Develop Reference

JavaFX How do you bind an animation to a certain value?

I have made an application with JavaFX, where you have a picture with animated stuff in it, based on certain values in the app. The only problem I have: I don't really know, how to bind the values to the animations, so the animations move, based on the value put in. For example: if the value is 10, the animation should move fast. If the value is 1 the animation should move slow. Here is the code for the animation (it is smoke, coming out of a house):
smoke = new Image(HydroControl.class.getResource("/imgs/smoke.png").toExternalForm());
smokeView = new ImageView(smoke);
smokeView.setX(-190);
smokeView.setY(60);
Path path3 = new Path();
path3.getElements().add(new MoveTo(1,-60));
path3.getElements().add(new CubicCurveTo(0, 0, 0, 0, 0, 0));
PathTransition pathTransition3 = new PathTransition();
pathTransition3.setDuration(Duration.millis(2000));
pathTransition3.setPath(path3);
pathTransition3.setNode(smokeView);
pathTransition3.setCycleCount(Timeline.INDEFINITE);
pathTransition3.setAutoReverse(true);
pathTransition3.play();
Here is the code with the values:
public class PresentationModel {
private final DoubleProperty waterValue = new SimpleDoubleProperty();
private final DoubleProperty powerValue = new SimpleDoubleProperty();
private final BooleanProperty isOnValue = new SimpleBooleanProperty();
public double getWaterValue() {
return waterValue.get();
}
public DoubleProperty waterValueProperty() {
return waterValue;
}
public void setWaterValue(double waterValue) {
this.waterValue.set(waterValue);
}
public double getPowerValue() {
return powerValue.get();
}
public DoubleProperty powerValueProperty() {
return powerValue;
}
public void setPowerValue(double powerValue) {
this.powerValue.set(powerValue);
}
public boolean isIsOnValue() {
return isOnValue.get();
}
public BooleanProperty isOnValueProperty() {
return isOnValue;
}
public void setIsOnValue(boolean isOnValue) {
this.isOnValue.set(isOnValue);
}
}
I would be really glad if you could help me. Thank you.

Bind the properties of your transition to the values of your model with a calculation from the Bindings class. For example:
pathTransition3.durationProperty().bind(Bindings.multiply(Bindings.multiply(model.powerProperty(), model.waterValueProperty()), 500d));
model.isOnValueProperty().addListener((v, o, n) -> {
if (n) {
pathTransition3.play();
} else {
pathTransition3.pause();
}
});

AndEngine, PhysicsWorld not updating?

I'm not entirely sure what I'm doing wrong. I have written this code multiple times before without problems. The problem is that the physics world just does not seem to be updating and I don't know why! Right now I have a gameScene class which extends a normal scene, this is the onCreate method:
#Override
public void create() {
ParallaxBackground background = new ParallaxBackground(0, 0, 0);
background.attachParallaxEntity(new ParallaxEntity(0, new Sprite(0, 0, res.BasicBackground, res.vbom)));
this.setBackground(background);
test = new Sprite(0, 0, res.GrassRegion, res.vbom);
FixtureDef fix = PhysicsFactory.createFixtureDef(10f, 0f, 10f);
Body bod = PhysicsFactory.createBoxBody(physicsWorld, test, BodyType.DynamicBody, fix);
attachChild(test);
physicsWorld = new PhysicsWorld(new Vector2(SensorManager.GRAVITY_EARTH, SensorManager.GRAVITY_EARTH), false);
physicsWorld.registerPhysicsConnector(new PhysicsConnector(test, bod, true, true));
this.registerUpdateHandler(physicsWorld);
}
(I removed a lot of the unnecessary things) I just have a basic test sprite to make sure that the physics is working (which it is not). The app runs without any errors, its just that the sprite will not move, leading me to think that its a problem with the physics world being update.
As you can see, I'm setting the gravity to be accelerating in both the X and Y directions. I did this because I thought maybe it wasn't working in one direction for some reason. I'm thinking that maybe I have to set the scene to update in the main activity? But I don't remember having to do that with any of my other apps. Any help is appreciated thank you :)

No, this.registerUpdateHandler(physicsWorld); will do just fine. Try adding this:
physicsWorld = new PhysicsWorld(new Vector2(0, AHC.WORLD_GRAVITY), false) {
#Override
public void onUpdate(float pSecondsElapsed) {
super.onUpdate(pSecondsElapsed);
}
};
And put a breakpoint or Log.i(TAG, "hey"); inside onUpdate to check if it hits it
EDIT:
Try registering a "normal" UpdateHandler, you can do it in 2 ways:
public class YourGameActivity implements IUpdateHandler{
...
private void yourSetupMethod(){
registerUpdateHandler(this);
}
#Override
public void reset() {}
#Override
public void onUpdate(float pSecondsElapsed) {
Log.i(TAG, "hey");
}
}
or you can create a class that implements IUpdateHandler and then:
public class YourGameActivity{
private MyClassThatImplementsIUpdateHandler mInstance;
...
private void yourSetupMethod(){
registerUpdateHandler(mInstance);
}
}
It's the same.
Try it and see if it logs something, if for some reason you can't see the log use a breakpoint just to be sure.

How to create interactive graphic with Vaadin?

I want to develop a simple interactive game (like arcanoid). I already have implemented a menu and different views, and now I need to develop the actually game (draw flying ball, some movable platform) and I don't know how to do this. I need something like canvas where I can draw my graphic each frame.
I have tryed to implement this with Canvas and Timer. But it doesn't want update graphic itself, but only when user clicks on screen or similar. Also I saw com.google.gwt.canvas.client.Canvas, but I cannot understand how to use it in Vaadin application.
So my question is next: is it possible to draw some graphic each frame with high framerate in any way? If possible, how can I do this?
P.S. I use the Vaadin 7.3.3.

ADDED LATER:
Here is a link to my educational project with implementation below.
I'll be glad if it helps someone.
ORIGINAL ANSWER:
Well... I found the solution myself. First of all, I have created my own widget - "client side" component (according to this article).
Client side part:
public class GWTMyCanvasWidget extends Composite {
public static final String CLASSNAME = "mycomponent";
private static final int FRAMERATE = 30;
public GWTMyCanvasWidget() {
canvas = Canvas.createIfSupported();
initWidget(canvas);
setStyleName(CLASSNAME);
}
Connector:
#Connect(MyCanvas.class)
public class MyCanvasConnector extends AbstractComponentConnector {
#Override
public Widget getWidget() {
return (GWTMyCanvasWidget) super.getWidget();
}
#Override
protected Widget createWidget() {
return GWT.create(GWTMyCanvasWidget.class);
}
}
Server side part:
public class MyCanvas extends AbstractComponent {
#Override
public MyCanvasState getState() {
return (MyCanvasState) super.getState();
}
}
Then I just add MyCanvas component on my View:
private void createCanvas() {
MyCanvas canvas = new MyCanvas();
addComponent(canvas);
canvas.setSizeFull();
}
And now I can draw anything on Canvas (on client side in GWTMyCanvasWidget) with great performance =). Example:
public class GWTMyCanvasWidget extends Composite {
public static final String CLASSNAME = "mycomponent";
private static final int FRAMERATE = 30;
private Canvas canvas;
private Platform platform;
private int textX;
public GWTMyCanvasWidget() {
canvas = Canvas.createIfSupported();
canvas.addMouseMoveHandler(new MouseMoveHandler() {
#Override
public void onMouseMove(MouseMoveEvent event) {
if (platform != null) {
platform.setCenterX(event.getX());
}
}
});
initWidget(canvas);
Window.addResizeHandler(new ResizeHandler() {
#Override
public void onResize(ResizeEvent resizeEvent) {
resizeCanvas(resizeEvent.getWidth(), resizeEvent.getHeight());
}
});
initGameTimer();
resizeCanvas(Window.getClientWidth(), Window.getClientHeight());
setStyleName(CLASSNAME);
platform = createPlatform();
}
private void resizeCanvas(int width, int height) {
canvas.setWidth(width + "px");
canvas.setCoordinateSpaceWidth(width);
canvas.setHeight(height + "px");
canvas.setCoordinateSpaceHeight(height);
}
private void initGameTimer() {
Timer timer = new Timer() {
#Override
public void run() {
drawCanvas();
}
};
timer.scheduleRepeating(1000 / FRAMERATE);
}
private void drawCanvas() {
canvas.getContext2d().clearRect(0, 0, canvas.getCoordinateSpaceWidth(), canvas.getCoordinateSpaceHeight());
drawPlatform();
}
private Platform createPlatform() {
Platform platform = new Platform();
platform.setY(Window.getClientHeight());
return platform;
}
private void drawPlatform() {
canvas.getContext2d().fillRect(platform.getCenterX() - platform.getWidth() / 2, platform.getY() - 100, platform.getWidth(), platform.getHeight());
}
}

Update Android SurfaceView on-the-fly with new elements

I have a database filled with records in the following format: . What I want my application to do is select records from an external database, and display those records on the phone screen using a SurfaceView.
Currently, I have an Activity, and a Service responsible for the record-gathering portion of the application. The Activity passes an intent to the Service, and the Service responds by returning the records that need to be displayed. The records are stored in my program as instances of the Data class, and merely have the screen-coordinates of where the element should be drawn in the View (I am just drawing a circle for every record in the DB).
For the sake of brevity, I won't include the service but I will include a skeleton of the Activity class and the Data that I wish to display.
public class Data{
private int x;
private int y;
private int id;
private int shape;
/*
* Getters and setters for class properties
*/
}
public class Displayer extends Activity {
int ht;
int wt;
dataReceiver dreceiver;
public static Map<String, Data> Info;
private LinearLayout linear;
private static final int RADIUS = 20;
Panel panel;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
panel=new Panel(this);
setContentView(panel);
Intent scv = new Intent(this, DataService.class);
startService(scv);
}
/*
* Various other methods to take care of onDestroy, onPause, etc.
*/
public class dataReceiver extends BroadcastReceiver {
//Get new data from intents sent by the Service and store it in Info variable
//Update the Testing Map data-structure in the Panel SurfaceView with new records
panel.setData(Info);
}
}
The problem that I am having pertains to the SurfaceView. I realize that many people are going to suggest that I use just a regular View, but my application involves a lot of elements, so a SurfaceView would be much more suitable for my needs. Below is a skeleton of my SurfaceView class that contains a nested class to manage the threads.
public class Panel extends SurfaceView implements SurfaceHolder.Callback {
private PanelThread _thread;
private Paint circlepaint;
private Paint textpaint;
private static int CircleColor = Color.YELLOW;
private static int TextColor = Color.RED;
private static Map<String, Data> Testing;
public Panel(Context context, Map<String, Data> entries) {
super(context);
getHolder().addCallback(this);
_thread = new PanelThread(getHolder(), this);
setFocusable(true);
textpaint = new Paint(Paint.ANTI_ALIAS_FLAG);
textpaint.setStyle(Style.FILL_AND_STROKE);
textpaint.setColor(TextColor);
Testing = new HashMap<String, Data>();
// Log.d("TestingSize",String.valueOf(Testing.size()));
if (!(Testing.isEmpty())) {
Testing.clear();
}
for (Map.Entry<String, Data> e : entries.entrySet()) {
String keyvalue = e.getKey();
Data v = e.getValue();
Panel.Testing.put(keyvalue, v);
}
}
public Panel(Context context) {
super(context);
getHolder().addCallback(this);
_thread = new PanelThread(getHolder(), this);
setFocusable(true);
textpaint = new Paint(Paint.ANTI_ALIAS_FLAG);
textpaint.setStyle(Style.FILL_AND_STROKE);
textpaint.setColor(TextColor);
Testing = new HashMap<String, Victims>();
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
// TODO Auto-generated method stub
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
_thread.setRunning(true);
_thread.start();
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
/* we have to tell thread to shut down
* & wait for it to finish,
* or else it might touch the Surface
* after we return and explode
*/
boolean retry = true;
_thread.setRunning(false);
while (retry) {
try {
_thread.join();
retry = false;
} catch (InterruptedException e) {
// we will try it again and again...
}
}
}
/*If new records are received
* from the service, they can be updated
* using this method
*/
public void setData(Map<String,Data>Info){
Testing=Info;
}
/*
* Iterate over all contents of Testing List and display them to the screen
*/
#Override
public void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (!(Testing.isEmpty())) {
for (Map.Entry<String, Victims> e : Testing.entrySet()) {
Data d = e.getValue();
canvas.drawCircle(d.getX(), d.getY(), 10, circlepaint);
}
}
canvas.save();
canvas.restore();
}
/*
* Nested class to manage the threads for the SurfaceView
*/
class PanelThread extends Thread {
private SurfaceHolder _surfaceHolder;
private Panel _panel;
private boolean _run = false;
public PanelThread(SurfaceHolder surfaceHolder, Panel panel) {
_surfaceHolder = surfaceHolder;
_panel = panel;
}
public void setRunning(boolean run) {
_run = run;
}
public SurfaceHolder getSurfaceHolder() {
return _surfaceHolder;
}
#Override
public void run() {
Canvas c;
while (_run) {
c = null;
try {
c = _surfaceHolder.lockCanvas(null);
synchronized (_surfaceHolder) {
_panel.onDraw(c);
}
} finally {
// do this in a finally so that if an exception is thrown
// during the above, we don't leave the Surface in an
// inconsistent state
if (c != null) {
_surfaceHolder.unlockCanvasAndPost(c);
}
}
}
}
}//end of PanelThread
}//end of Panel
The problem that I'm having is that once I make the initial call to the Panel class, I'm going to be getting new records from the service, and consequently, my Info Map data-structure is going to get updated. However, my Panel class just gets stuck in a loop and never receives any new Data objects. All examples of SurfaceViews I've found have involved updating them methods within the SurfaceView class itself (e.g. touching the screen and creating a new image, etc.) Sadly, I'm stumped on this particular problem. Is there a better approach for designing my Activity/SurfaceView interaction? Is an additional View required?

From a quick look at your code I think the problem is that you are trying to update a data structure from the UI thread while acting on it in the PanelThread. It also looks like your Activity class and Panel are also out of sync - I don't see the setData method in your Panel class, but I assume it updates the Testing static member variable.
My suggestions:
1 - Testing should not be static - it's fundamentally associated with this instance of the class.
2 - Use Synchronize when touching the data (Testing). This should be done for both setting and reading the data.
3 - Put a sleep or a wait call in your run loop - this gives time for the activity UI thread to update Testing. Also saves battery and allows you to pick a frame rate for updates.

How to create blackberry screen slide animation similar to Blackberry App World?

does anyone knows how to use the blackberry JDE API to create a screen slide animation similar to Featured Items screen in the Blackberry App World? I am aware that in blackberry 5.0, there are some transition apis to perform that. But I am looking to do it for version 4.6 OS. It has the nice scrolling effect using the scrolling ball in blackberry bold.
Thanks.

As an alternative to the screenshot/Bitmap approach...
In the paint method of your screen you can use Graphics.pushContext(..) to push a clipping region and drawing offset. For best results, you'll want to do the transition in a runnable, and synchronize on the event lock. This will ensure that your screen can be dismissed in the middle of a transition.
Rough example:
class TransitionScreen extends Screen {
private int transitionOffset;
private boolean isTransitionHorizontal;
private ScreenTransition currentTransition;
public TransitionScreen(boolean isTransitionHorizontal) {
this.isTransitionHorizontal = isTransitionHorizontal;
transitionOffset = getTransitionMaximum(); // So the screen starts offset
}
protected void paint(Graphics graphics) {
// use transitionOffset as x or y depending on isTransitionHorizontal
graphics.pushContext(...);
}
protected void onExposed() {
transitionToOffset(0);
}
protected void onObscured() {
int target = getTransitionMaximum();
transitionToOffset(target);
}
private int getTransitionMaximum() {
return isTransitionHorizontal ? Display.getWidth() : Display.getHeight();
}
private void transitionToOffset(int target) {
if (currentTransition != null) {
currentTransition.stop();
}
currentTransition = new ScreenTransition(target);
getApplication().invokeLater(currentTransition);
}
}
class ScreenTransition implements Runnable {
private boolean animating;
private int target;
public ScreenTransitionUpdater(int target) {
this.target = target;
}
public void stop() {
animating = false;
}
public void run() {
while(animating) {
Object eventLock = getApplication().getEventLock();
synchronized(eventLock) {
// Interpolate myOffset to target
// Set animating = false if myOffset = target
invalidate();
}
}
}
}
No need to mark animating as volatile as it is ignored on this platform.

Maybe use a timer to change the coordinate position of the images in the paint method