Compass click rotates around focal point (if available) (#7977)

* add set bearing method taking focal point into account

* notify CompassView when FocalPoint changes

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/MapView.java

@@ -127,7 +127,7 @@ public class MapView extends FrameLayout {
     nativeMapView = new NativeMapView(this);
 
     // callback for focal point invalidation
-    FocalPointInvalidator focalPoint = new FocalPointInvalidator();
+    FocalPointInvalidator focalPoint = new FocalPointInvalidator(compassView);
 
     // callback for registering touch listeners
     RegisterTouchListener registerTouchListener = new RegisterTouchListener();
@@ -944,9 +944,18 @@ public class MapView extends FrameLayout {
 
   private class FocalPointInvalidator implements FocalPointChangeListener {
 
+    private final FocalPointChangeListener[] focalPointChangeListeners;
+
+    FocalPointInvalidator(FocalPointChangeListener... listeners) {
+      focalPointChangeListeners = listeners;
+    }
+
     @Override
     public void onFocalPointChanged(PointF pointF) {
       mapGestureDetector.setFocalPoint(pointF);
+      for (FocalPointChangeListener focalPointChangeListener : focalPointChangeListeners) {
+        focalPointChangeListener.onFocalPointChanged(pointF);
+      }
     }
   }
 

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/MapboxMap.java

@@ -738,6 +738,21 @@ public final class MapboxMap {
     transform.resetNorth();
   }
 
+  /**
+   * Set focal bearing.
+   */
+  public void setFocalBearing(double bearing, float focalX, float focalY, long duration) {
+    transform.setBearing(bearing, focalX, focalY, duration);
+  }
+
+  public float getHeight() {
+    return nativeMapView.getHeight();
+  }
+
+  public float getWidth() {
+    return nativeMapView.getWidth();
+  }
+
   //
   // Debug
   //

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/NativeMapView.java

@@ -530,6 +530,13 @@ final class NativeMapView {
     nativeSetBearingXY(nativeMapViewPtr, degrees, cx / pixelRatio, cy / pixelRatio);
   }
 
+  public void setBearing(double degrees, double fx, double fy, long duration) {
+    if (isDestroyedOn("setBearing")) {
+      return;
+    }
+    nativeSetFocalBearing(nativeMapViewPtr, degrees, fx / pixelRatio, fy / pixelRatio, duration);
+  }
+
   public double getBearing() {
     if (isDestroyedOn("getBearing")) {
       return 0;
@@ -1047,6 +1054,9 @@ final class NativeMapView {
   private native void nativeSetBearingXY(long nativeMapViewPtr, double degrees,
                                          double cx, double cy);
 
+  private native void nativeSetFocalBearing(long nativeMapViewPtr, double degrees,
+                                            double fx, double fy, long duration);
+
   private native double nativeGetBearing(long nativeMapViewPtr);
 
   private native void nativeResetNorth(long nativeMapViewPtr);

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/Transform.java

@@ -220,6 +220,13 @@ final class Transform implements MapView.OnMapChangedListener {
     mapView.setBearing(bearing, focalX, focalY);
   }
 
+  void setBearing(double bearing, float focalX, float focalY, long duration) {
+    if (myLocationView != null) {
+      myLocationView.setBearing(bearing);
+    }
+    mapView.setBearing(bearing, focalX, focalY, duration);
+  }
+
 
   //
   // LatLng / CenterCoordinate

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/widgets/CompassView.java

@@ -1,17 +1,20 @@
 package com.mapbox.mapboxsdk.maps.widgets;
 
 import android.content.Context;
+import android.graphics.PointF;
 import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
 import android.support.v4.content.ContextCompat;
 import android.support.v4.view.ViewCompat;
 import android.support.v4.view.ViewPropertyAnimatorCompat;
 import android.support.v4.view.ViewPropertyAnimatorListenerAdapter;
+import android.support.v7.widget.AppCompatImageView;
 import android.util.AttributeSet;
 import android.view.View;
 import android.view.ViewGroup;
-import android.widget.ImageView;
 
 import com.mapbox.mapboxsdk.R;
+import com.mapbox.mapboxsdk.maps.FocalPointChangeListener;
 import com.mapbox.mapboxsdk.maps.MapboxMap;
 
 import java.lang.ref.WeakReference;
@@ -25,7 +28,7 @@ import java.lang.ref.WeakReference;
  * use {@link com.mapbox.mapboxsdk.maps.UiSettings}.
  * </p>
  */
-public final class CompassView extends ImageView implements Runnable {
+public final class CompassView extends AppCompatImageView implements Runnable, FocalPointChangeListener {
 
   private static final long TIME_WAIT_IDLE = 500;
   private static final long TIME_FADE_ANIMATION = TIME_WAIT_IDLE;
@@ -34,6 +37,7 @@ public final class CompassView extends ImageView implements Runnable {
   private double direction = 0.0;
   private boolean fadeCompassViewFacingNorth = true;
   private ViewPropertyAnimatorCompat fadeAnimator;
+  private PointF focalPoint;
 
   public CompassView(Context context) {
     super(context);
@@ -96,6 +100,11 @@ public final class CompassView extends ImageView implements Runnable {
     }
   }
 
+  @Nullable
+  PointF getFocalPoint() {
+    return focalPoint;
+  }
+
   public void update(final double direction) {
     this.direction = direction;
 
@@ -143,6 +152,11 @@ public final class CompassView extends ImageView implements Runnable {
     }
   }
 
+  @Override
+  public void onFocalPointChanged(PointF pointF) {
+    focalPoint = pointF;
+  }
+
   static class CompassClickListener implements View.OnClickListener {
 
     private WeakReference<MapboxMap> mapboxMap;
@@ -158,7 +172,12 @@ public final class CompassView extends ImageView implements Runnable {
       final MapboxMap mapboxMap = this.mapboxMap.get();
       final CompassView compassView = this.compassView.get();
       if (mapboxMap != null && compassView != null) {
-        mapboxMap.resetNorth();
+        PointF focalPoint = compassView.getFocalPoint();
+        if (focalPoint != null) {
+          mapboxMap.setFocalBearing(0, focalPoint.x, focalPoint.y, TIME_MAP_NORTH_ANIMATION);
+        } else {
+          mapboxMap.setFocalBearing(0, mapboxMap.getWidth() / 2, mapboxMap.getHeight() / 2, TIME_MAP_NORTH_ANIMATION);
+        }
         compassView.postDelayed(compassView, TIME_WAIT_IDLE + TIME_MAP_NORTH_ANIMATION);
       }
     }

platform/android/src/jni.cpp

@@ -618,6 +618,14 @@ void nativeSetBearing(JNIEnv *env, jni::jobject* obj, jlong nativeMapViewPtr, jd
     nativeMapView->getMap().setBearing(degrees, duration);
 }
 
+void nativeSetFocalBearing(JNIEnv *env, jni::jobject* obj, jlong nativeMapViewPtr, jdouble degrees, jdouble fx,
+                           jdouble fy, jlong milliseconds) {
+    assert(nativeMapViewPtr != 0);
+    NativeMapView *nativeMapView = reinterpret_cast<NativeMapView *>(nativeMapViewPtr);
+    mbgl::ScreenCoordinate center(fx, fy);
+    nativeMapView->getMap().setBearing(degrees, center, mbgl::Milliseconds(milliseconds));
+}
+
 void nativeSetBearingXY(JNIEnv *env, jni::jobject* obj, jlong nativeMapViewPtr, jdouble degrees,
                               jdouble cx, jdouble cy) {
     assert(nativeMapViewPtr != 0);
@@ -1894,6 +1902,7 @@ void registerNatives(JavaVM *vm) {
         MAKE_NATIVE_METHOD(nativeSetMaxZoom, "(JD)V"),
         MAKE_NATIVE_METHOD(nativeRotateBy, "(JDDDDJ)V"),
         MAKE_NATIVE_METHOD(nativeSetBearing, "(JDJ)V"),
+        MAKE_NATIVE_METHOD(nativeSetFocalBearing, "(JDDDJ)V"),
         MAKE_NATIVE_METHOD(nativeSetBearingXY, "(JDDD)V"),
         MAKE_NATIVE_METHOD(nativeGetBearing, "(J)D"),
         MAKE_NATIVE_METHOD(nativeResetNorth, "(J)V"),