试试这段代码，应该会有所帮助： -
case MotionEvent.ACTION_MOVE:
if (mode == ZOOM) {
float newDist = spacing(event);
double zoomDist = newDist-oldDist;
if(zoomDist > 0){
if(zoomDist > 50 && zoomDist <= 200){
if (curZoomLevel < mZoomMax && gestureZoom == 0) {
gestureZoom ++;
GestureZoomIn();
}
}else if(zoomDist > 200 && zoomDist <= 300){
if (curZoomLevel < mZoomMax && gestureZoom == 1) {
gestureZoom ++;
GestureZoomIn();
}
}else if(zoomDist > 300 && zoomDist <= 400){
if (curZoomLevel < mZoomMax && gestureZoom == 2) {
gestureZoom++;
GestureZoomIn();
}
//zoomin
private void GestureZoomIn(){
if (mParameters.isZoomSupported()){
mZoomMax = mParameters.getMaxZoom();
if (zoom_text_value
zoom_text_value++;
curZoomLevel++;
zoom_float=zoom_float+0.5;
onZoomValueChanged(curZoomLevel);
//zoomout
private void GestureZoomOut(){
if (mParameters.isZoomSupported()){
if (0
zoom_text_value--;
curZoomLevel--;
zoom_float=zoom_float-0.5;
onZoomValueChanged(curZoomLevel);
由于
