSource());
}
#Override
public void mouseEntered(MouseEvent e) { /* unused */ }
#Override
public void mouseExited(MouseEvent e) { /* unused */ }
#Override
public void mousePressed(MouseEvent e) { /* unused */ }
#Override
public void mouseReleased(MouseEvent e) { /* unused */ }
});
/*box.*/add(jb);
}
} else {
// do add folder magic from the start.
jb = new JButton("Add a new Button");
jb.setFont(new Font("Arial", Font.PLAIN, 20));
jb.setPreferredSize(new Dimension(this.getWidth()-20, this.getHeight()-30));
jb.setSize(new Dimension(this.getWidth()-20, this.getHeight()));
jb.setVisible(true);
jb.addMouseListener(new MouseListener() {
#Override
public void mouseClicked(MouseEvent arg0) {
onButtonPress((JButton) arg0.getSource());
}
#Override
public void mouseEntered(MouseEvent e) { /* unused */ }
#Override
public void mouseExited(MouseEvent e) { /* unused */ }
#Override
public void mousePressed(MouseEvent e) { /* unused */ }
#Override
public void mouseReleased(MouseEvent e) { /* unused */ }
});
/*box.*/add(jb);
}
// add(box);
}
public void onButtonPress(JButton jb){
// not interesting for this question. See github for function.
}
public void addListener(AppFrame listener) {
this.listener = listener;
}
}

To change the buttons in your box you don't have to create a new box but rather do one of the following 2 things:
a) add the button at the correct position using box.add( button, index )
b) remove all buttons using box.removeAll() and (re)add the buttons as needed
I'd prefer variant a) but there might be cases where rebuilding the box contents from scratch might be the better way.
Normally that alone should be sufficient since the component should realize it's layout is invalid and needs to be recalculated. If this doesn't happen or you need to revalidate the parent container as well for some reason call the invalidate() method on the relevant component.

How to use the repaint method in Java Swing

I am very new to the Graphics portion of Java. I have created a frame and on it I have added a panel whose color has been set to Green. Now on clicking that panel I want to draw a circle using a test class's object called Mypanel. But it does not happen. Please guide !
import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JPanel;
class Mypanel extends JPanel
{
#Override
public void paintComponent(Graphics g)
{
g.drawOval(15, 15, 5, 5);
}
}
public class algo extends javax.swing.JFrame {
public algo() {
initComponents();
jPanel1.setBackground(Color.GREEN);
}
Mypanel p = new Mypanel() ;
private void jPanel1MouseClicked(java.awt.event.MouseEvent evt) {
p.repaint();
}
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new algo().setVisible(true);
}
});
}
}
If I were to guess I would say that I am not supposed to use the repaint method, but I was told that this was to be used.

That code as supplied would not compile. For better help sooner, post a Minimal, Complete, and Verifiable example or Short, Self Contained, Correct Example.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
class Mypanel extends JPanel {
boolean clicked = false;
Mypanel() {
setBackground(Color.GREEN);
MouseListener mouseListener = new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
clicked = true;
repaint();
}
};
this.addMouseListener(mouseListener);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(400, 100);
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
if (clicked) {
g.drawOval(15, 15, 50, 50);
}
}
}
public class algo extends JFrame {
public algo() {
initComponents();
pack();
//jPanel1.setBackground(Color.GREEN); ?!?
}
protected final void initComponents() {
add(new Mypanel());
}
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new algo().setVisible(true);
}
});
}
}

There are a few things to correct in your example...
When you create the frame (i.e. in the constructor) you'll want to call super(). This is the first thing the constructor has to do. Then, you'll probably want to set an initial width/height, and set the background color of the frame green.
You need to add a mouse listener so that the mouseClicked method is actually called. Then have it add the 'MyPanel' object to the frame, and call repaint.
I think that's roughly what you're going for.

How to display styled text in a JXEditorPane

I'm displaying some text in a JTextPane, with some syntax highlighting using an implementation of DefaultStyledDocument. This works.
Now I wanted to add a search (ctrl-F) functionality, and tried using a JXEditorPane from swingx instead of the JTextPane.
I'm doing:
p = new JXEditorPane();
p.setEditable(false);
p.setDocument(new MyStyledDocument());
p.getDocument().addDocumentListener( ... some callbacks ... );
My callbacks are called as expected. However, the text does not appear to be styled. Is this feasible ? (I noticed that only the doc in JTextPane talks about StyledDocument, the setDocument() from JTextComponent just talks about Document).
[edit] I reduced the code down to (sorry for the length, it's the best I could do):
MyStyledDocument.java:
package com.mydemo;
import java.awt.*;
import javax.swing.text.*;
public class MyStyledDocument extends DefaultStyledDocument {
private Style _style;
public MyStyledDocument() {
_style = addStyle("bluuuue", null);
StyleConstants.setBold(_style, true);
StyleConstants.setForeground(_style, new Color(0, 250, 255));
}
public synchronized void applyStyle() {
System.out.println("applyStyle");
setCharacterAttributes(0, getLength(), _style, true);
}
}
Gui.java:
package com.mydemo;
import org.jdesktop.swingx.JXEditorPane;
import javax.swing.*;
import javax.swing.event.*;
public class Gui extends JFrame {
private static final long serialVersionUID = 1L;
public Gui() {
super();
setSize(100, 100);
JEditorPane pane = new JTextPane(); // replace by new JXEditorPane() here
pane.setEditable(false);
pane.setDocument(new MyStyledDocument());
pane.getDocument().addDocumentListener(new DocumentListener() {
public void insertUpdate(DocumentEvent e) { applyStyleInNextTick(e); }
public void removeUpdate(DocumentEvent e) { applyStyleInNextTick(e); }
public void changedUpdate(DocumentEvent e) { /* Do NOT restyle here, as this gets triggered by styling */ }
private void applyStyleInNextTick(final DocumentEvent e) {
SwingUtilities.invokeLater(new Runnable() { public void run() {
((MyStyledDocument) e.getDocument()).applyStyle();
}});
}
});
pane.setText("FooBar");
this.setContentPane(pane);
}
public static void main(String[] args) {
Gui gui = new Gui();
gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
gui.setVisible(true);
}
}
By default, the text is colored in blue. Switching to using a JXEditorPane (1 statement change) gives the same thing with the text not colored.

MouseListener on button rendered on a JTree Row in Java

I'm blocked with a probelm about Java and the use of JTree:
I want to create a JTree with, node by node, some JButtons components (or Images, I don't mind), like in the following picture. It will be 3 or 4 buttons in the same row. I succeed to do that.
But where I'm blocked is when I want to add a mouselistener on each of this button to manage their tooltip or an action on them.
In fact the JTree component is most of the time used to manage the action on the full node, but not on its inside components.
I did a short code, in comparaison at the real big code I have to work in, to quickly test what I say:
import javax.imageio.ImageIO;
import javax.swing.*;
import javax.swing.tree.*;
import java.awt.event.*;
import java.awt.*;
import java.io.IOException;
import java.net.URL;
public class TreeWithPopup extends JPanel {
DefaultMutableTreeNode root, node1, node2, node3;
public TreeWithPopup() {
MyJTree tree;
root = new DefaultMutableTreeNode("root", true);
node1 = new DefaultMutableTreeNode("node 1", true);
node2 = new DefaultMutableTreeNode("node 2", true);
node3 = new DefaultMutableTreeNode("node 3", true);
root.add(node1);
node1.add(node2);
root.add(node3);
setLayout(new BorderLayout());
tree = new MyJTree(root);
tree.setCellRenderer(new PCellRenderer());
add(new JScrollPane((JTree) tree), "Center");
}
public Dimension getPreferredSize() {
return new Dimension(300, 300);
}
public static void main(String s[]) {
JFrame frame = new JFrame("Tree with button");
TreeWithPopup panel = new TreeWithPopup();
frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
frame.setForeground(Color.black);
frame.setBackground(Color.lightGray);
frame.getContentPane().add(panel, "Center");
frame.setSize(panel.getPreferredSize());
frame.setVisible(true);
frame.addWindowListener(new WindowCloser());
}
}
class WindowCloser extends WindowAdapter {
public void windowClosing(WindowEvent e) {
Window win = e.getWindow();
win.setVisible(false);
System.exit(0);
}
}
class MyJTree extends JTree implements ActionListener {
MyJTree(DefaultMutableTreeNode dmtn) {
super(dmtn);
addMouseListener(new MouseListener() {
public void mouseClicked(MouseEvent arg0) {
System.out.println("JTree.MouseListener");
}
public void mouseEntered(MouseEvent arg0) {
System.out.println("JTree.MouseListener");
}
public void mouseExited(MouseEvent arg0) {
System.out.println("JTree.MouseListener");
}
public void mousePressed(MouseEvent arg0) {
System.out.println("JTree.MouseListener");
}
public void mouseReleased(MouseEvent arg0) {
System.out.println("JTree.MouseListener");
}
});
}
public void actionPerformed(ActionEvent ae) {
System.out.println("MyJTree.ActionPerformed");
}
}
class PCellRenderer extends DefaultTreeCellRenderer {
public Component getTreeCellRendererComponent(JTree ptree, Object pvalue, boolean psel, boolean pexpanded, boolean pleaf, int prow,
boolean phasFocus) {
Box myPanel = new Box(BoxLayout.X_AXIS);
JButton myButton = new JButton("test");
Image imgToUse = null;
Image imgRollOver = null;
try {
URL urlIcon = new URL("file:///C:/1.jpg"); // <===== change their the path to icons
imgToUse = ImageIO.read(urlIcon);
urlIcon = new URL("file:///C:/2.jpg"); // <===== change their the path to icons
imgRollOver = ImageIO.read(urlIcon);
} catch (IOException e) {
e.printStackTrace();
}
myButton.setRolloverIcon(new ImageIcon(imgRollOver));
myButton.setIcon(new ImageIcon(imgToUse));
myButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
System.out.println(" detected on ");
}
});
myButton.addMouseListener(new MouseListener() {
public void mouseClicked(MouseEvent arg0) {
System.out.println("myButton.MouseListener");
}
public void mouseEntered(MouseEvent arg0) {
System.out.println("myButton.MouseListener");
}
public void mouseExited(MouseEvent arg0) {
System.out.println("myButton.MouseListener");
}
public void mousePressed(MouseEvent arg0) {
System.out.println("myButton.MouseListener");
}
public void mouseReleased(MouseEvent arg0) {
System.out.println("myButton.MouseListener");
}
});
myPanel.add(myButton);
return myPanel;
}
}
You just have to change the icon path or put the two following icons at "c:/"
I also searched to use the x/y position of the row event but I was unable to find the position of my button after rendering.
If anyone can have an idea how to do that, he could be very helpful.
Thanks, at least for read this question ;-)

Tooltip support is actually provided by the TableCellRenderer directly. Your TableCellRenderer is a little muddled. It extends from DefaultTreeCellRenderer but makes no use of any of it's features, instead creating a new Box, JButton and loading icons each time a cell is rendered...
This is going to increase your memory usage a slow you application down...
Instead, try something like...
class PCellRenderer extends Box implements TreeCellRenderer {
private Image imgToUse = null;
private Image imgRollOver = null;
public PCellRenderer() {
super(BoxLayout.X_AXIS);
JButton myButton = new JButton("test");
try {
URL urlIcon = new URL("file:///C:/1.jpg"); // <===== change their the path to icons
imgToUse = ImageIO.read(urlIcon);
urlIcon = new URL("file:///C:/2.jpg"); // <===== change their the path to icons
imgRollOver = ImageIO.read(urlIcon);
} catch (IOException e) {
e.printStackTrace();
}
myButton.setRolloverIcon(new ImageIcon(imgRollOver));
myButton.setIcon(new ImageIcon(imgToUse));
add(myButton);
}
public Component getTreeCellRendererComponent(JTree ptree, Object pvalue, boolean psel, boolean pexpanded, boolean pleaf, int prow,
boolean phasFocus) {
// set the tooltip text here...
// Maybe change the icon...
return this;
}
}
Now, actually doing something...
Renderers are rubber stamps. That are not actually life components. Think of them like photos. You can take a snap shot of your friends, but you can't interact with them...same thing here...
Your idea of a MouseListener on the JTree is a correct one, in fact the JavaDocs actually have a demonstration of this...
public void mousePressed(MouseEvent e) {
int selRow = tree.getRowForLocation(e.getX(), e.getY());
TreePath selPath = tree.getPathForLocation(e.getX(), e.getY());
if(selRow != -1) {
if(e.getClickCount() == 1) {
mySingleClick(selRow, selPath);
}
else if(e.getClickCount() == 2) {
myDoubleClick(selRow, selPath);
}
}
}