时间戳

首页 > 解决方案 > 如何从谷歌地图标记中获取视图？

android - 如何从谷歌地图标记中获取视图？

问题描述

我想将showcaseview添加到android地图上的标记！？展示库以视图为论据。如何从标记中获取视图？

我正在尝试这段代码

new GuideView.Builder(this)
    .setTitle("Guide Title Text")
    .setContentText("Guide Description Text\n .....Guide Description Text\n .....Guide Description Text .....")
    .setGravity(Gravity.auto) //optional
    .setDismissType(DismissType.anywhere) //optional - default DismissType.targetView
    .setTargetView(view)
    .setContentTextSize(12)//optional
    .setTitleTextSize(14)//optional
    .build()
    .show();

它将视图作为 setTargetView 中的参数，而不是标记对象

这是我想使用的图书馆 https://github.com/mreram/ShowCaseView

标签： androidandroid-studiogoogle-mapsgoogle-maps-markersgoogle-maps-android-api-2

解决方案

Marker不是视图，您无法从中获得View。但无论如何，您可以创建虚拟透明View并将其以编程方式放置在选定的标记上，然后通过setTargetView方法将其传递给 ShowCaseView 库。因此，您需要围绕MapFragmentor的根视图MapView，例如RelativeLayout( activity_main.xml)：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/mapview_root"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="<YOUR_PACKAGE_NAME>.MainActivity">

    <com.google.android.gms.maps.MapView android:id="@+id/mapview"
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        />

</RelativeLayout>

和虚拟透明视图布局（transparent_layout.xml）：

<?xml version="1.0" encoding="utf-8"?>
<View
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="20dp"  <- adjust size programmatically or set to default size of Marker
    android:layout_height="30dp"
    android:layout_centerInParent="true"
    android:background="@android:color/transparent">
</View>

Than, in eg MainActivity, you need get root layout and inflate dummy transparent view, and when marker selected (eg on click) you should get current screen coordinates of the selected Markerand place dummy transparent view exactly over it. 因为RelativeLayout它可以通过setLeft()for x-coordinate 和setTop()for y-coordinate 来完成（当然你需要根据Marker锚点调整偏移量）。像这样的东西：

public class MainActivity extends AppCompatActivity {

    private static final String MAP_VIEW_BUNDLE_KEY = "MapViewBundleKey";
    static final LatLng KYIV = new LatLng(50.450311, 30.523730);

    private GoogleMap mGoogleMap;
    private RelativeLayout mMapViewRoot;
    private MapView mGoogleMapView;

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

        Bundle mapViewBundle = null;
        if (savedInstanceState != null) {
            mapViewBundle = savedInstanceState.getBundle(MAP_VIEW_BUNDLE_KEY);
        }

        mMapViewRoot = (RelativeLayout) findViewById(R.id.mapview_root);
        // dummy transparent view
        final View transparentView = View.inflate(getApplicationContext(), R.layout.transparent_view, mMapViewRoot);

        mGoogleMapView = (MapView) findViewById(R.id.mapview);
        mGoogleMapView.onCreate(mapViewBundle);
        mGoogleMapView.getMapAsync(new OnMapReadyCallback() {
            @Override
            public void onMapReady(GoogleMap googleMap) {
                mGoogleMap = googleMap;
                mGoogleMap.addMarker(new MarkerOptions().position(KYIV).title("Kyiv"));
                mGoogleMap.setOnMarkerClickListener(new GoogleMap.OnMarkerClickListener() {
                    @Override
                    public boolean onMarkerClick(Marker marker) {
                        // get screen coordinates of the marker
                        Projection projection = mGoogleMap.getProjection();
                        Point viewPosition = projection.toScreenLocation(marker.getPosition());

                        // place dummy transparent view over the marker
                        transparentView.setLeft(viewPosition.x);
                        transparentView.setTop(viewPosition.y);
                        return false;
                    }
                });

                mGoogleMap.animateCamera(CameraUpdateFactory.newLatLng(KYIV));

                ...

            }
        });

    }
...

当然这只是一个想法的例子，你应该改进标记大小、锚点等的代码。

推荐阅读