public void onClick(View v) {
    if (v == zoomInButton) {
      if (mapThreadRunning) return; // no updates when download is running

      float w, h;

      mScaleFactor *= 2.0;
      matrix.postScale(2.0f, 2.0f);
      w = scrWidth / 2.0f;
      h = scrHeight / 2.0f;

      matrix.postTranslate(-w, -h);
      imgOffsetX -= w;
      imgOffsetY -= h;

      breakMapThread = true;
      restartMap();
    } else if (v == zoomOutButton) {
      if (mapThreadRunning) return; // no updates when download is running

      float w, h;

      mScaleFactor *= 0.5;
      matrix.postScale(0.5f, 0.5f);
      w = scrWidth * 2.0f;
      h = scrHeight * 2.0f;

      matrix.postTranslate(w, h);
      imgOffsetX += w;
      imgOffsetY += h;

      breakMapThread = true;
      restartMap();
    }
    updateUI(true);
  }
  public boolean onTouchEvent(MotionEvent ev) {
    if (mapThreadRunning) return false; // no updates when download is running
    if (gestureDetector.onTouchEvent(ev)) return true;

    final int action = ev.getAction();
    switch (action & MotionEvent.ACTION_MASK) {
      case MotionEvent.ACTION_DOWN:
        {
          mLastTouchX = ev.getX();
          mLastTouchY = ev.getY();
          mActivePointerId = ev.getPointerId(0);
          break;
        }
      case MotionEvent.ACTION_POINTER_DOWN:
        {
          mLastTouchX2 = ev.getX();
          mLastTouchY2 = ev.getY();
          if (ev.getPointerCount() > 1) mActivePointerId2 = ev.getPointerId(1);
          break;
        }
      case MotionEvent.ACTION_MOVE:
        {
          int pointerIndex;
          float x = 0.0f, y = 0.0f;

          try {
            if ((mActivePointerId != INVALID_POINTER_ID)
                || (mActivePointerId2 != INVALID_POINTER_ID)) {
              pointerIndex = ev.findPointerIndex(mActivePointerId);
              x = ev.getX(pointerIndex);
              y = ev.getY(pointerIndex);
            }
            if ((mActivePointerId != INVALID_POINTER_ID)
                && (mActivePointerId2 != INVALID_POINTER_ID)) {
              double d1, d2;

              pointerIndex = ev.findPointerIndex(mActivePointerId2);
              if (pointerIndex < 0) return false;
              float x2 = ev.getX(pointerIndex);
              float y2 = ev.getY(pointerIndex);

              d1 = java.lang.Math.sqrt((x - x2) * (x - x2) + (y - y2) * (y - y2));
              d2 =
                  java.lang.Math.sqrt(
                      (mLastTouchX - mLastTouchX2) * (mLastTouchX - mLastTouchX2)
                          + (mLastTouchY - mLastTouchY2) * (mLastTouchY - mLastTouchY2));

              /*                  if ((Math.abs(d1)>300) || (Math.abs(d2)>300))
              {
                 int i=0;
                 i=i;
              }*/

              if ((d1 > 0) && (d2 > 0)) {
                float w, h, s;

                s = (float) (d1 / d2);
                mScaleFactor *= s;
                matrix.postScale(s, s);
                w = scrWidth / 2.0f;
                h = scrHeight / 2.0f;

                matrix.postTranslate(w, h);
                imgOffsetX += w;
                imgOffsetY += h;
              }

              mLastTouchX2 = x2;
              mLastTouchY2 = y2;
            } else if (mScaleFactor == 1.0) {
              mScaleFactor = 1.0f;
              imgOffsetX += (x - mLastTouchX);
              imgOffsetY += (y - mLastTouchY);
              matrix.setTranslate(imgOffsetX, imgOffsetY);
            }

            if ((mActivePointerId != INVALID_POINTER_ID)
                || (mActivePointerId2 != INVALID_POINTER_ID)) {
              mLastTouchX = x;
              mLastTouchY = y;
            }
          } catch (Exception e) {
            // can be caused by
            // pointerIndex= ev.findPointerIndex(mActivePointerId);
            // x= ev.getX(pointerIndex);
            // above which seems to be a Android bug
          }
          invalidate();
          break;
        }
      case MotionEvent.ACTION_UP:
      case MotionEvent.ACTION_POINTER_UP:
        {
          breakMapThread = true;
          mActivePointerId = INVALID_POINTER_ID;
          mActivePointerId2 = INVALID_POINTER_ID;
          restartMap();
          break;
        }
    }
    return true;
  }