Wie zeichnet die Zomato App freie Hand über Karten in Android?

Question

Demo ist hier: - https://www.youtube.com/watch?v=a-xV6rFYT_0

Ich möchte das gleiche tun, aber wie macht es das? ist es Overlay..if ja dann, wie verfolgen sie innerhalb des Kreises?

Answer 1

Es ist einfach, von Ihnen zu erreichen, setzen eine View über die Karte und verwalten die MotionEvent s:

activity_maps.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent"> 

    <fragment 
     android:id="@+id/map" 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     android:name="com.google.android.gms.maps.SupportMapFragment" /> 

    <View 
     android:id="@+id/draggable" 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     android:clickable="true" /> 

</RelativeLayout> 

MapsActivity.java

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback { 
    private GoogleMap mMap; 
    private View draggableView; 
    private List<LatLng> polylinePoints = new ArrayList<>(); 
    private Polyline polyline; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_maps); 

     ((SupportMapFragment) getSupportFragmentManager() 
       .findFragmentById(R.id.map)).getMapAsync(this); 

     draggableView = findViewById(R.id.draggable); 
    } 

    @Override 
    public void onMapReady(GoogleMap googleMap) { 
     mMap = googleMap; 

     draggableView.setOnTouchListener(new View.OnTouchListener() { 
      @Override 
      public boolean onTouch(View view, MotionEvent motionEvent) { 
       LatLng position = mMap.getProjection().fromScreenLocation(
         new Point((int) motionEvent.getX(), (int) motionEvent.getY())); 

       if (motionEvent.getAction() == MotionEvent.ACTION_DOWN) { 
        if (polyline != null) { 
         polyline.remove(); 
         polyline = null; 

         polylinePoints.clear(); 
        } 
        polylinePoints.add(position); 
        polyline = mMap.addPolyline(new PolylineOptions().addAll(polylinePoints)); 
       } else if (motionEvent.getAction() == MotionEvent.ACTION_MOVE){ 
        polylinePoints.add(position); 
        polyline.setPoints(polylinePoints); 
       } else if (motionEvent.getAction() == MotionEvent.ACTION_UP) { 
        // Close the polyline? 
        // Send the polyline to make a search? 
       } 
       return true; 
      } 
     }); 
    } 
}