I have already searched alot around here but haven't found a solution yet. So the thing is , I have a image 3000*3000 px, I set it to scale type matrix. Now I have only the left corner showing of the image. Now I don't want people to zoom in at this stage, only zoom out to a maximum of 'x' (Still have to see how much).
It's the imageview "kaart" that has to be zoomed.
question : How to let people only zoom out in the beginning and don't let them pass x ?and afterwards, don't let them zoom in more than the original size
i've tried with negative values , but that didn't work
Here is my code:
// These matrices will be used to move and zoom image
Matrix matrix = new Matrix();
Matrix savedMatrix = new Matrix();
// max and min zoom
//private static final float MIN_ZOOM = 1.0f;
//private static final float MAX_ZOOM = 5.0f;
//scale = Math.max(MIN_ZOOM, Math.min(scale, MAX_ZOOM));
// We can be in one of these 3 states
static final int NONE = 0;
static final int DRAG = 1;
static final int ZOOM = 2;
int mode = NONE;
// Remember some things for zooming
PointF start = new PointF();
PointF mid = new PointF();
float oldDist = 1f;
String savedItemClicked;
ImageView view;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.kaart);
view = (ImageView) findViewById(R.id.kaart);
view.setOnTouchListener(this);
}
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
ImageView view = (ImageView) v;
dumpEvent(event);
// Handle touch events here...
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
savedMatrix.set(matrix);
start.set(event.getX(), event.getY());
//Log.d(TAG, "mode=DRAG");
mode = DRAG;
break;
case MotionEvent.ACTION_POINTER_DOWN:
oldDist = spacing(event);
//Log.d(TAG, "oldDist=" + oldDist);
if (oldDist > 10f) {
savedMatrix.set(matrix);
midPoint(mid, event);
mode = ZOOM;
//Log.d(TAG, "mode=ZOOM");
}
break;
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_POINTER_UP:
mode = NONE;
// Log.d(TAG, "mode=NONE");
break;
case MotionEvent.ACTION_MOVE:
if (mode == DRAG) {
// ...
matrix.set(savedMatrix);
matrix.postTranslate(event.getX() - start.x, event.getY()
- start.y);
} else if (mode == ZOOM) {
float newDist = spacing(event);
// Log.d(TAG, "newDist=" + newDist);
if (newDist > 10f) {
matrix.set(savedMatrix);
float scale = newDist / oldDist;
matrix.postScale(scale, scale, mid.x, mid.y);
}
}
break;
}
limitZoom(matrix);
limitDrag(matrix);
view.setImageMatrix(matrix);
return true;
}
@SuppressWarnings("deprecation")
private void dumpEvent(MotionEvent event) {
String names[] = { "DOWN", "UP", "MOVE", "CANCEL", "OUTSIDE",
"POINTER_DOWN", "POINTER_UP", "7?", "8?", "9?" };
StringBuilder sb = new StringBuilder();
int action = event.getAction();
int actionCode = action & MotionEvent.ACTION_MASK;
sb.append("event ACTION_").append(names[actionCode]);
if (actionCode == MotionEvent.ACTION_POINTER_DOWN
|| actionCode == MotionEvent.ACTION_POINTER_UP) {
sb.append("(pid ").append(
action >> MotionEvent.ACTION_POINTER_ID_SHIFT);
sb.append(")");
}
sb.append("[");
for (int i = 0; i < event.getPointerCount(); i++) {
sb.append("#").append(i);
sb.append("(pid ").append(event.getPointerId(i));
sb.append(")=").append((int) event.getX(i));
sb.append(",").append((int) event.getY(i));
if (i + 1 < event.getPointerCount())
sb.append(";");
}
sb.append("]");
// Log.d(TAG, sb.toString());
}
/** Determine the space between the first two fingers */
private float spacing(MotionEvent event) {
float x = event.getX(0) - event.getX(1);
float y = event.getY(0) - event.getY(1);
return FloatMath.sqrt(x * x + y * y);
}
/** Calculate the mid point of the first two fingers */
private void midPoint(PointF point, MotionEvent event) {
float x = event.getX(0) + event.getX(1);
float y = event.getY(0) + event.getY(1);
point.set(x / 2, y / 2);
}
}
Hope someone can help me. I would really apreciate it.
EDIT
I have added 2 functions i found somewhere.
private void limitZoom(Matrix m) {
float[] values = new float[9];
m.getValues(values);
float scaleX = values[Matrix.MSCALE_X];
float scaleY = values[Matrix.MSCALE_Y];
if(scaleX > MAX_ZOOM) {
scaleX = MAX_ZOOM;
} else if(scaleX < MIN_ZOOM) {
scaleX = MIN_ZOOM;
}
if(scaleY > MAX_ZOOM) {
scaleY = MAX_ZOOM;
} else if(scaleY < MIN_ZOOM) {
scaleY = MIN_ZOOM;
}
values[Matrix.MSCALE_X] = scaleX;
values[Matrix.MSCALE_Y] = scaleY;
m.setValues(values);
}
and
private void limitDrag(Matrix m) {
float[] values = new float[9];
m.getValues(values);
float transX = values[Matrix.MTRANS_X];
float transY = values[Matrix.MTRANS_Y];
float scaleX = values[Matrix.MSCALE_X];
float scaleY = values[Matrix.MSCALE_Y];
ImageView iv = (ImageView)findViewById(R.id.kaart);
Rect bounds = iv.getDrawable().getBounds();
int viewWidth = getResources().getDisplayMetrics().widthPixels;
int viewHeight = getResources().getDisplayMetrics().heightPixels;
int width = bounds.right - bounds.left;
int height = bounds.bottom - bounds.top;
float minX = (-width + 20) * scaleX;
float minY = (-height + 20) * scaleY;
if(transX > (viewWidth - 20)) {
transX = viewWidth - 20;
} else if(transX < minX) {
transX = minX;
}
if(transY > (viewHeight - 80)) {
transY = viewHeight - 80;
} else if(transY < minY) {
transY = minY;
}
values[Matrix.MTRANS_X] = transX;
values[Matrix.MTRANS_Y] = transY;
m.setValues(values);
}
I have to call these functions right after the switch case and just before is set the imagematrix on my view. (I have added this to my previous code here above)
maybe this isn't the best solution , but it works .
