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Intersect method not working, keeps returning true

My intersect method keeps returning true and setting my "score text" to intersect detected when my images do not collide, instead it changes the text as soon as the emulator starts. Please notify me if more code is needed and check back within 10 minutes. Thanks! -this is all my code and collision code starts at line 163, something is wrong with my collision code because collision isn't being detected, what should I do to fix my collision code.
here is my code:
public class MainActivity extends AppCompatActivity {
//Layout
private RelativeLayout myLayout = null;
//Screen Size
private int screenWidth;
private int screenHeight;
//Position
private float ballDownY;
private float ballDownX;
//Initialize Class
private Handler handler = new Handler();
private Timer timer = new Timer();
//Images
private ImageView net = null;
private ImageView ball = null;
//for net movement along x-axis
float x;
float y;
//points
private int points = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myLayout = (RelativeLayout) findViewById(R.id.myLayout);
//score
TextView score = (TextView) findViewById(R.id.score);
//imageviews
net = (ImageView) findViewById(R.id.net);
ball = (ImageView) findViewById(R.id.ball);
//retrieving screen size
WindowManager wm = getWindowManager();
Display disp = wm.getDefaultDisplay();
Point size = new Point();
disp.getSize(size);
screenWidth = size.x;
screenHeight = size.y;
//move to out of screen
ball.setX(-80.0f);
ball.setY(screenHeight + 80.0f);
//start timer
timer.schedule(new TimerTask() {
#Override
public void run() {
handler.post(new Runnable() {
#Override
public void run() {
changePos();
}
});
}
}, 0, 20);
}
public void changePos() {
//down
ballDownY += 10;
if (ball.getY() > screenHeight) {
ballDownX = (float) Math.floor((Math.random() * (screenWidth -
ball.getWidth())));
ballDownY = -100.0f;
}
ball.setY(ballDownY);
ball.setX(ballDownX);
/*INTERSECT METHOD
Rect rc1 = new Rect();
net.getDrawingRect(rc1);
Rect rc2 = new Rect();
ball.getDrawingRect(rc2);
if (Rect.intersects(rc1, rc2)) {
TextView score = (TextView) findViewById(R.id.score);
score.setText("INTERSECT DETECTED");
}*/
//make net follow finger
myLayout.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View view, MotionEvent event) {
MainActivity.this.x = event.getX();
y = event.getY();
if (event.getAction() == MotionEvent.ACTION_MOVE) {
net.setX(MainActivity.this.x);
net.setY(y);
}
return true;
}
});
}
public boolean Collision(ImageView net, ImageView ball)
{
Rect AR = new Rect();
net.getHitRect(AR);
Rect BR = new Rect();
ball.getHitRect(BR);
Render();
return AR.intersect(BR) || AR.contains(BR) || BR.contains(AR);
}
public void Render()
{
if(Collision(net, ball))
{
points++;
TextView score = (TextView)findViewById(R.id.score);
score.setText("Score:" + points);
}
}
}

I have reformed your code, try now
public class MainActivity extends AppCompatActivity
{
//Layout
private RelativeLayout myLayout = null;
//Screen Size
private int screenWidth;
private int screenHeight;
//Position
private float ballDownY;
private float ballDownX;
//Initialize Class
private Handler handler = new Handler();
private Timer timer = new Timer();
//Images
private ImageView net = null;
private ImageView ball = null;
//score
private TextView score = null;
//for net movement along x-axis
public float x = 0;
public float y = 0;
//points
private int points = 0;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
this.setContentView(R.layout.activity_main);
this.myLayout = (RelativeLayout) findViewById(R.id.myLayout);
this.score = (TextView) findViewById(R.id.score);
this.net = (ImageView) findViewById(R.id.net);
this.ball = (ImageView) findViewById(R.id.ball);
//retrieving screen size
WindowManager wm = getWindowManager();
Display disp = wm.getDefaultDisplay();
Point size = new Point();
disp.getSize(size);
screenWidth = size.x;
screenHeight = size.y;
//move to out of screen
this.ball.setX(-80.0f);
this.ball.setY(screenHeight + 80.0f);
//Error here
/*//Run constantly
new Handler().postDelayed(new Runnable()
{
#Override
public void run()
{
Render();
}
}, 100); //100 is miliseconds interval than sleep this process, 1000 miliseconds is 1 second*/
Thread t = new Thread() {
#Override
public void run() {
try {
while (!isInterrupted()) {
Thread.sleep(100);
runOnUiThread(new Runnable() {
#Override
public void run(){Render();}});}
}catch (InterruptedException e) {}}};
t.start();
}
public void Render()
{
changePos();
if(Collision(net, ball))
{
points++; //You dont need findView Textview score for that exists in OnCreate Method
this.score.setText("Score:" + points);
}
}
public void changePos()
{
//down
ballDownY += 10;
if (ball.getY() > screenHeight) {
ballDownX = (float) Math.floor((Math.random() * (screenWidth - ball.getWidth())));
ballDownY = -100.0f;
}
ball.setY(ballDownY);
ball.setX(ballDownX);
//make net follow finger
myLayout.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View view, MotionEvent event) {
x = event.getX();
y = event.getY();
if (event.getAction() == MotionEvent.ACTION_MOVE) {
net.setX(x);
net.setY(y);
}
return true;
}
});
public boolean Collision(ImageView net, ImageView ball)
{
Rect BallRect = new Rect();
ball.getHitRect(BallRect);
Rect NetRect = new Rect();
net.getHitRect(NetRect);
return BallRect.intersect(NetRect);
}
}

Something like this:
boolean collision = net.getRect().intersect(ball.getRect());
Collision is a boolean
if(boolean) //Action
Then
if(collision) score.setText("INTERSECT DETECTED");
OR
public boolean Collision(ImageView a, ImageView b)
{
Rect AR = new Rect();
a.getHitRect(myViewRect);
Rect BR = new Rect();
b.getHitRect(otherViewRect1);
return Rect.intersects(AR, BR);
}
--
if(Collision(net, ball))
{
//Do action
}
--
ImageView ball = (ImageView) findViewById(R.id.Ball);
ImageView net = (ImageView) findViewById(R.id.Net);
if(Collision(net, ball))
{
//Collision detected
}
--
import android.graphics.Rect;
public boolean Collision(ImageView ball, ImageView net)
{
Rect ballRect = new Rect();
ball.getDrawingRect(ballRect);
Rect netRect = new Rect();
net.getDrawingRect(netRect);
return Rect.intersects(ballRect, netRect);
}
Check this post how to detect when a ImageView is in collision with another ImageView?

Remove the last color form bitmap Undo

Please I need the help regarding Undo method , I tried to implement it like the code below but it is not remove the last color,
Kindly help me to resolve it.
awaiting your kind response.
Thanks in Advance.
MainActivity
public class MainActivity extends AppCompatActivity implements
View.OnTouchListener {
Button red, blue, yellow, undo;
Paint paint;
private RelativeLayout drawingLayout;
private MyView myView;
private ArrayList<Path> paths = new ArrayList<Path>();
private ArrayList<Path> undonePaths = new ArrayList<Path>();
/**
* Called when the activity is first created.
*/
/*
*
* private ImageView imageView; private Canvas cv; private Bitmap mask,
* original, colored; private int r,g,b; private int sG, sR, sB;
*/
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myView = new MyView(this);
drawingLayout = (RelativeLayout) findViewById(R.id.relative_layout);
drawingLayout.addView(myView);
red = (Button) findViewById(R.id.btn_red);
blue = (Button) findViewById(R.id.btn_blue);
yellow = (Button) findViewById(R.id.btn_yellow);
undo = (Button) findViewById(R.id.undo);
red.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
paint.setColor(Color.RED);
}
});
yellow.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
paint.setColor(Color.YELLOW);
}
});
blue.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
paint.setColor(Color.BLUE);
}
});
undo.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
myView.onClickUndo();
}
});
}
#Override
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
return false;
}
// flood fill
public class MyView extends View {
final Point p1 = new Point();
Bitmap mBitmap;
ProgressDialog pd;
Canvas canvas;
private Path path;
// Bitmap mutableBitmap ;
public MyView(Context context) {
super(context);
paint = new Paint();
paint.setAntiAlias(true);
pd = new ProgressDialog(context);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStrokeWidth(5f);
mBitmap = BitmapFactory.decodeResource(getResources(),
R.drawable.gp1_1).copy(Bitmap.Config.ARGB_8888, true);
this.path = new Path();
}
public void onClickUndo() {
if (paths.size() > 0) {
undonePaths.add(paths.remove(paths.size() - 1));
invalidate();
} else {
Toast.makeText(getContext(), getString(R.string.nomore), Toast.LENGTH_SHORT).show();
}
}
#Override
protected void onDraw(Canvas canvas) {
this.canvas = canvas;
paint.setColor(Color.GREEN);
// int width = drawingLayout.getWidth();
// int height = drawingLayout.getHeight();
// float centerX = (width - mBitmap.getWidth()) * 0.5f;
//float centerY = (height - mBitmap.getHeight()) * 0.5f;
canvas.drawBitmap(mBitmap, 0, 0, paint);
///////////////////////////////
for (Path p : paths) {
canvas.drawPath(p, paint);
//////////////////////////
}
}
#Override
public boolean onTouchEvent(MotionEvent event) {
float x = event.getX();
float y = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
p1.x = (int) x;
p1.y = (int) y;
final int sourceColor = mBitmap.getPixel((int) x, (int) y);
final int targetColor = paint.getColor();
new TheTask(mBitmap, p1, sourceColor, targetColor).execute();
paths.add(path);
invalidate();
}
return true;
}
public void clear() {
path.reset();
invalidate();
}
public int getCurrentPaintColor() {
return paint.getColor();
}
class TheTask extends AsyncTask<Void, Integer, Void> {
Bitmap bmp;
Point pt;
int replacementColor, targetColor;
public TheTask(Bitmap bm, Point p, int sc, int tc) {
this.bmp = bm;
this.pt = p;
this.replacementColor = tc;
this.targetColor = sc;
pd.setMessage(getString(R.string.wait));
pd.show();
}
#Override
protected void onPreExecute() {
pd.show();
}
#Override
protected void onProgressUpdate(Integer... values) {
}
#Override
protected Void doInBackground(Void... params) {
FloodFill f = new FloodFill();
f.floodFill(bmp, pt, targetColor, replacementColor);
return null;
}
#Override
protected void onPostExecute(Void result) {
pd.dismiss();
invalidate();
}
}
}
public class FloodFill {
public void floodFill(Bitmap image, Point node, int targetColor,
int replacementColor) {
int width = image.getWidth();
int height = image.getHeight();
int target = targetColor;
int replacement = replacementColor;
if (target != replacement) {
Queue<Point> queue = new LinkedList<Point>();
do {
int x = node.x;
int y = node.y;
while (x > 0 && image.getPixel(x - 1, y) == target) {
x--;
}
boolean spanUp = false;
boolean spanDown = false;
while (x < width && image.getPixel(x, y) == target) {
image.setPixel(x, y, replacement);
if (!spanUp && y > 0
&& image.getPixel(x, y - 1) == target) {
queue.add(new Point(x, y - 1));
spanUp = true;
} else if (spanUp && y > 0
&& image.getPixel(x, y - 1) != target) {
spanUp = false;
}
if (!spanDown && y < height - 1
&& image.getPixel(x, y + 1) == target) {
queue.add(new Point(x, y + 1));
spanDown = true;
} else if (spanDown && y < height - 1
&& image.getPixel(x, y + 1) != target) {
spanDown = false;
}
x++;
}
} while ((node = queue.poll()) != null);
}
}
}
}

I guess you mean the undo method doesn't work. The possible reason is the previous drawing on the canvas is not removed. Try clearing the canvas before drawing in the onDraw() method.
#Override protected void onDraw(Canvas canvas) {
this.canvas = canvas;
canvas. drawColor(0,PorterDuff.Mode.CLEAR); //This clears the canvas.
paint.setColor(Color.GREEN);
//rest of the code
}

Seems it is impossible to return previous color it is required an array for each point to store the used color in every point.

how to make a circle slowly "pop" onto the screen

Im making an app that displays multiple random circles on the screen. I want to know if i can expand the radius WHILE it is displaying the circle then disapeers. I have already written the code to randomly display the circles here it is.
public class SplashLaunch extends View{
Handler cool = new Handler();
DrawingView v;
ObjectAnimator aa = new ObjectAnimator();
Paint newPaint = new Paint();
int randomWidthOne = 0;
int randomHeightOne = 0;
private static int radiusOne = 300;
final int redColorOne = Color.RED;
final int greenColorOne = Color.GREEN;
private static int lastColorOne;
private final Random theRandom = new Random();
public SplashLaunch(Context context) {
super(context);
// TODO Auto-generated constructor stub
}
private final Runnable circleUpdater = new Runnable() {
#SuppressLint("NewApi")
#Override
public void run() {
lastColorOne = theRandom.nextInt(2) == 1 ? redColorOne : greenColorOne;
newPaint.setColor(lastColorOne);
cool.postDelayed(this, 500);
int x = 0;
while(x<=255){
newPaint.setAlpha(x);
x++;
}
invalidate();
}
};
#Override
protected void onAttachedToWindow(){
super.onAttachedToWindow();
cool.post(circleUpdater);
}
protected void onDetachedFromWindow(){
super.onDetachedFromWindow();
cool.removeCallbacks(circleUpdater);
}
#Override
protected void onDraw(Canvas canvas) {
// TODO Auto-generated method stub
super.onDraw(canvas);
if(theRandom == null){
randomWidthOne =(int) (theRandom.nextInt(Math.abs(getWidth()-radiusOne/2)) + radiusOne/2f);
randomHeightOne = (theRandom.nextInt((int)Math.abs((getHeight()-radiusOne/2 + radiusOne/2f))));
}else {
randomWidthOne =(int) (theRandom.nextInt(Math.abs(getWidth()-radiusOne/2)) + radiusOne/2f);
randomHeightOne = (theRandom.nextInt((int)Math.abs((getHeight()-radiusOne/2 + radiusOne/2f))));
}
canvas.drawCircle(randomWidthOne, randomHeightOne, radiusOne, newPaint);
}
}

I want to know if i can expand the radius WHILE it is displaying the circle then disappears
Yes you can. You simply animate the Scale of your view to a value greater than 1 to expand the view then back to 0 to make it "disappear".

I get a "cannot set a static reference error" how do i set the view to an xml file

So im trying to go to an XML file called "youfailed" and for some reason i am getting an error saying that it cannot get a static reference. Is there any way to do what im trying to do?
public class DrawingView extends View {
public DrawingView(Context context) {
super(context);
// TODO Auto-generated constructor stub
}
RectF rectf = new RectF(0, 0, 200, 0);
private static final int w = 100;
public static int lastColor = Color.BLACK;
private final Random random = new Random();
private final Paint paint = new Paint();
private final int radius = 230;
private final Handler handler = new Handler();
public static int redColor = Color.RED;
public static int greenColor = Color.GREEN;
int randomWidth = 0;
int randomHeight = 0;
public static int addPoints = 0;
private final Runnable updateCircle = new Runnable() {
#Override
public void run() {
lastColor = random.nextInt(2) == 1 ? redColor : greenColor;
paint.setColor(lastColor);
invalidate();
handler.postDelayed(this, 1000);
}
};
#Override
protected void onAttachedToWindow() {
super.onAttachedToWindow();
handler.post(updateCircle);
}
#Override
protected void onDetachedFromWindow() {
super.onDetachedFromWindow();
handler.removeCallbacks(updateCircle);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
// your other stuff here
if(random == null){
randomWidth =(int) (random.nextInt(Math.abs(getWidth()-radius/2)) + radius/2f);
randomHeight = (random.nextInt((int)Math.abs((getHeight()-radius/2 + radius/2f))));
}else {
randomWidth =(int) (random.nextInt(Math.abs(getWidth()-radius/2)) + radius/2f);
randomHeight = (random.nextInt((int)Math.abs((getHeight()-radius/2 + radius/2f))));
}
canvas.drawCircle(randomWidth, randomHeight + radius/2f, radius, paint);
}
public boolean onTouch(View v, MotionEvent event) {
int x = (int) event.getX();
int y = (int) event.getY();
if(isInsideCircle(x, y) == true){
//Do your things here
if(redColor == lastColor){
Activity.setContentView(R.layout.youfailed);
} else {
addPoints++;
}
}else {
}
return true;
}
private boolean isInsideCircle(int x, int y){
if ((((x - randomWidth)*(x - randomWidth)) + ((y - randomHeight)*(y - randomHeight))) < ((radius)*(radius)))
return true;
return false;
}
}
The error shows up in this method
public boolean onTouch(View v, MotionEvent event) {
int x = (int) event.getX();
int y = (int) event.getY();
if(isInsideCircle(x, y) == true){
//Do your things here
if(redColor == lastColor){
//it shows up right below here
Activity.setContentView(R.layout.youfailed);
} else {
addPoints++;
}
}else {
}
return true;
}

Your problem is this line:
Activity.setContentView(R.layout.youfailed);
it doesn't work this way.
You need an actual activity to set the content view. setContentView is not a static method.
UPDATE:
You seem to try to change the content of an Activity from within one of it's Child-View objects, which is very bad style and should not be done.
A View should never have control over what it's parent actually displays.
However, a callback into the parent could solve your issue.
A callback is simply an interface with one or more methods, in your case one: "onFailure()", and it would be implemented by e.g. the Activity. This "onFailure()" is called in your onTouch() instead of the setContentView(), and within your actual Activity's implementation (which has to register itself as a callback receiver just like you do with onClickListeners or onTouchListeners), you can do whatever you like.
Example for a Callback-Interface:
public interface FailureCallback {
public void onFailure();
}
You can put that as an internal interface into your DrawingView class. In your DrawingView class, you'll need a setter for the actual callback-instance and then you can call from within the onTouch() method.
In your implementation of the callback, you should not change the content of the running activity, btw - instead consider calling a new Activity using startActivity(...).

Android vertical scroll

I have class, which draw many crosses in vertical way. I want learn how do this, so I try it on this simple example:
public class Draw extends View {
Paint paint = new Paint();
public Draw(Context context) {
super(context);
paint.setColor(Color.BLACK);
}
#Override
public void onDraw(Canvas canvas) {
int x = 1;
for(int i = 0; i < 100; i++){
if (i%2 == 0) x = 2;
else x=1;
canvas.drawLine(0, 0 + x*i*20, 20, 20 + x*i*20, paint);
canvas.drawLine(20, 0 + x*i*20, 0, 20 + x*i*20, paint);
}
}
}
and I want scroll it.
I implemented onTouchEvent with MotionEvent.ACTION_MOVE:
public class DrawActivity extends Activity {
private Draw dv;
private float xDistance, yDistance, lastX, lastY;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
dv = new Draw(this);
setContentView(dv);
}
public boolean onTouchEvent(MotionEvent event) {
int action = MotionEventCompat.getActionMasked(event);
switch (action) {
case (MotionEvent.ACTION_MOVE):
final float curX = event.getX();
final float curY = event.getY();
xDistance += Math.abs(curX - lastX);
yDistance += Math.abs(curY - lastY);
lastX = curX;
lastY = curY;
if (xDistance > yDistance)
return false;
default:
return super.onTouchEvent(event);
}
}
}
but it not working. How Can I scroll a canvas?

Since you are extending View you should update it's scrollX value (or store itself) and translate the content of the drawing by its value.