在Google Map Android上将“我的位置”按钮左对齐

Question

I have been trying to left align My Location button on google map as its aligned right by default.

I've seen solution code here , but isn't helped much.

And tried the code following:

SupportMapFragment mapFragment = ((SupportMapFragment)
getChildFragmentManager().findFragmentById(R.id.fragmentMap));
View myLocationButton = mapFragment.getView().findViewById(0x2);

if (myLocationButton != null && myLocationButton.getLayoutParams() instanceof RelativeLayout.LayoutParams) {
    // location button is inside of RelativeLayout
    RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams) myLocationButton.getLayoutParams();
    params.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM);
    params.addRule(RelativeLayout.ALIGN_PARENT_LEFT);
    params.addRule(RelativeLayout.ALIGN_PARENT_RIGHT, 0);
    params.addRule(RelativeLayout.ALIGN_PARENT_TOP, 0);
    // Update margins, set to 10dp
    final int margin = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 10, getResources().getDisplayMetrics());
    params.setMargins(margin, margin, margin, margin);
    myLocationButton.setLayoutParams(params);
}

Answer 1

You should do that in parent.post() method. Try this code:

void myLocationBottomLeftAlign() {
    try {
        mGoogleMap.setMyLocationEnabled(true);
        mGoogleMap.getUiSettings().setMyLocationButtonEnabled(true);
        mGoogleMap.getUiSettings().setZoomControlsEnabled(true);

        final ViewGroup parent = (ViewGroup) mMapFragment.getView().findViewWithTag("GoogleMapMyLocationButton").getParent();
        parent.post(new Runnable() {
            @Override
            public void run() {
                try {
                    Resources r = getResources();
                    int marginPixels = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 20, r.getDisplayMetrics());

                    View mapLocation = mMapFragment.getView().findViewWithTag("GoogleMapMyLocationButton");

                    // create layoutParams, giving it our wanted width and height(important, by default the width is "match parent")
                    RelativeLayout.LayoutParams rlp = new RelativeLayout.LayoutParams(mapLocation.getHeight(),
                            mapLocation.getHeight());
                    // position on top right
                    rlp.addRule(RelativeLayout.ALIGN_PARENT_LEFT);
                    rlp.addRule(RelativeLayout.ALIGN_PARENT_RIGHT, 0);
                    rlp.addRule(RelativeLayout.ALIGN_PARENT_TOP, 0);
                    rlp.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM);
                    //give compass margin
                    rlp.setMargins(marginPixels, marginPixels, marginPixels, marginPixels);
                    mapLocation.setLayoutParams(rlp);

                } catch (Exception ex) {
                    ex.printStackTrace();
                }
            }
        });
    } catch (Exception ex) {
        ex.printStackTrace();
    }
}

call it in onMapReady() and don't forget about location permission:

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

    if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        int locationPermission = ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION);
        if (locationPermission == PackageManager.PERMISSION_GRANTED) {
            myLocationBottomLeftAlign();
        } else {
            // request permission and than call myLocationBottomLeftAlign();

        }
    } else {
        myLocationBottomLeftAlign();
    }
}