I created two bitmap on my view using the following class (Simple 2D Graphics in android) and wandering to achieve that bitmap can move independently. I am calling motionevent method for this.
Current issue, i do not understand why does only one object is moving right in the following code. e.g. with this code, only "not" bitmap is moved, i would like to move both bitmaps independently of eachother.
scenrio: i can use my two fingures, one for each object, to move the bitmaps independently. but i don't know how to achieve this.
public class TouchView extends View {
private Drawable cross;
private Rect crossBounds = null;
private Drawable not;
private Rect notBounds = null;
private int x1, y1, x2, y2 ;
boolean flag = true;
private void intialize ()
{
int w1 = cross.getIntrinsicWidth();
int h1 = cross.getIntrinsicHeight();
x1 = 100;
y1 = 100;
crossBounds = new Rect(x1-w1/2, y1-w1/2, x1+w1/2, y1+h1/2);
int w = not.getIntrinsicWidth();
int h = not.getIntrinsicHeight();
x2 = 300;
y2 = 300;
notBounds = new Rect(x2-w/2, y2-w/2, x2+w/2, y2+h/2);
}
public TouchView(Context context) {
super(context);
// Get a representation of the image
Resources resources = context.getResources();
cross = (Drawable) resources.getDrawable(R.drawable.cross);
not = (Drawable) resources.getDrawable(R.drawable.not);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
Log.i("TouchView.onTouchEvent", "event = " + event);
if(event.getAction() == MotionEvent.ACTION_DOWN ||
event.getAction() == MotionEvent.ACTION_MOVE) {
int touchCounter = event.getPointerCount();
if (touchCounter ==2 && getHeight ()==y1){
int w = cross.getIntrinsicWidth();
int h = cross.getIntrinsicHeight();
x1 = (int) event.getX();
crossBounds = new Rect(x1-w/2, y1-w/2, x1+w/2, y1+h/2);
}
else
{
int w1 = not.getIntrinsicWidth();
int h1 = not.getIntrinsicHeight();
x2 = (int) event.getX();
notBounds = new Rect(x2-w1/2, y2-w1/2, x2+w1/2, y2+h1/2);
}
// Request the system to redraw the view (call onDraw at
// some point in the future)
// From a non-UI thread, call postInvalidate instead
invalidate();
return true;
}
return false;
}
@Override
protected void onDraw(Canvas canvas) {
Log.i("TouchView.onDraw", "");
// Background
Paint bgPaint = new Paint();
bgPaint.setColor(Color.WHITE);
canvas.drawPaint(bgPaint);
if (flag == true){
intialize ();
cross.setBounds(crossBounds);
cross.draw(canvas);
not.setBounds(notBounds);
not.draw(canvas);
flag=false;
}
if(crossBounds != null) {
cross.setBounds(crossBounds);
cross.draw(canvas);
not.setBounds(notBounds);
not.draw(canvas);
}
}
}
public class SimpleDrag extends View {
private final int INVALID_INDEX = -1;
private final int mTotalItems = 5;
private ArrayList<Rect> mItemsCollection;
private ArrayList<Point> mActiveDragPoints;
private ArrayList<Rect> mActiveRects;
private Paint mPaint;
/**
* @param context
* @return of type SimpleDrag
* Constructor function
* @since Feb 19, 2013
* @author rajeshcp
*/
public SimpleDrag(Context context) {
super(context);
init();
}
/**
* @param context
* @param attrs
* @return of type SimpleDrag
* Constructor function
* @since Feb 19, 2013
* @author rajeshcp
*/
public SimpleDrag(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
/**
* @param context
* @param attrs
* @param defStyle
* @return of type SimpleDrag
* Constructor function
* @since Feb 19, 2013
* @author rajeshcp
*/
public SimpleDrag(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
/* (non-Javadoc)
* @see android.view.View#onDraw(android.graphics.Canvas)
* @since Feb 19, 2013
* @author rajeshcp
*/
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawColor(Color.BLUE, PorterDuff.Mode.CLEAR);
for( Rect rect : mItemsCollection)
{
canvas.drawRect(rect, mPaint);
}
}
/**
* @param of type null
* @return of type null
* function which will initialize the view
* @since Feb 20, 2013
* @author rajeshcp
*/
private void init()
{
mActiveRects = new ArrayList<Rect>(mTotalItems);
mActiveDragPoints = new ArrayList<Point>(mTotalItems);
mItemsCollection = new ArrayList<Rect>();
for( int i = 0; i < mTotalItems; i++)
{
Rect rect = new Rect(i * 100, i * 100, (i + 1) * 100, (i + 1) * 100);
mItemsCollection.add(rect);
}
mPaint = new Paint(Paint.FILTER_BITMAP_FLAG | Paint.DITHER_FLAG | Paint.ANTI_ALIAS_FLAG);
mPaint.setColor(Color.RED);
}
/* (non-Javadoc)
* @see android.view.View#onTouchEvent(android.view.MotionEvent)
* @since Feb 19, 2013
* @author rajeshcp
*/
@Override
public boolean onTouchEvent(MotionEvent event) {
final int action = event.getActionMasked();
final int pointer = event.getActionIndex();
switch (action) {
case MotionEvent.ACTION_DOWN :
Point touchDown = new Point((int)event.getX(), (int)event.getY());
lookForIntersection(touchDown);
break;
case MotionEvent.ACTION_UP :
case MotionEvent.ACTION_CANCEL :
mActiveDragPoints.removeAll(mActiveDragPoints);
mActiveRects.removeAll(mActiveRects);
break;
case MotionEvent.ACTION_MOVE :
int count = 0;
for(Rect rect : mActiveRects)
{
Point curretPoint = new Point((int)event.getX(count), (int)event.getY(count));
moveRect(curretPoint, mActiveDragPoints.get(count), rect);
count++;
}
Log.d(getClass().getName(), "Active Rects" + mActiveRects.size());
Log.d(getClass().getName(), "Active Points" + mActiveDragPoints.size());
invalidate();
break;
case MotionEvent.ACTION_POINTER_DOWN :
touchDown = new Point((int)event.getX(pointer), (int)event.getY(pointer));
lookForIntersection(touchDown);
//Log.d(getClass().getName(), "ACTION_POINTER_DOWN" + pointer);
break;
case MotionEvent.ACTION_POINTER_UP :
int index = getIntersectionRectIndex(new Point((int)event.getX(pointer), (int)event.getY(pointer)));
if( index != INVALID_INDEX )
{
Rect rect = mItemsCollection.get(index);
mActiveDragPoints.remove(mActiveRects.indexOf(rect));
mActiveRects.remove(rect);
}
break;
default:
break;
}
return true;
}
/**
* @param touchDown of type Point
* @return of type null
* function which will find the
* intersecting rect and add to the
* active collection
* @since Feb 20, 2013
* @author rajeshcp
*/
private void lookForIntersection(Point touchDown)
{
final int index = getIntersectionRectIndex(touchDown);
if( index != INVALID_INDEX )
{
final Rect rect = mItemsCollection.get(index);
if( mActiveRects.indexOf(rect) == INVALID_INDEX )
{
mActiveDragPoints.add(touchDown);
mActiveRects.add(mItemsCollection.get(index));
}
}
Log.d(getClass().getName(), "Active Rects" + mActiveRects.size());
Log.d(getClass().getName(), "Active Points" + mActiveDragPoints.size());
}
/**
* @param point of type Point
* @return of type int
* function which will return the index of
* the rect contaning the given point
* @since Feb 20, 2013
* @author rajeshcp
*/
private int getIntersectionRectIndex(final Point point)
{
int index = INVALID_INDEX;
for(Rect rect : mItemsCollection)
{
if( rect.contains(point.x, point.y) )
{
index = mItemsCollection.indexOf(rect);
break;
}
}
return index;
}
/**
* @param currentPoint of type Point
* @param prevPoint of type Point
* @param rect of type Rect
* @return of type null
* function which will move the change the
* bounds of teh rect
* @since Feb 20, 2013
* @author rajeshcp
*/
private void moveRect(Point currentPoint, Point prevPoint, final Rect rect)
{
int xMoved = currentPoint.x - prevPoint.x;
int yMoved = currentPoint.y - prevPoint.y;
rect.set(rect.left + xMoved, rect.top + yMoved, rect.right + xMoved, rect.bottom + yMoved);
mActiveDragPoints.set(mActiveDragPoints.indexOf(prevPoint), currentPoint);
}
}
Hope this is what you want, haven't tested a lot, but basically this is working for me even you can increase the nof items by changing the mTotalItems. Hope this will help.