Question

我正在开发一个Android应用程序，我正在使用Google Map API v2。我需要在地图上显示带有自定义标记的用户位置。

每个标记都会从URL显示用户的图片。必须从服务器以异步模式下载映像。有关示例，请参阅随附的屏幕截图。

如何在标记中添加图像和自定义信息？

enter image description here

Answer 1

在Google Maps API v2 Demo中有一个MarkerDemoActivity课程，您可以在其中查看如何将自定义图像设置为Google地图。

// Uses a custom icon.
mSydney = mMap.addMarker(new MarkerOptions()
    .position(SYDNEY)
    .title("Sydney")
    .snippet("Population: 4,627,300")
    .icon(BitmapDescriptorFactory.fromResource(R.drawable.arrow)));

由于这只是用图像替换标记，您可能希望使用Canvas来绘制更复杂和更漂亮的东西：

Bitmap.Config conf = Bitmap.Config.ARGB_8888;
Bitmap bmp = Bitmap.createBitmap(80, 80, conf);
Canvas canvas1 = new Canvas(bmp);

// paint defines the text color, stroke width and size
Paint color = new Paint();
color.setTextSize(35);
color.setColor(Color.BLACK);

// modify canvas
canvas1.drawBitmap(BitmapFactory.decodeResource(getResources(),
    R.drawable.user_picture_image), 0,0, color);
canvas1.drawText("User Name!", 30, 40, color);

// add marker to Map
mMap.addMarker(new MarkerOptions()
    .position(USER_POSITION)
    .icon(BitmapDescriptorFactory.fromBitmap(bmp))
    // Specifies the anchor to be at a particular point in the marker image.
    .anchor(0.5f, 1));

这会将画布canvas1绘制到GoogleMap mMap上。代码应该（大部分）说明一下，有很多教程如何绘制Canvas。您可以从Android Developer页面查看Canvas and Drawables开始。

现在您还想从网址下载图片。

URL url = new URL(user_image_url);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();   
conn.setDoInput(true);   
conn.connect();     
InputStream is = conn.getInputStream();
bmImg = BitmapFactory.decodeStream(is);

您必须从后台线程下载图片（您可以使用AsyncTask或Volley或RxJava。

之后，您可以将BitmapFactory.decodeResource(getResources(), R.drawable.user_picture_image)替换为下载的图片bmImg。

Answer 2

我还使用的另一种更简单的解决方案是创建自定义标记布局并将其转换为位图。

view_custom_marker.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/custom_marker_view"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:background="@drawable/marker_mask">

    <ImageView
        android:id="@+id/profile_image"
        android:layout_width="48dp"
        android:layout_height="48dp"
        android:layout_gravity="center_horizontal"
        android:contentDescription="@null"
        android:src="@drawable/avatar" />
</FrameLayout>

使用下面的代码将此视图转换为位图

 private Bitmap getMarkerBitmapFromView(@DrawableRes int resId) {

        View customMarkerView = ((LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE)).inflate(R.layout.view_custom_marker, null);
        ImageView markerImageView = (ImageView) customMarkerView.findViewById(R.id.profile_image);
        markerImageView.setImageResource(resId);
        customMarkerView.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED);
        customMarkerView.layout(0, 0, customMarkerView.getMeasuredWidth(), customMarkerView.getMeasuredHeight());
        customMarkerView.buildDrawingCache();
        Bitmap returnedBitmap = Bitmap.createBitmap(customMarkerView.getMeasuredWidth(), customMarkerView.getMeasuredHeight(),
                Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(returnedBitmap);
        canvas.drawColor(Color.WHITE, PorterDuff.Mode.SRC_IN);
        Drawable drawable = customMarkerView.getBackground();
        if (drawable != null)
            drawable.draw(canvas);
        customMarkerView.draw(canvas);
        return returnedBitmap;
    }

在Map ready回调中添加自定义标记。

@Override
public void onMapReady(GoogleMap googleMap) {
    Log.d(TAG, "onMapReady() called with");
    mGoogleMap = googleMap;
    MapsInitializer.initialize(this);
    addCustomMarker();
}
private void addCustomMarker() {
    Log.d(TAG, "addCustomMarker()");
    if (mGoogleMap == null) {
        return;
    }

    // adding a marker on map with image from  drawable
   mGoogleMap.addMarker(new MarkerOptions()
            .position(mDummyLatLng)
            .icon(BitmapDescriptorFactory.fromBitmap(getMarkerBitmapFromView(R.drawable.avatar))));
}

有关详情，请点击以下链接

How to create custom marker using layout?

Answer 3

我希望分享我的解决方案还为时不晚。在此之前，您可以按照Android Developer documentation中的说明进行操作。要实现此目的，您需要将Cluster Manager与ClusterItem一起使用。

创建一个实现public class SampleJob implements ClusterItem { private double latitude; private double longitude; //Create constructor, getter and setter here @Override public LatLng getPosition() { return new LatLng(latitude, longitude); }

的对象

public class JobRenderer extends DefaultClusterRenderer< SampleJob > {

private final IconGenerator iconGenerator;
private final IconGenerator clusterIconGenerator;
private final ImageView imageView;
private final ImageView clusterImageView;
private final int markerWidth;
private final int markerHeight;
private final String TAG = "ClusterRenderer";
private DisplayImageOptions options;


public JobRenderer(Context context, GoogleMap map, ClusterManager<SampleJob> clusterManager) {
    super(context, map, clusterManager);

    // initialize cluster icon generator
    clusterIconGenerator = new IconGenerator(context.getApplicationContext());
    View clusterView = LayoutInflater.from(context).inflate(R.layout.multi_profile, null);
    clusterIconGenerator.setContentView(clusterView);
    clusterImageView = (ImageView) clusterView.findViewById(R.id.image);

    // initialize cluster item icon generator
    iconGenerator = new IconGenerator(context.getApplicationContext());
    imageView = new ImageView(context.getApplicationContext());
    markerWidth = (int) context.getResources().getDimension(R.dimen.custom_profile_image);
    markerHeight = (int) context.getResources().getDimension(R.dimen.custom_profile_image);
    imageView.setLayoutParams(new ViewGroup.LayoutParams(markerWidth, markerHeight));
    int padding = (int) context.getResources().getDimension(R.dimen.custom_profile_padding);
    imageView.setPadding(padding, padding, padding, padding);
    iconGenerator.setContentView(imageView);

    options = new DisplayImageOptions.Builder()
            .showImageOnLoading(R.drawable.circle_icon_logo)
            .showImageForEmptyUri(R.drawable.circle_icon_logo)
            .showImageOnFail(R.drawable.circle_icon_logo)
            .cacheInMemory(false)
            .cacheOnDisk(true)
            .considerExifParams(true)
            .bitmapConfig(Bitmap.Config.RGB_565)
            .build();
}

@Override
protected void onBeforeClusterItemRendered(SampleJob job, MarkerOptions markerOptions) {


    ImageLoader.getInstance().displayImage(job.getJobImageURL(), imageView, options);
    Bitmap icon = iconGenerator.makeIcon(job.getName());
    markerOptions.icon(BitmapDescriptorFactory.fromBitmap(icon)).title(job.getName());


}

@Override
protected void onBeforeClusterRendered(Cluster<SampleJob> cluster, MarkerOptions markerOptions) {

    Iterator<Job> iterator = cluster.getItems().iterator();
    ImageLoader.getInstance().displayImage(iterator.next().getJobImageURL(), clusterImageView, options);
    Bitmap icon = clusterIconGenerator.makeIcon(iterator.next().getName());
    markerOptions.icon(BitmapDescriptorFactory.fromBitmap(icon));
}

@Override
protected boolean shouldRenderAsCluster(Cluster cluster) {
    return cluster.getSize() > 1;
}

创建默认渲染器类。这是完成所有工作的类（使用您自己的样式扩展自定义标记/集群）。我正在使用通用图像加载器来下载和缓存图像。

public class SampleActivity extends AppCompatActivity implements OnMapReadyCallback {

private ClusterManager<SampleJob> mClusterManager;
private GoogleMap mMap;
private ArrayList<SampleJob> jobs = new ArrayList<SampleJob>();

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

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


@Override
public void onMapReady(GoogleMap googleMap) {
    mMap = googleMap;
    mMap.getUiSettings().setMapToolbarEnabled(true);
    mClusterManager = new ClusterManager<SampleJob>(this, mMap);
    mClusterManager.setRenderer(new JobRenderer(this, mMap, mClusterManager));
    mMap.setOnCameraChangeListener(mClusterManager);
    mMap.setOnMarkerClickListener(mClusterManager);

    //Assume that we already have arraylist of jobs


    for(final SampleJob job: jobs){
        mClusterManager.addItem(job);
    }
    mClusterManager.cluster();
}

在您的activity / fragment类中应用集群管理器。
```
$rootScope
```
结果

Answer 4

从lambda回答来看，我已经接近了要求。

boolean imageCreated = false;

Bitmap bmp = null;
Marker currentLocationMarker;
private void doSomeCustomizationForMarker(LatLng currentLocation) {
    if (!imageCreated) {
        imageCreated = true;
        Bitmap.Config conf = Bitmap.Config.ARGB_8888;
        bmp = Bitmap.createBitmap(400, 400, conf);
        Canvas canvas1 = new Canvas(bmp);

        Paint color = new Paint();
        color.setTextSize(30);
        color.setColor(Color.WHITE);

        BitmapFactory.Options opt = new BitmapFactory.Options();
        opt.inMutable = true;

        Bitmap imageBitmap=BitmapFactory.decodeResource(getResources(),
                R.drawable.messi,opt);
        Bitmap resized = Bitmap.createScaledBitmap(imageBitmap, 320, 320, true);
        canvas1.drawBitmap(resized, 40, 40, color);

        canvas1.drawText("Le Messi", 30, 40, color);

        currentLocationMarker = mMap.addMarker(new MarkerOptions().position(currentLocation)
                .icon(BitmapDescriptorFactory.fromBitmap(bmp))
                // Specifies the anchor to be at a particular point in the marker image.
                .anchor(0.5f, 1));
    } else {
        currentLocationMarker.setPosition(currentLocation);
    }

}

如何使用Android map API v2创建自定义形状的位图标记

4 个答案: