So

我需要使用addOnGlobalLayoutListener来获得适当的示例

例如，你的谷歌地图在RelativeLayout中:

RelativeLayout mapLayout = (RelativeLayout)findViewById(R.id.map_layout);
mapLayout.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
        @Override
        public void onGlobalLayout() {
            //and write code, which you can see in answer above
        }
    });

使用“getCenterCoordinate”方法获取中心坐标，并在camerposition中使用。

private void setUpMap() {
    mMap.setMyLocationEnabled(true);
    mMap.getUiSettings().setScrollGesturesEnabled(true);
    mMap.getUiSettings().setTiltGesturesEnabled(true);
    mMap.getUiSettings().setRotateGesturesEnabled(true);

    clientMarker = mMap.addMarker(new MarkerOptions()
            .position(new LatLng(Double.valueOf(-12.1024174), Double.valueOf(-77.0262274)))
            .icon(BitmapDescriptorFactory.fromResource(R.mipmap.ic_taxi))
    );
    clientMarker = mMap.addMarker(new MarkerOptions()
            .position(new LatLng(Double.valueOf(-12.1024637), Double.valueOf(-77.0242617)))
            .icon(BitmapDescriptorFactory.fromResource(R.mipmap.ic_location))
    );

    camPos = new CameraPosition.Builder()
            .target(getCenterCoordinate())
            .zoom(17)
            .build();
    camUpd3 = CameraUpdateFactory.newCameraPosition(camPos);
    mMap.animateCamera(camUpd3);
}


public LatLng getCenterCoordinate(){
    LatLngBounds.Builder builder = new LatLngBounds.Builder();
    builder.include(new LatLng(Double.valueOf(-12.1024174), Double.valueOf(-77.0262274)));
    builder.include(new LatLng(Double.valueOf(-12.1024637), Double.valueOf(-77.0242617)));
    LatLngBounds bounds = builder.build();
    return bounds.getCenter();
}

我有另一种方法来做同样的事情，效果很好。为了在屏幕上显示所有标记，我们需要一个中长和缩放级别。这里是一个函数，它会给你两个，需要所有标记的Latlng对象作为输入。

 public Pair<LatLng, Integer> getCenterWithZoomLevel(LatLng... l) {
    float max = 0;

    if (l == null || l.length == 0) {
        return null;
    }
    LatLngBounds.Builder b = new LatLngBounds.Builder();
    for (int count = 0; count < l.length; count++) {
        if (l[count] == null) {
            continue;
        }
        b.include(l[count]);
    }

    LatLng center = b.build().getCenter();

    float distance = 0;
    for (int count = 0; count < l.length; count++) {
        if (l[count] == null) {
            continue;
        }
        distance = distance(center, l[count]);
        if (distance > max) {
            max = distance;
        }
    }

    double scale = max / 1000;
    int zoom = ((int) (16 - Math.log(scale) / Math.log(2)));
    return new Pair<LatLng, Integer>(center, zoom);
}

这个函数返回Pair对象，你可以像这样使用它

getCenterWithZoomLevel(l1,l2,l3..); mGoogleMap.moveCamera (CameraUpdateFactory.newLatLngZoom(一对。首先,pair.second));

你可以不用填充来让标记远离屏幕边界，你可以通过-1来调整缩放。

谷歌地图V2

以下解决方案适用于Android棉花糖6 (API 23, API 24, API 25, API 26, API 27, API 28)。它也适用于Xamarin。

LatLngBounds.Builder builder = new LatLngBounds.Builder();

//the include method will calculate the min and max bound.
builder.include(marker1.getPosition());
builder.include(marker2.getPosition());
builder.include(marker3.getPosition());
builder.include(marker4.getPosition());

LatLngBounds bounds = builder.build();

int width = getResources().getDisplayMetrics().widthPixels;
int height = getResources().getDisplayMetrics().heightPixels;
int padding = (int) (width * 0.10); // offset from edges of the map 10% of screen

CameraUpdate cu = CameraUpdateFactory.newLatLngBounds(bounds, width, height, padding);

mMap.animateCamera(cu);

我不能使用onGlobalLayoutlistener，所以这里有另一个解决方案来防止 “地图大小不能为0。最有可能的是，地图视图的布局还没有发生。要么等待布局发生，要么使用newLatLngBounds(LatLngBounds, int, int, int)，它允许你指定地图的尺寸。

mMap.setOnMapLoadedCallback(new GoogleMap.OnMapLoadedCallback() { 
@Override 
public void onMapLoaded() { 
    mMap.moveCamera(CameraUpdateFactory.newLatLngBounds(builder.build(), 15));
 } 
});

对我来说很好。

从这段代码中，我在地图屏幕上显示特定缩放的多个标记。

//声明变量

private LatLngBounds bounds;
private LatLngBounds.Builder builder;

//添加多个标记点的方法

private void drawMarker(LatLng point, String text) {

        MarkerOptions markerOptions = new MarkerOptions();
        markerOptions.position(point).title(text).icon(BitmapDescriptorFactory.fromResource(R.drawable.icon));
        mMap.addMarker(markerOptions);
        builder.include(markerOptions.getPosition());

    }

//用于在地图上添加多个可见标记

@Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;
        builder = new LatLngBounds.Builder();
    for (int i = 0; i < locationList.size(); i++) {

        drawMarker(new LatLng(Double.parseDouble(locationList.get(i).getLatitude()), Double.parseDouble(locationList.get(i).getLongitude())), locationList.get(i).getNo());

     }
     bounds = builder.build();
     CameraUpdate cu = CameraUpdateFactory.newLatLngBounds(bounds, 0);
     mMap.animateCamera(cu);