如何执行捏缩放或在android中捏缩小 [英] How to get if pinch zoom in is performed or pinch zoom out in android
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问题描述
我在使用自定义mapView的应用程序中工作，如果用户捏住（两个手指手势），则在该mapView上，地图的相机位置应相应更改，例如。如果用户捏放大，相机变焦应该放大地图（仅屏幕中心），如果用户捏缩小，相机缩放应缩小地图（仅屏幕中心）。我已经尝试过，但是放大和缩小地图总是放大。有没有什么办法可以找到两个手指之间的距离是增加还是减少，或者手势是捏缩小还是捏放大??
更新
MainActivity.java
public class MainActivity extends AppCompatActivity {
private static final String TAG = MainActivity.class.getSimpleName（）;
private static final int LOCATION_PERMISSION_CONSTANT = 34;
private static final int REQUEST_CHECK_SETTINGS = 12;
// private EnhanchedMapView mapView;
私人MapView地图查看;
私人GoogleMap googleMap;
private FusedLocationProviderClient mFusedLocationClient;
私人位置mLastLocation;
LocationManager locationManager;
私人TextView tvCoordinates;
私有GoogleApiClient googleApiClient;
@Override
保护无效的onCreate（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）;
setContentView（R.layout.activity_main）;
bindUI（）;
mapView.onCreate（savedInstanceState）;
fusedLocationMethod（savedInstanceState）;
getLocationPermission（）;
// getLastLocation（）;
}
private void bindUI（）{
mapView = findViewById（R.id.map_view）;
tvCoordinates = findViewById（R.id.tv_coordinates）;
public void fusedLocationMethod（Bundle savedInstanceState）{
mFusedLocationClient = LocationServices.getFusedLocationProviderClient（this）;
$ b $ private void getLocationPermission（）{
if（ActivityCompat.checkSelfPermission（this，android.Manifest.permission.ACCESS_FINE_LOCATION）
！= PackageManager.PERMISSION_GRANTED& & ActivityCompat.checkSelfPermission（this，android.Manifest.permission.ACCESS_COARSE_LOCATION）！= PackageManager.PERMISSION_GRANTED）{
ActivityCompat.requestPermissions（this，
new String [] {android.Manifest.permission.ACCESS_FINE_LOCATION， android.Manifest.permission.ACCESS_COARSE_LOCATION}，
LOCATION_PERMISSION_CONSTANT）;
return;
}
getLastLocation（）;
$ b @Override
public void onRequestPermissionsResult（int requestCode，
String permissions []，int [] grantResults）{
switch（requestCode）{
case LOCATION_PERMISSION_CONSTANT：
//如果请求被取消，结果数组为空。 $ b $ if（grantResults.length> 0
&&& amp; grantResults [0] == PackageManager.PERMISSION_GRANTED）{
if（googleApiClient == null）{
getLocationPermission（） ;
} else {
getLocationPermission（）;
}
} else {
Toast.makeText（this，Permission Denied，Toast.LENGTH_SHORT）.show（）;
}
break;
$ b public void getLastLocation（）{
if（ActivityCompat.checkSelfPermission（this，Manifest.permission.ACCESS_FINE_LOCATION）！= PackageManager。 PERMISSION_GRANTED&& ActivityCompat.checkSelfPermission（this，Manifest.permission.ACCESS_COARSE_LOCATION）！= PackageManager.PERMISSION_GRANTED）{
return;
mFusedLocationClient.getLastLocation（）
.addOnSuccessListener（this，new OnSuccessListener< Location>（）{
@Override
public void onSuccess（Location location）{
if（location == null）{
Log.w（TAG，onSuccess：null）;
return;
}
mLastLocation = location ;
preLat = location.getLatitude（）;
preLong = location.getLongitude（）;
settingMap（location.getLatitude（），location.getLongitude（））;
try {
locationManager =（LocationManager）getSystemService（Context.LOCATION_SERVICE）;
} catch（Exception e）{
e.printStackTrace（）;
Log.d（Error，e.getMessage（）+203）; （ActivityActivity.checkSelfPermission（MainActivity.this，Manifest.permission.ACCESS_FINE_LOCATION）！= PackageManager.PERMISSION_GRANTED&&& ActivityCompat.checkSelfPermission（MainActivity.this，Manifest.permission。 ACCESS_COARSE_LOCATION）！= PackageManager.PERMISSION_GRANTED）{
return;
$ b $）
.addOnFailureListener（this，new OnFailureListener（）{
@Override
public void onFailure（@NonNull例外e）{
Log.w（TAG，getLastLocation：onFailure，e）;
}
}）;
}
private double preLat = 0.0;
private double preLong = 0.0;
//设置地图
private void settingMap（final double lat，final double longi）{
mapView.getMapAsync（new OnMapReadyCallback（）{
@Override
public void onMapReady（GoogleMap gglmap）{
googleMap = gglmap;
googleMap.getUiSettings（）。setAllGesturesEnabled（false）;
googleMap.clear（）;
CameraPosition cameraPosition = new CameraPosition.Builder（）。target（new LatLng（lat，longi））。zoom（16）.build（）;
googleMap.moveCamera（CameraUpdateFactory.newCameraPosition（cameraPosition））;
googleMap.getUiSettings（）。setMyLocationButtonEnabled（false）;
//位置许可
if （ActivityCompat.checkSelfPermission（MainActivity.this，Manifest.permission.ACCESS_FINE_LOCATION）！= PackageManager.PERMISSION_GRANTED&&& ActivityCompat.checkSelf Permission（MainActivity.this，Manifest.permission.ACCESS_COARSE_LOCATION）！= PackageManager.PERMISSION_GRANTED）{
return;
}
googleMap.setMyLocationEnabled（true）;
//googleMap.getUiSettings().setAllGesturesEnabled(false）;
googleMap.setOnCameraIdleListener（new GoogleMap.OnCameraIdleListener（）{
@Override
public void onCameraIdle（）{
$ b $ int mapViewHeight = mapView.getHeight（）;
int mapViewWidth = mapView.getWidth（）;
Projection projection = googleMap.getProjection（）;
LatLng geographicPosition = projection.fromScreenLocation（new Point（mapViewWidth / 2， mapViewHeight / 2））;
// Toast.makeText（getActivity（），+ geographicPosition.latitude +，+ geographicalPosition.longitude，Toast.LENGTH_LONG）.show（）;
tvCoordinates.setText（geographicPosition.latitude +，+ geographicPosition.longitude）;
}
}）;
}
}）;
$ b @Override
public void onResume（）{
super.onResume（）;
mapView.onResume（）;
$ b @Override
public void onSaveInstanceState（Bundle savedInstanceState）{
super.onSaveInstanceState（savedInstanceState）;
mapView.onSaveInstanceState（savedInstanceState）;
}
@Override
public void onPause（）{
super.onPause（）;
mapView.onPause（）;
}
@Override
public void onStop（）{
super.onStop（）;
mapView.onStop（）;
@Override
public void onLowMemory（）{
super.onLowMemory（）;
mapView.onLowMemory（）;
}
@Override
public void onDestroy（）{
super.onDestroy（）;
mapView.onDestroy（）;
}
@Override
public void onStart（）{
super.onStart（）;
mapView.onStart（）;
$ b $ p EnhancedMapView.java
public class EnhanchedMapView扩展MapView实现OnMapReadyCallback {
private long mLastTouchTime = -1;
private static final int INVALID_POINTER_ID = -1;
私人OnMapReadyCallback mMapReadyCallback;
私人GoogleMap mGoogleMap;
私有浮动mPosX;
私有浮动mPosY;
私人浮动mLastTouchX;
私人浮动mLastTouchY;
private int mActivePointerId = INVALID_POINTER_ID;
private void init（）{
}
@Override
public void getMapAsync（OnMapReadyCallback callback）{
mMapReadyCallback = callback;
super.getMapAsync（this）;
}
@Override
public void onMapReady（GoogleMap googleMap）{
mGoogleMap = googleMap;
}
LatLng geographicPosition;
boolean isPinch = false;
@Override
public boolean dispatchTouchEvent（MotionEvent event）{
switch（event.getAction（）& MotionEvent.ACTION_MASK）{
case MotionEvent.ACTION_DOWN：
mGoogleMap.getUiSettings（）。setScrollGesturesEnabled（true）;
long thisTime = System.currentTimeMillis（）;
if（thisTime - mLastTouchTime< ViewConfiguration.getDoubleTapTimeout（））{
if（mGoogleMap！= null）{
LatLng zoomCenter = mGoogleMap.getProjection（）。fromScreenLocation（new Point（（int）event.getX（），（int）event.getY（）））;
float currentZoom = mGoogleMap.getCameraPosition（）。zoom;
int mapViewHeight = getHeight（）;
int mapViewWidth = getWidth（）;
投影投影= mGoogleMap.getProjection（）;
geographicPosition = projection.fromScreenLocation（new Point（mapViewWidth / 2，mapViewHeight / 2））;
MarkerOptions markerOptions = new MarkerOptions（）;
markerOptions.position（geographicPosition）;
mGoogleMap.addMarker（markerOptions）;
mGoogleMap.moveCamera（CameraUpdateFactory.newLatLngZoom（new LatLng（geographicPosition.latitude，geographicalPosition.longitude），currentZoom + 1））;
}
mLastTouchTime = -1;
} else {
mLastTouchTime = thisTime;
mGoogleMap.getUiSettings（）。setZoomGesturesEnabled（false）;
}
break;
case MotionEvent.ACTION_POINTER_DOWN：
mGoogleMap.getUiSettings（）。setZoomGesturesEnabled（false）;
mGoogleMap.getUiSettings（）。setScrollGesturesEnabled（false）;
Log.d（Nirmal，ACTION_POINTER_DOWN）;
isPinch = true;
int mapViewHeight = getHeight（）;
int mapViewWidth = getWidth（）;
投影投影= mGoogleMap.getProjection（）;
geographicPosition = projection.fromScreenLocation（new Point（mapViewWidth / 2，mapViewHeight / 2））;
break;
case MotionEvent.ACTION_POINTER_UP：
mGoogleMap.getUiSettings（）。setScrollGesturesEnabled（true）;
isPinch = false;
休息;
case MotionEvent.ACTION_UP：
mGoogleMap.getUiSettings（）。setScrollGesturesEnabled（true）;
休息;
case MotionEvent.ACTION_MOVE：
if（isPinch）{
if（mGoogleMap == null || geographicPosition == null）
break;
//Log.d( \"Nirmal，ACTION_MOVE）;
Log.d（Nirmal，+ event.getX（）+，+ event.getY（））;
float currentZoom = mGoogleMap.getCameraPosition（）。zoom;
mGoogleMap.moveCamera（CameraUpdateFactory.newLatLngZoom（new LatLng（geographicPosition.latitude，geographicPosition.longitude），currentZoom + 0.05f））;
}
break;
}
返回super.dispatchTouchEvent（event）;
}
}
解决方案建议使用 pskink ，您需要 ScaleGestureDetector 对象，它确定缩放方向。类似的东西：
$ b $ pre $ code ScaleGestureDetector mScaleDetector = new ScaleGestureDetector（getContext（），$ b $ newScaleGestureDetector.SimpleOnScaleGestureListener（）{
私人浮动scaleFactor = 1f;
@Override
公共布尔onScale（ScaleGestureDetector检测器）{
//检测缩放的商店比例因子方向
scaleFactor = detector.getScaleFactor（）;
返回true;
}
$ b $ @覆盖
public void onScaleEnd（ScaleGestureDetector检测器）{
float currentZoom = mGoogleMap.getCameraPosition（）。zoom;
if（scaleFactor> 1）{
//放大检测
m GoogleMap.moveCamera（CameraUpdateFactory.newLatLngZoom（mZoomCenter，currentZoom + 1））;
} else if（scaleFactor< 1）{
// zoom out detected
mGoogleMap.moveCamera（CameraUpdateFactory.newLatLngZoom（mZoomCenter，currentZoom - 1））;
}
super.onScaleEnd（detector）;
}
}）;
您可以在 EnhanchedMapView.dispatchTouchEvent（） b
$ b $ $ $
$
$覆盖
public boolean dispatchTouchEvent（MotionEvent事件） {
//只需在您的ScaleGestureDetector对象上调用.onTouchEvent（）
mScaleDetector.onTouchEvent（event）;
switch（event.getAction（）& MotionEvent.ACTION_MASK）{
...
注意！您需要禁用 GoogleMap 缩放手势
@Override
public void onMapReady（GoogleMap googleMap）{
mGoogleMap = googleMap;
mGoogleMap.getUiSettings（）。setZoomGesturesEnabled（false）;
...
}
并且永远不会启用它。
I'm working on an application in which I have used custom mapView, and on that mapView if user pinch(two finger gesture), the camera position for map should change accordingly, for eg. if user pinch zoom in, the camera zoom should zoom in for map (only center of the screen) and if user pinch zoom out, the camera zoom should be zoom out for the map(only center of the screen). I've tried for it but for zoom in and zoom out the map is always zooming in. Is there any way to find the distance between two finger that is increasing/decreasing, or gesture is pinch zoom out or pinch zoom in??
UPDATE
MainActivity.java
public class MainActivity extends AppCompatActivity {
private static final String TAG = MainActivity.class.getSimpleName();
private static final int LOCATION_PERMISSION_CONSTANT = 34;
private static final int REQUEST_CHECK_SETTINGS = 12;
//private EnhanchedMapView mapView;
private MapView mapView;
private GoogleMap googleMap;
private FusedLocationProviderClient mFusedLocationClient;
private Location mLastLocation;
LocationManager locationManager;
private TextView tvCoordinates;
private GoogleApiClient googleApiClient;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
bindUI();
mapView.onCreate(savedInstanceState);
fusedLocationMethod(savedInstanceState);
getLocationPermission();
//getLastLocation();
}
private void bindUI() {
mapView = findViewById(R.id.map_view);
tvCoordinates = findViewById(R.id.tv_coordinates);
}
public void fusedLocationMethod(Bundle savedInstanceState) {
mFusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
}
private void getLocationPermission() {
if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(this,
new String[]{android.Manifest.permission.ACCESS_FINE_LOCATION, android.Manifest.permission.ACCESS_COARSE_LOCATION},
LOCATION_PERMISSION_CONSTANT);
return;
}
getLastLocation();
}
@Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case LOCATION_PERMISSION_CONSTANT:
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
if (googleApiClient == null) {
getLocationPermission();
} else {
getLocationPermission();
}
} else {
Toast.makeText(this, "Permission Denied", Toast.LENGTH_SHORT).show();
}
break;
}
}
public void getLastLocation() {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
mFusedLocationClient.getLastLocation()
.addOnSuccessListener(this, new OnSuccessListener<Location>() {
@Override
public void onSuccess(Location location) {
if (location == null) {
Log.w(TAG, "onSuccess:null");
return;
}
mLastLocation = location;
preLat = location.getLatitude();
preLong = location.getLongitude();
settingMap(location.getLatitude(), location.getLongitude());
try {
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
} catch (Exception e) {
e.printStackTrace();
Log.d("Error", e.getMessage() + " 203");
}
if (ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
}
})
.addOnFailureListener(this, new OnFailureListener() {
@Override
public void onFailure(@NonNull Exception e) {
Log.w(TAG, "getLastLocation:onFailure", e);
}
});
}
private double preLat = 0.0;
private double preLong = 0.0;
//setting map
private void settingMap(final double lat, final double longi) {
mapView.getMapAsync(new OnMapReadyCallback() {
@Override
public void onMapReady(GoogleMap gglmap) {
googleMap = gglmap;
googleMap.getUiSettings().setAllGesturesEnabled(false);
googleMap.clear();
CameraPosition cameraPosition = new CameraPosition.Builder().target(new LatLng(lat, longi)).zoom(16).build();
googleMap.moveCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));
googleMap.getUiSettings().setMyLocationButtonEnabled(false);
//permission for location
if (ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
googleMap.setMyLocationEnabled(true);
//googleMap.getUiSettings().setAllGesturesEnabled(false);
googleMap.setOnCameraIdleListener(new GoogleMap.OnCameraIdleListener() {
@Override
public void onCameraIdle() {
int mapViewHeight = mapView.getHeight();
int mapViewWidth = mapView.getWidth();
Projection projection = googleMap.getProjection();
LatLng geographicalPosition = projection.fromScreenLocation(new Point(mapViewWidth / 2, mapViewHeight / 2));
// Toast.makeText(getActivity(),""+geographicalPosition.latitude+" , "+geographicalPosition.longitude,Toast.LENGTH_LONG).show();
tvCoordinates.setText(geographicalPosition.latitude + " , " + geographicalPosition.longitude);
}
});
}
});
}
@Override
public void onResume() {
super.onResume();
mapView.onResume();
}
@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
super.onSaveInstanceState(savedInstanceState);
mapView.onSaveInstanceState(savedInstanceState);
}
@Override
public void onPause() {
super.onPause();
mapView.onPause();
}
@Override
public void onStop() {
super.onStop();
mapView.onStop();
}
@Override
public void onLowMemory() {
super.onLowMemory();
mapView.onLowMemory();
}
@Override
public void onDestroy() {
super.onDestroy();
mapView.onDestroy();
}
@Override
public void onStart() {
super.onStart();
mapView.onStart();
}
}
EnhancedMapView.java
public class EnhanchedMapView extends MapView implements OnMapReadyCallback {
private long mLastTouchTime = -1;
private static final int INVALID_POINTER_ID = -1;
private OnMapReadyCallback mMapReadyCallback;
private GoogleMap mGoogleMap;
private float mPosX;
private float mPosY;
private float mLastTouchX;
private float mLastTouchY;
private int mActivePointerId = INVALID_POINTER_ID;
private void init() {
}
@Override
public void getMapAsync(OnMapReadyCallback callback) {
mMapReadyCallback = callback;
super.getMapAsync(this);
}
@Override
public void onMapReady(GoogleMap googleMap) {
mGoogleMap = googleMap;
}
LatLng geographicalPosition;
boolean isPinch = false;
@Override
public boolean dispatchTouchEvent(MotionEvent event) {
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
mGoogleMap.getUiSettings().setScrollGesturesEnabled(true);
long thisTime = System.currentTimeMillis();
if (thisTime - mLastTouchTime < ViewConfiguration.getDoubleTapTimeout()) {
if (mGoogleMap != null) {
LatLng zoomCenter = mGoogleMap.getProjection().fromScreenLocation(new Point((int) event.getX(), (int) event.getY()));
float currentZoom = mGoogleMap.getCameraPosition().zoom;
int mapViewHeight = getHeight();
int mapViewWidth = getWidth();
Projection projection = mGoogleMap.getProjection();
geographicalPosition = projection.fromScreenLocation(new Point(mapViewWidth / 2, mapViewHeight / 2));
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(geographicalPosition);
mGoogleMap.addMarker(markerOptions);
mGoogleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(geographicalPosition.latitude, geographicalPosition.longitude), currentZoom + 1));
}
mLastTouchTime = -1;
} else {
mLastTouchTime = thisTime;
mGoogleMap.getUiSettings().setZoomGesturesEnabled(false);
}
break;
case MotionEvent.ACTION_POINTER_DOWN:
mGoogleMap.getUiSettings().setZoomGesturesEnabled(false);
mGoogleMap.getUiSettings().setScrollGesturesEnabled(false);
Log.d("Nirmal", "ACTION_POINTER_DOWN");
isPinch = true;
int mapViewHeight = getHeight();
int mapViewWidth = getWidth();
Projection projection = mGoogleMap.getProjection();
geographicalPosition = projection.fromScreenLocation(new Point(mapViewWidth / 2, mapViewHeight / 2));
break;
case MotionEvent.ACTION_POINTER_UP:
mGoogleMap.getUiSettings().setScrollGesturesEnabled(true);
isPinch = false;
break;
case MotionEvent.ACTION_UP:
mGoogleMap.getUiSettings().setScrollGesturesEnabled(true);
break;
case MotionEvent.ACTION_MOVE:
if (isPinch) {
if (mGoogleMap == null || geographicalPosition == null)
break;
//Log.d("Nirmal", "ACTION_MOVE");
Log.d("Nirmal", "" + event.getX() + " , " + event.getY());
float currentZoom = mGoogleMap.getCameraPosition().zoom;
mGoogleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(geographicalPosition.latitude, geographicalPosition.longitude), currentZoom + 0.05f));
}
break;
}
return super.dispatchTouchEvent(event);
}
}
解决方案
As pskink recommended, you need ScaleGestureDetector object, which determines zoom "direction". Something like that:
ScaleGestureDetector mScaleDetector = new ScaleGestureDetector(getContext(),
new ScaleGestureDetector.SimpleOnScaleGestureListener() {
private float scaleFactor = 1f;
@Override
public boolean onScale(ScaleGestureDetector detector) {
// store scale factor for detect zoom "direction" on end
scaleFactor = detector.getScaleFactor();
return true;
}
@Override
public void onScaleEnd(ScaleGestureDetector detector) {
float currentZoom = mGoogleMap.getCameraPosition().zoom;
if (scaleFactor > 1) {
// zoom in detected
mGoogleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(mZoomCenter, currentZoom + 1));
} else if (scaleFactor < 1) {
// zoom out detected
mGoogleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(mZoomCenter, currentZoom - 1));
}
super.onScaleEnd(detector);
}
});
And you can use it in your EnhanchedMapView.dispatchTouchEvent() easily:
...
@Override
public boolean dispatchTouchEvent(MotionEvent event) {
// just call .onTouchEvent() on your ScaleGestureDetector object
mScaleDetector.onTouchEvent(event);
switch (event.getAction() & MotionEvent.ACTION_MASK) {
...
NB! You need to disable GoogleMap zoom gesture
@Override
public void onMapReady(GoogleMap googleMap) {
mGoogleMap = googleMap;
mGoogleMap.getUiSettings().setZoomGesturesEnabled(false);
...
}
and never enable it.
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