Windows alignment in SWING-based GUI - java

My goal is to display several views of one object. For each view I create a thread. Also, I have a class which controls those views, e.g. send a command to align them. However, it is not always I get correct alignment. So there is a data races, and I cannot understand what I am doing wrong.
Here there is a piece of code showing the problem I have. It has a simple idea: create a main view window, and then align the second window of the same size near its right border.
First, I have an abstract class to create a thread:
public abstract class ViewWindow implements Runnable{
private Thread thread;
private boolean terminate = false ;
private Controller controller;
private UpdateTask currentUpdateTask = null;
private class UpdateTask {
boolean alignWindows = true;
}
public ViewWindow(Controller controller, String title) {
this.title = title;
this.controller = controller;
}
public void startThread() {
thread = new Thread(this);
thread.start();
}
#Override
public void run() {
UpdateTask updateTask = null;
synchronized (thread) {
while (terminate == false) {
try {
thread.wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
updateTask = currentUpdateTask;
currentUpdateTask = null;
if(updateTask.alignWindows) {
controller.getLock().lock();
setLocationRelativeTo(controller.getMainWindow());
controller.getLock().unlock();
}
}
}
}
public void alignWindowsUsingThread() {
synchronized (thread) {
currentUpdateTask = new UpdateTask();
thread.notify();
}
}
public abstract void setLocationRelativeTo(ImageViewWindow imageWindow);
}
Then I extend it to create an abstraction for the window views:
public abstract class ImageViewWindow extends ViewWindow {
private JFrame frame;
public ImageViewWindow(Controller controller, String title) {
super(controller, title);
frame = new JFrame(title);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JLabel label = new JLabel(title);
frame.getContentPane().add(label, BorderLayout.CENTER);
frame.setPreferredSize(new Dimension(300,500));
frame.pack();
frame.setVisible(true);
}
public JFrame getFrame() {
return frame;
}
synchronized public void setLocation(int x, int y) {
frame.setLocation(x, y);
}
synchronized public Point getLocation() {
return frame.getLocation();
}
}
Finally, I override a function to set relative location for each window:
public class FirstWindow extends ImageViewWindow {
public FirstWindow(Controller controller, String title) {
super(controller, title);
this.setLocation(50, 50);
this.startThread();
}
#Override
public void setLocationRelativeTo(ImageViewWindow imageWindow) { }
}
public class SecondWindow extends ImageViewWindow {
public SecondWindow(Controller controller, String title) {
super(controller, title);
this.startThread();
}
#Override
public void setLocationRelativeTo(ImageViewWindow imageWindow) {
Point location = imageWindow.getLocation();
int xOffSet = imageWindow.getFrame().getWidth();
int yOffSet = 0;
this.setLocation(xOffSet + location.x, yOffSet + location.y);
}
}
Here there is a class which is responsible for the control:
public class Controller {
private Lock controlLock;
private List<ImageViewWindow> windows = new ArrayList<ImageViewWindow>();
private ImageViewWindow mainWindow;
public Controller() {
controlLock = new ReentrantLock();
}
public ImageViewWindow getMainWindow() {
return mainWindow;
}
public Lock getLock() {
return controlLock;
}
public void addMainWindow(ImageViewWindow mainViewWindow) {
this.mainWindow = mainViewWindow;
this.addWindow(mainViewWindow);
}
public void addWindow(ImageViewWindow imageWindow) {
windows.add(imageWindow);
}
public void updateWindowPositions() {
for(ImageViewWindow window : windows) {
window.alignWindowsUsingThread();
}
}
}
And do run everything:
public class Start {
public static void main(String[] args) {
Controller controller = new Controller();
ImageViewWindow window1 = new FirstWindow(controller, "FirstWindow");
controller.addMainWindow(window1);
ImageViewWindow window2 = new SecondWindow(controller, "SecondWindow");
controller.addWindow(window2);
controller.updateWindowPositions();
}
}
UPD: I updated the code based on the answer below, but the problem still remains!

You don’t specify how you want to “align” your windows but from your code
public void setLocationRelativeTo(ImageViewWindow imageWindow) {
Point location = imageWindow.getLocation();
int xOffSet = this.getFrame().getWidth();
int yOffSet = 0;
this.setLocation(xOffSet + location.x, yOffSet + location.y);
}
I suppose you want this to be placed to the right of imageWindow. In this case you have to use imageWindow.x + imageWindow.width rather than imageWindow.x + this.width:
| imageWindow | this
x ← width → x ← width →
↳=imageWindow.x+imageWindow.width
So the correct method would be:
public void setLocationRelativeTo(ImageViewWindow imageWindow) {
Point location = imageWindow.getLocation();
int xOffSet = imageWindow.getFrame().getWidth();
int yOffSet = 0;
this.setLocation(xOffSet + location.x, yOffSet + location.y);
}
By the way, I don’t get why you are making such a simple task that complicated and even multi-threaded. There’s no benefit from multi-threading here, only a complication that obstructs the view on the simplest things…

Related

problem with calling the method after pressing the key

I would like to implement KeyListiner so that when pressing Space key program would generate new object of Function class and draw new image representing this function. For now program is working but pressing space key does not allow to generate a new image. Every advice will be greatly appreciated :)
Main class:
public class Main {
public static void main(String[] args) {
JFrame window = new JFrame(SOFTWARE_TITLE);
MainView mainView = new MainView();
Key key = new Key();
Controller controller = new Controller(mainView);
key.setController(controller);
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
window.setSize(790, 580);
window.setLocationRelativeTo(null);
window.setResizable(false);
window.add(mainView);
window.setVisible(true);
}
}
MainView class:
public class MainView extends JPanel {
private Function function;
public MainView(){
super();
setBackground(Color.GRAY);
setLayout(null);
setSize(200, 200);
function = new Function();
DrawBoard drawBoard = new DrawBoard(function);
drawBoard.setSize(500, 500);
drawBoard.setBackground(Color.lightGray);
drawBoard.setLocation(250, 20);
add(drawBoard);
setVisible(true);
}
}
DrawBoard class:
public class DrawBoard extends Canvas {
short CUSTOM_WIDTH = 5 * 100;
private Function function;
public DrawBoard(Function function) {
this.function = function;
}
public void paint(Graphics g) {
double difference = function.getzMax() - function.getzMin();
for (int indexX = 0; indexX < 100; indexX++) {
for (int indexY = 0; indexY < 100; indexY++) {
double value = function.getPoints()[indexX][indexY].getZ() - function.getzMin();
double corrected = setFloatInRGBRange(difference, value);
g.setColor(intToColor((int) corrected));
g.fillRect(indexX * 5, CUSTOM_WIDTH - ((indexY+1) * 5), 5, 5);
}
}
}
public Color intToColor(int colNum){
return new Color(colNum, colNum, colNum);
}
private int setFloatInRGBRange(double difference, double value){
return (int) ((255 * value)/difference);
}
}
Key class:
public class Key implements KeyListener {
Controller controller;
public void setController(Controller controller) {
this.controller = controller;
}
#Override
public void keyTyped(KeyEvent e) {
}
#Override
public void keyPressed(KeyEvent e) {
}
#Override
public void keyReleased(KeyEvent e) {
if (e.getKeyChar() == KeyEvent.VK_SPACE){
controller.generateFormula();
}
}
}
Controller class:
public class Controller {
MainView mainView;
public Controller(MainView mainView) {
this.mainView = mainView;
}
public void generateFormula() {
this.mainView = new MainView();
}
}
There is some other things that need be reviewed in code you posted. But for your main concern i guess you donc check Key strokes properly.
I would use e.getKeyCode() instead of e.getKeyChar() to check the event.
So your condition would be : e.getKeyCode() == KeyEvent.VK_SPACE
it is out of topic, but :
Your use of Function in multiples classes is unnecessary. It could be used only in DrawBoard
Don't mix Swing and AWT components as other already advised

Observer Pattern on MVC for specific fields

On the MVC pattern, which is the best option for the Model to notify the View (if this is the right approach in the first place) where, from all the fields of data the Model is storing, only a couple of them are updated. Specifically when we only want to update specific fields of the View.
I am currently using a MVC pattern with Observer/Subscriber (JAVA Swing) as described here: https://stackoverflow.com/a/6963529 but when the Model updates, it changes everything in the View when the update() funcion is called, it's impossible to determine which field from the Model changed in order to update only the required field in the View.
I read this topic: https://softwareengineering.stackexchange.com/a/359008 and this as well: https://stackoverflow.com/a/9815189 which I think it's usefull, but for the later, I can't understand very well how can I set a propertyChangeListener on a variale (int, float, etc). Also related to this: https://stackoverflow.com/a/9815189
The Main class where the software start to run:
public class Main {
public static void main(String[] args) {
Model m = new Model();
View v = new View(m);
Controller c = new Controller(m, v);
c.initController();
}
}
So the code that I have on Model is this:
public class Model extends Observable {
//...
private float speed;
private int batteryPercentage;
public float getSpeed() {
return speed;
}
public void setSpeed(float speed) {
this.speed = speed;
setChanged();
notifyObservers();
}
public int getBatteryPercentage() {
return batteryPercentage;
}
public void setBatteryPercentage(int batteryPercentage) {
this.batteryPercentage = batteryPercentage;
setChanged();
notifyObservers();
}
}
The view knows the Model:
public class View implements Observer {
private Model model;
private JTextField txtFldSpeed;
private JTextField txtFldBattery;
private JFrame mainWindow;
public View(Model m) {
this.model = m;
initialize();
}
private void initialize() {
mainWindow = new JFrame();
mainWindow.setTitle("New Window");
mainWindow.setMinimumSize(new Dimension(1280, 720));
mainWindow.setBounds(100, 100, 1280, 720);
mainWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel tPanel1 = new JPanel();
tPanel1.setBorder(new LineBorder(new Color(0, 0, 0)));
tPanel1.setLayout(null);
mainWindow.getContentPane().add(tPanel1);
mainWindow.getContentPane().add(tPanel1);
txtFldSpeed = new JTextField();
txtFldSpeed.setEditable(false);
txtFldSpeed.setBounds(182, 11, 116, 22);
tPanel1.add(txtFldSpeed);
txtFldBattery = new JTextField();
txtFldBattery.setEditable(false);
txtFldBattery.setBounds(182, 43, 116, 22);
tPanel1.add(txtFldBattery);
mainWindow.setVisible(true);
}
#Override
public void update(Observable o, Object arg) {
txtFldSpeed.setText(Float.toString(model.getSpeed()) + " kn");
txtFldBattery.setText(Integer.toString(model.getBatteryPercentage()) + " %");
}
}
The Controller adds the View as a Observer of the Model:
public class Controller {
private Model model;
private View view;
public Controller(Model m, View v) {
this.model = m;
this.view = v;
}
public void initController() {
model.addObserver(view);
model.setSpeed(10);
}
}
What I am expecting is something that, when the Model is updated, let's say, function setSpeed() is called, the View is told that she needs to update itself on that specific field and not every "changable" field (like the txtFldBattery.
I want to do this because on the View, there are fields being updated a couple of times per second, and because I need to update everything on the view, a JComboBox which doesn't need to update that often, keeps closing when trying to select a option.
I would use SwingPropertyChangeSupport, make each of the model's state fields a "bound property" so that each state field can be listened to separately.
For instance, say you have a model that looked like this:
public class MvcModel {
public static final String SPEED = "speed";
public static final String BATTERY = "battery";
public static final int MAX_SPEED = 40;
private float speed;
private int batteryPercentage;
private SwingPropertyChangeSupport pcSupport = new SwingPropertyChangeSupport(this);
public float getSpeed() {
return speed;
}
public void setSpeed(float speed) {
float oldValue = this.speed;
float newValue = speed;
this.speed = speed;
pcSupport.firePropertyChange(SPEED, oldValue, newValue);
}
public int getBatteryPercentage() {
return batteryPercentage;
}
public void setBatteryPercentage(int batteryPercentage) {
int oldValue = this.batteryPercentage;
int newValue = batteryPercentage;
this.batteryPercentage = batteryPercentage;
pcSupport.firePropertyChange(BATTERY, oldValue, newValue);
}
public void addPropertyChangeListener(PropertyChangeListener listener) {
pcSupport.addPropertyChangeListener(listener);
}
public void removePropertyChangeListener(PropertyChangeListener listener) {
pcSupport.removePropertyChangeListener(listener);
}
public void addPropertyChangeListener(String name, PropertyChangeListener listener) {
pcSupport.addPropertyChangeListener(name, listener);
}
public void removePropertyChangeListener(String name, PropertyChangeListener listener) {
pcSupport.removePropertyChangeListener(name, listener);
}
}
Both the speed and the batteryPercent fields are "bound fields" in that any changes to these fields will trigger the property change support object to fire a notification message to any listeners that have registered with the support object, as reflected in the public void setXxxx(...) methods.
This way the controller could register listeners on the model for whatever properties it wants to listen to, and then notify the view of any changes. For example:
class SpeedListener implements PropertyChangeListener {
#Override
public void propertyChange(PropertyChangeEvent evt) {
float speed = model.getSpeed();
view.setSpeed(speed);
}
}
The set up could look something like:
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.GridLayout;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import javax.swing.*;
import javax.swing.event.SwingPropertyChangeSupport;
public class MVC2 {
private static void createAndShowGui() {
MvcModel model = new MvcModel();
MvcView view = new MvcView();
MvcController controller = new MvcController(model, view);
controller.init();
JFrame frame = new JFrame("MVC2");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(view.getMainDisplay());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> createAndShowGui());
}
}
class MvcView {
private JPanel mainPanel = new JPanel();
private JSlider speedSlider = new JSlider(0, MvcModel.MAX_SPEED);
private JSlider batterySlider = new JSlider(0, 100);
private JProgressBar speedBar = new JProgressBar(0, MvcModel.MAX_SPEED);
private JProgressBar batteryPercentBar = new JProgressBar(0, 100);
public MvcView() {
speedSlider.setMajorTickSpacing(5);
speedSlider.setMinorTickSpacing(1);
speedSlider.setPaintTicks(true);
speedSlider.setPaintLabels(true);
speedSlider.setPaintTrack(true);
batterySlider.setMajorTickSpacing(20);
batterySlider.setMinorTickSpacing(5);
batterySlider.setPaintTicks(true);
batterySlider.setPaintLabels(true);
batterySlider.setPaintTrack(true);
speedBar.setStringPainted(true);
batteryPercentBar.setStringPainted(true);
JPanel inputPanel = new JPanel(new GridLayout(0, 1));
inputPanel.add(createTitledPanel("Speed", speedSlider));
inputPanel.add(createTitledPanel("Battery %", batterySlider));
JPanel displayPanel = new JPanel(new GridLayout(0, 1));
displayPanel.add(createTitledPanel("Speed", speedBar));
displayPanel.add(createTitledPanel("Battery %", batteryPercentBar));
mainPanel.setLayout(new GridLayout(1, 0));
mainPanel.add(createTitledPanel("Input", inputPanel));
mainPanel.add(createTitledPanel("Display", displayPanel));
}
private JComponent createTitledPanel(String title, JComponent component) {
JPanel titledPanel = new JPanel(new BorderLayout());
titledPanel.setBorder(BorderFactory.createTitledBorder(title));
titledPanel.add(component);
return titledPanel;
}
public JComponent getMainDisplay() {
return mainPanel;
}
public void setSpeed(float speed) {
speedBar.setValue((int) speed);
}
public void setBatteryPercent(int batteryPercent) {
batteryPercentBar.setValue(batteryPercent);
}
public JSlider getSpeedSlider() {
return speedSlider;
}
public JSlider getBatterySlider() {
return batterySlider;
}
}
class MvcController {
private MvcModel model;
private MvcView view;
public MvcController(MvcModel model, MvcView view) {
this.model = model;
this.view = view;
model.addPropertyChangeListener(MvcModel.BATTERY, new BatteryListener());
model.addPropertyChangeListener(MvcModel.SPEED, new SpeedListener());
view.getSpeedSlider().addChangeListener(chngEvent -> {
int value = view.getSpeedSlider().getValue();
model.setSpeed(value);
});
view.getBatterySlider().addChangeListener(chngEvent -> {
int value = view.getBatterySlider().getValue();
model.setBatteryPercentage(value);
});
}
public void init() {
view.getSpeedSlider().setValue(10);
view.getBatterySlider().setValue(100);
model.setSpeed(10);
model.setBatteryPercentage(100);
}
class SpeedListener implements PropertyChangeListener {
#Override
public void propertyChange(PropertyChangeEvent evt) {
float speed = model.getSpeed();
view.setSpeed(speed);
}
}
class BatteryListener implements PropertyChangeListener {
#Override
public void propertyChange(PropertyChangeEvent evt) {
int batteryPercent = model.getBatteryPercentage();
view.setBatteryPercent(batteryPercent);
}
}
}
Side note: Observer and Observable have been deprecated in the most recent version of Java and so should their use should probably be avoided.
In your update method implementation you can determine with first argument o which Observable has changed and with second argument arg which value changed when you call: notifyObservers(this.speed);
Note that notifyObservers's signature accepts Object, and float primitive is not a subclass of Object.

Magic movement in game tile by tile

I have a 2D tile game and my hero can use magic(in this case fire), and the goal is to make the fireball move tile by tile until it finds either a wall or an enemy and to make the game stop while the fire is moving. I already have the fire moving and stopping if there is a wall or an enemy(and damaging the enemy). The problem is i can't seem to make the game show the fireball change from tile to tile, which means when i launch the fireball the game automatically shows me the fireball in its last position before collision, and then it disappears from the tiles. Anyone got any ideas as to what I am doing wrong or what i should do to make the game update the fire tile by tile?
(Btw i thought it might have something to do with my observer but I've tried thread.sleep and wait() and it isn't quite working, maybe I am doing it the wrong way).Thank you for your help and if you guys need any code just ask.
public class ImageMatrixGUI extends Observable {
private static final ImageMatrixGUI INSTANCE = new ImageMatrixGUI();
private final String IMAGE_DIR = "images";
private final int SQUARE_SIZE;
private final int N_SQUARES_WIDTH;
private final int N_SQUARES_HEIGHT;
private JFrame frame;
private JPanel panel;
private JPanel info;
private Map<String, ImageIcon> imageDB = new HashMap<String, ImageIcon>();
private List<ImageTile> images = new ArrayList<ImageTile>();
private List<ImageTile> statusImages = new ArrayList<ImageTile>();
private int lastKeyPressed;
private boolean keyPressed;
private ImageMatrixGUI() {
SQUARE_SIZE = 48;
N_SQUARES_WIDTH = 10;
N_SQUARES_HEIGHT = 10;
init();
}
public static ImageMatrixGUI getInstance() {
return INSTANCE;
}
public void setName(final String name) {
frame.setTitle(name);
}
private void init() {
frame = new JFrame();
panel = new RogueWindow();
info = new InfoWindow();
panel.setPreferredSize(new Dimension(N_SQUARES_WIDTH * SQUARE_SIZE, N_SQUARES_HEIGHT * SQUARE_SIZE));
info.setPreferredSize(new Dimension(N_SQUARES_WIDTH * SQUARE_SIZE, SQUARE_SIZE));
info.setBackground(Color.BLACK);
frame.add(panel);
frame.add(info, BorderLayout.NORTH);
frame.pack();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
initImages();
new KeyWatcher().start();
frame.addKeyListener(new KeyListener() {
#Override
public void keyTyped(KeyEvent e) {
}
#Override
public void keyReleased(KeyEvent e) {
}
#Override
public void keyPressed(KeyEvent e) {
lastKeyPressed = e.getKeyCode();
keyPressed = true;
releaseObserver();
}
});
}
synchronized void releaseObserver() {
notify();
}
synchronized void waitForKey() throws InterruptedException {
while (!keyPressed) {
wait();
}
setChanged();
notifyObservers(lastKeyPressed);
keyPressed = false;
}
private void initImages() {
File dir = new File(IMAGE_DIR);
for (File f : dir.listFiles()) {
assert (f.getName().lastIndexOf('.') != -1);
imageDB.put(f.getName().substring(0, f.getName().lastIndexOf('.')),
new ImageIcon(IMAGE_DIR + "/" + f.getName()));
}
}
public void go() {
frame.setVisible(true);
}
public void newImages(final List<ImageTile> newImages) {
synchronized (images) { // Added 16-Mar-2016
if (newImages == null)
return;
if (newImages.size() == 0)
return;
for (ImageTile i : newImages) {
if (!imageDB.containsKey(i.getName())) {
throw new IllegalArgumentException("No such image in DB " + i.getName());
}
}
images.addAll(newImages);
}
}
public void removeImage(final ImageTile image) {
synchronized (images) {
images.remove(image);
}
}
public void addImage(final ImageTile image) {
synchronized (images) {
images.add(image);
}
}
public void clearImages() {
synchronized (images) {
images.clear();
}
public void newStatusImages(final List<ImageTile> newImages) {
synchronized (statusImages) {
if (newImages == null)
return;
if (newImages.size() == 0)
return;
for (ImageTile i : newImages) {
if (!imageDB.containsKey(i.getName())) {
throw new IllegalArgumentException("No such image in DB " + i.getName());
}
}
statusImages.addAll(newImages);
}
}
public void removeStatusImage(final ImageTile image) {
synchronized (statusImages) {
statusImages.remove(image);
}
public void addStatusImage(final ImageTile image) {
synchronized (statusImages) {
statusImages.add(image);
}
}
public void clearStatus() {
synchronized (statusImages) {
statusImages.clear();
}
}
#SuppressWarnings("serial")
private class RogueWindow extends JPanel {
#Override
public void paintComponent(Graphics g) {
// System.out.println("Thread " + Thread.currentThread() + "
// repainting");
synchronized (images) {
for (ImageTile i : images) {
g.drawImage(imageDB.get(i.getName()).getImage(), i.getPosition().getX() * SQUARE_SIZE,
i.getPosition().getY() * SQUARE_SIZE, SQUARE_SIZE, SQUARE_SIZE, frame);
}
}
}
}
#SuppressWarnings("serial")
private class InfoWindow extends JPanel {
#Override
public void paintComponent(Graphics g) {
synchronized (statusImages) {
for (ImageTile i : statusImages)
g.drawImage(imageDB.get(i.getName()).getImage(), i.getPosition().getX() * SQUARE_SIZE, 0,
SQUARE_SIZE, SQUARE_SIZE, frame);
}
}
}
private class KeyWatcher extends Thread {
public void run() {
try {
while (true)
waitForKey();
} catch (InterruptedException e) {
}
}
}
public void update() {
frame.repaint();
}
public void dispose() {
images.clear();
statusImages.clear();
imageDB.clear();
frame.dispose();
}
public Dimension getGridDimension() {
return new Dimension(N_SQUARES_WIDTH, N_SQUARES_HEIGHT);
}
}

Expanding one field while others are collapsed in blackberry java

I am developing an app in which i am adding and deleting fields based on setting flag to true or false.but what i am trying to do is if i click on field that particular field should expand while others are collapsed(even if it is expanded)
i googled it but i didnt get solution please help me i am new to blackberry java
i have used below code
public final class MyScreen extends MainScreen implements
FieldChangeListener
{
/**
* Creates a new MyScreen object
*/
private VerticalFieldManager main_manager;
private HorizontalFieldManager parentNodes;
private LabelField parent_lables[];
private Bitmap bitmap,upbitmap;
private BitmapField bitmap_field[];
private VerticalFieldManager submanager[];
private int sizeOfParentNodes=3;
private int sizeOfChildNodes=5;
private static boolean flag[];
public MyScreen()
{
// Set the displayed title of the screen
bitmap=Bitmap.getBitmapResource("arrow.png");
upbitmap=Bitmap.getBitmapResource("uparrow.png");
main_manager=new
VerticalFieldManager(Manager.VERTICAL_SCROLL|VERTICAL_SCROLLBAR){
protected void sublayout(int maxWidth, int maxHeight) {
super.sublayout(Display.getWidth(), Display.getHeight());
setExtent(Display.getWidth(), Display.getHeight());
};
};
parent_lables=new LabelField[sizeOfParentNodes];
flag=new boolean[sizeOfParentNodes];
submanager=new VerticalFieldManager[sizeOfParentNodes];
bitmap_field=new BitmapField[sizeOfParentNodes];
for(int i=0;i<sizeOfParentNodes;i++)
{
submanager[i]=new VerticalFieldManager();
updateGUI(i);
main_manager.add(submanager[i]);
}
add(main_manager);
}
public void fieldChanged(Field field, int context) {
// TODO Auto-generated method stub
synchronized (UiApplication.getEventLock()) {
for(int i=0;i<sizeOfParentNodes;i++)
{ if(field==parent_lables[i])
{
if(flag[i]==true){
flag[i]=false;
submanager[i].deleteAll();
updateGUI(i);
parent_lables[i].setFocus();
}else{
flag[i]=true;
bitmap_field[i].setBitmap(upbitmap);
submanager[i].invalidate();
}
}
}
}
}
public void updateGUI(int index)
{
parentNodes=new HorizontalFieldManager(USE_ALL_WIDTH);
bitmap_field[index]=new BitmapField(bitmap);
parentNodes.add(bitmap_field[index]);
parent_lables[index]=new LabelField("Day"+index,Field.FOCUSABLE){
protected boolean navigationClick(int status, int time) {
fieldChangeNotify(1);
return true;
};
};
parentNodes.add(parent_lables[index]);
parent_lables[index].setChangeListener(this);
submanager[index].add(parentNodes);
}
}
I knocked this together, and will likely need some tweaks by you to get it exactly how you want it, but it should be something you can work from. Assuming I've understood your question correctly.
You'll need to create a base field, a helper able to manage a list of them, and a callback. The fact that you need a base field is the biggest downfall, because it immediately excludes all other widgets you have, as they need to be made from scratch with the paint method. You can use a VerticalFieldManager instead of field by extending VerticalFieldManager instead of Field.
On to the java classes.
My CollapsableField.java looks as follows:
public abstract class CollapsableField extends Field
{
// We make use of a different listener than the FieldChangeListener, since you can only attach one and we will most likely want to do so, we can't "occupy" the listener.
private CollapseListener listener;
private boolean collapsed;
protected int collapsedWidth;
protected int collapsedHeight;
public CollapsableField()
{
collapsed = true;
// Field is completely collapsed by default
collapsedWidth = 0;
collapsedHeight = 0;
}
public void setCollapseListener(CollapseListener listener)
{
this.listener = listener;
}
public final boolean isCollapsed()
{
return collapsed;
}
public final void collapse()
{
this.collapsed = true;
if (listener != null)
{
listener.onCollapse(this);
}
fieldChangeNotify(0); // Notify that the field has changed, so that attached field change listeners will fire
updateLayout(); // re-call layout
}
public final void expand()
{
this.collapsed = false;
if (listener != null)
{
listener.onExpand(this);
}
fieldChangeNotify(0); // Notify that the field has changed, so that attached field change listeners will fire
updateLayout(); // re-call layout
}
protected void layout(int width, int height)
{
if (collapsed)
{
// Set dimensions to collapsed
setExtent(collapsedWidth, collapsedHeight);
}
else
{
// Set dimensions to what the extending class specified
setExtent(width, height);
}
}
protected final void paint(Graphics graphics)
{
if (collapsed)
{
paintCollapsed(graphics);
}
else
{
paintExpanded(graphics);
}
}
protected abstract void paintCollapsed(Graphics graphics);
protected abstract void paintExpanded(Graphics graphics);
}
The Group then takes a list of these, applies a listener to each field as it's added. When a field signals that it has expanded, the group will tell all other fields to collapse themselves.
CollapsableGroup.java:
public class CollapsableGroup
{
private Vector fields;
private CollapseListener listener;
public CollapsableGroup()
{
fields = new Vector();
listener = new CollapseListener()
{
public void onExpand(CollapsableField source)
{
for (int i = 0; i < fields.size(); i++)
{
CollapsableField field = (CollapsableField) fields.elementAt(i);
if ((!field.isCollapsed()) && (field != source))
{
field.collapse();
}
}
}
public void onCollapse(CollapsableField source)
{
// Don't need to handle this. Method is here just for completeness
}
};
}
public void add(CollapsableField field)
{
field.setCollapseListener(listener);
fields.addElement(field);
}
public void remove(CollapsableField field)
{
field.setCollapseListener(null);
fields.removeElement(field);
}
/**
* Returns the currently expanded field. Returns <b>null</b> if all fields are collapsed.
*
* #return
*/
public CollapsableField getExpandedField()
{
for (int i = 0; i < fields.size(); i++)
{
CollapsableField field = (CollapsableField) fields.elementAt(i);
if (!field.isCollapsed())
{
return field;
}
}
return null;
}
public void expand(CollapsableField field)
{
field.expand(); // Listeners should take care of the rest
}
public void collapseAll()
{
for (int i = 0; i < fields.size(); i++)
{
CollapsableField field = (CollapsableField) fields.elementAt(i);
if (!field.isCollapsed())
{
field.collapse();
}
}
}
}
And finally the listener interface.
CollapseListener.java:
interface CollapseListener
{
public void onExpand(CollapsableField source);
public void onCollapse(CollapsableField source);
}
Those three classes should be all that you need. The classes that follow are my example/test classes.
TestLabel.java is an example of an extended class:
public class TestLabel extends CollapsableField
{
private String text;
private String collapsedText;
public TestLabel(String text, String collapsedText)
{
this.text = text;
this.collapsedText = collapsedText;
// Tells the layout method to collapse to the size of this text
collapsedWidth = getFont().getAdvance(collapsedText);
collapsedHeight = getFont().getHeight();
}
public int getPreferredWidth()
{
return getFont().getAdvance(text);
}
public int getPreferredHeight()
{
return getFont().getHeight();
}
protected void layout(int width, int height)
{
super.layout(getPreferredWidth(), getPreferredHeight());
}
protected void paintCollapsed(Graphics graphics)
{
// Paints only the collapsedText
graphics.drawText(collapsedText, 0, 0);
}
protected void paintExpanded(Graphics graphics)
{
// Paints the full Text
graphics.drawText(text, 0, 0);
}
protected boolean touchEvent(TouchEvent message)
{
// Toggle on mouse press
if (message.getEvent() == TouchEvent.CLICK)
{
if (isCollapsed())
{
expand();
}
else
{
collapse();
}
return true;
}
return super.touchEvent(message);
}
}
The following screen contains some of the fields to show that both the widgets themselves and the group can manipulate the fields.
MyScreen.java:
public final class MyScreen extends MainScreen
{
public MyScreen()
{
// Set the displayed title of the screen
setTitle("MyTitle");
final CollapsableGroup group = new CollapsableGroup();
final TestLabel label1 = new TestLabel("Label1", "L1");
label1.setBackground(BackgroundFactory.createSolidBackground(0x999999));
group.add(label1);
final TestLabel label2 = new TestLabel("Label2", "L2");
label2.setBackground(BackgroundFactory.createSolidBackground(0xBBBBBB));
group.add(label2);
final TestLabel label3 = new TestLabel("Label3", "L3");
label3.setBackground(BackgroundFactory.createSolidBackground(0xDDDDDD));
group.add(label3);
ButtonField collapseAll = new ButtonField("Collapse All")
{
protected boolean navigationClick(int status, int time)
{
group.collapseAll();
return true;
}
};
add(collapseAll);
ButtonField expand1 = new ButtonField("Expand1")
{
protected boolean navigationClick(int status, int time)
{
group.expand(label1);
return true;
}
};
add(expand1);
ButtonField expand2 = new ButtonField("Expand2")
{
protected boolean navigationClick(int status, int time)
{
group.expand(label2);
return true;
}
};
add(expand2);
ButtonField expand3 = new ButtonField("Expand3")
{
protected boolean navigationClick(int status, int time)
{
group.expand(label3);
return true;
}
};
add(expand3);
add(label1);
add(label2);
add(label3);
}
}

Is MVC in Swing Thread Safe

I'm trying to touch limits of MVC architecture in Swing, but as I tried everything all (from SwingWorker or Runnable#Thread) are done on EDT
my questions:
is there some limits or strictly depends by order of the implementations
(wrapped into SwingWorker or Runnable#Thread) ?
limited is if is JComponent#method Thread Safe or not ?
essential characteristic of an MVC architecture in Swing, ?
inc. Container Re-Layout ?
note: for my SSCCE I take one of great examples by HFOE, and maybe by holding this principes strictly isn't possible to create any EDT lack or GUI freeze
import java.awt.BorderLayout;
import java.awt.event.*;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.util.LinkedList;
import java.util.Queue;
import javax.swing.*;
public class MVC_ProgressBarThread {
private MVC_ProgressBarThread() {
MVC_View view = new MVC_View();
MVC_Model model = new MVC_Model();
MVC_Control control = new MVC_Control(view, model);
view.setControl(control);
JFrame frame = new JFrame("MVC_ProgressBarThread");
frame.getContentPane().add(view);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
MVC_ProgressBarThread mVC_ProgressBarThread = new MVC_ProgressBarThread();
}
});
}
}
class MVC_View extends JPanel {
private static final long serialVersionUID = 1L;
private MVC_Control control;
private JProgressBar progressBar = new JProgressBar();
private JButton startActionButton = new JButton("Press Me and Run this Madness");
private JLabel myLabel = new JLabel("Nothing Special");
public MVC_View() {
startActionButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
buttonActionPerformed();
}
});
JPanel buttonPanel = new JPanel();
startActionButton.setFocusPainted(false);
buttonPanel.add(startActionButton);
setLayout(new BorderLayout(10, 10));
add(buttonPanel, BorderLayout.NORTH);
progressBar.setStringPainted(true);
add(progressBar, BorderLayout.CENTER);
myLabel.setIcon(UIManager.getIcon("OptionPane.questionIcon"));
myLabel.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
add(myLabel, BorderLayout.SOUTH);
}
public void setControl(MVC_Control control) {
this.control = control;
}
private void buttonActionPerformed() {
if (control != null) {
control.doButtonAction();
}
}
public void setProgress(int progress) {
progressBar.setValue(progress);
}
public void setProgressLabel(String label) {
progressBar.setString(label);
}
public void setIconLabel(Icon icon) {
myLabel.setIcon(icon);
}
public void start() {
startActionButton.setEnabled(false);
}
public void done() {
startActionButton.setEnabled(true);
setProgress(100);
setProgressLabel(" Done !!! ");
setIconLabel(null);
}
}
class MVC_Control {
private MVC_View view;
private MVC_Model model;
public MVC_Control(final MVC_View view, final MVC_Model model) {
this.view = view;
this.model = model;
model.addPropertyChangeListener(new PropertyChangeListener() {
#Override
public void propertyChange(PropertyChangeEvent pce) {
if (MVC_Model.PROGRESS.equals(pce.getPropertyName())) {
view.setProgress((Integer) pce.getNewValue());
}
if (MVC_Model.PROGRESS1.equals(pce.getPropertyName())) {
view.setProgressLabel((String) pce.getNewValue());
}
if (MVC_Model.PROGRESS2.equals(pce.getPropertyName())) {
view.setIconLabel((Icon) pce.getNewValue());
}
}
});
}
public void doButtonAction() {
view.start();
SwingWorker<Void, Void> swingworker = new SwingWorker<Void, Void>() {
#Override
protected Void doInBackground() throws Exception {
model.reset();
model.startSearch();
return null;
}
#Override
protected void done() {
view.done();
}
};
swingworker.execute();
}
}
class MVC_Model {
public static final String PROGRESS = "progress";
public static final String PROGRESS1 = "progress1";
public static final String PROGRESS2 = "progress2";
private static final int MAX = 11;
private static final long SLEEP_DELAY = 1000;
private int progress = 0;
private String label = "Start";
private PropertyChangeSupport pcs = new PropertyChangeSupport(this);
private PropertyChangeSupport pcs1 = new PropertyChangeSupport(this);
private PropertyChangeSupport pcs2 = new PropertyChangeSupport(this);
private final String[] petStrings = {"Bird", "Cat", "Dog",
"Rabbit", "Pig", "Fish", "Horse", "Cow", "Bee", "Skunk"};
private int index = 1;
private Queue<Icon> iconQueue = new LinkedList<Icon>();
private Icon icon = (UIManager.getIcon("OptionPane.questionIcon"));
public void setProgress(int progress) {
int oldProgress = this.progress;
this.progress = progress;
PropertyChangeEvent evt = new PropertyChangeEvent(this, PROGRESS,
oldProgress, progress);
pcs.firePropertyChange(evt);
}
public void setProgressLabel(String label) {
String oldString = this.label;
this.label = label;
PropertyChangeEvent evt = new PropertyChangeEvent(this, PROGRESS1,
oldString, label);
pcs1.firePropertyChange(evt);
}
public void setIconLabel(Icon icon) {
Icon oldIcon = this.icon;
this.icon = icon;
PropertyChangeEvent evt = new PropertyChangeEvent(this, PROGRESS2,
oldIcon, icon);
pcs2.firePropertyChange(evt);
}
public void reset() {
setProgress(0);
}
public void addPropertyChangeListener(PropertyChangeListener listener) {
pcs.addPropertyChangeListener(listener);
pcs1.addPropertyChangeListener(listener);
pcs2.addPropertyChangeListener(listener);
}
public void startSearch() {
iconQueue.add(UIManager.getIcon("OptionPane.errorIcon"));
iconQueue.add(UIManager.getIcon("OptionPane.informationIcon"));
iconQueue.add(UIManager.getIcon("OptionPane.warningIcon"));
iconQueue.add(UIManager.getIcon("OptionPane.questionIcon"));
for (int i = 0; i < MAX; i++) {
int newValue = (100 * i) / MAX;
setProgress(newValue);
setProgressLabel(petStrings[index]);
index = (index + 1) % petStrings.length;
setIconLabel(nextIcon());
try {
Thread.sleep(SLEEP_DELAY);
} catch (InterruptedException e) {
}
}
}
private Icon nextIcon() {
Icon icon1 = iconQueue.peek();
iconQueue.add(iconQueue.remove());
return icon1;
}
}
This is too long for a comment...
First and this is unrelated to the rest of this answer: there are many different MVCs out there and the one you used in that piece of code you posted here is not the same as the one used in the article you linked to: http://www.oracle.com/technetwork/articles/javase/mvc-136693.html
The article correctly points out that it's just "A common MVC implementation" (one where the view registers a listener listening to model changes). Your implementation is a different type of MVC, where the controller registers a listener listening to model changes and then updates the view.
Not that there's anything wrong with that: there are a lot of different types of MVCs out there (*).
(Another little caveat... Your view is aware of your controller in your example, which is a bit weird: there are other ways to do what you're doing without needing to "feed" the controller to the view like you do with your setControl(...) inside your MVCView.)
But anyway... You're basically nearly always modifying the GUI from outside the EDT (which you shouldn't be doing):
public void setIconLabel(final Icon icon) {
myLabel.setIcon(icon);
}
You can check it by adding this:
System.out.println("Are we on the EDT? " + SwingUtilities.isEventDispatchThread());
This is because you're eventually doing these updates from your SwingWorker thread (the SwingWorker thread is run outside the EDT: it's basically the point of a Swing worker).
I'd rather update the GUI from the EDT, doing something like this:
public void setIconLabel(final Icon icon) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
myLabel.setIcon(icon);
}
});
}

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