public class MovingBagView extends View {
private Bitmap bag[] = new Bitmap[2];
private int bagX;
private int bagY = 1000;
private int bagSpeed;
private Boolean touch = false;
private int canvasWidth, canvasHeight;
private Bitmap backgroundImage;
private Paint scorePaint = new Paint();
private Bitmap life[] = new Bitmap[2];
public MovingBagView(Context context) {
super(context);
bag[0] = BitmapFactory.decodeResource(getResources(), R.drawable.bag1);
bag[1] = BitmapFactory.decodeResource(getResources(), R.drawable.bag2);
backgroundImage = BitmapFactory.decodeResource(getResources(), R.drawable.background);
scorePaint.setColor(Color.BLACK);
scorePaint.setTextSize(40);
scorePaint.setTypeface(Typeface.DEFAULT_BOLD);
scorePaint.setAntiAlias(true);
life[0] = BitmapFactory.decodeResource(getResources(), R.drawable.heart);
life[1] = BitmapFactory.decodeResource(getResources(), R.drawable.heart_grey);
bagX = 10;
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvasWidth = canvas.getWidth();
canvasHeight = canvas.getHeight();
canvas.drawBitmap(backgroundImage, 0, 0, null);
int minBagX = bag[0].getWidth();
int maxBagX = canvasWidth - bag[0].getWidth() * 3;
bagX = bagX + bagSpeed;
if (bagX < minBagX) {
bagX = minBagX;
}
if (bagX < maxBagX) {
bagX = maxBagX;
}
bagSpeed = bagSpeed + 2;
if (touch) {
canvas.drawBitmap(bag[1], bagX, bagY, null);
}
else {
canvas.drawBitmap(bag[0], bagX, bagY, null);
}
canvas.drawText("Score : ", 20, 60, scorePaint);
canvas.drawBitmap(life[0], 500, 10, null);
canvas.drawBitmap(life[0], 570, 10, null);
canvas.drawBitmap(life[0], 640, 10, null);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
touch = true;
bagSpeed = -12;
}
return true;
}
}
I can tap on the screen to move the object to the left, and the more I tap on it, the further it should move to the left. However, the problem is that the object moves too much to the right, and goes off the screen. I want it to stop at the edge, so its still visible on the screen. Furthermore, the object is positioned in the center bottom of the screen, how do I position it to the bottom left corner? You can see how it works by looking at the GIF below.
This condition is never applied on the code you've provided. It continues to exceed the max value.
if (bagX < maxBagX) {
bagX = maxBagX;
}
It should look like this:
if (bagX >= maxBagX) {
bagX = maxBagX;
}
And the maxBagX value should be canvasWidth - bag[0].getWidth()
in order to achieve the right edge of the bag itself. (Unless you're using the multiply 3 times for a different reason, this should be the solution.)