我正在尝试构建具有一些弹出标记类型的东西和位置的基本应用。
我设法从外部GeoJsonSource将标记添加为符号层，并且运行良好。然后，我使用LocationComponent从Mapbox SDK for Android文档中添加了代码，但似乎无法加载地图。我本来以为起初onPermissionResult之后的样式重新加载是个问题，所以我尝试将其简化为enableLocationComponent();，但似乎没有参数就无法使用它。
几天来，我一直在尝试各种方式-将LocationComponent部分移至map.OnCreate之前的顶部，将onPermissionResult替换为其他选项。
我终于到了一个点，我可以使用enableLocationComponent中的一个参数来获取样式，从而构建没有错误的应用程序，但是样式仍然没有加载。我假设正在加载竞争的样式，或者与方法对象不一致的东西，但是我不知所措。如果有人能看到问题所在，将不胜感激。
下面是我的代码，其中包含字符串，功能和标注窗口文件：
MainActivity.java
package com.example.locativemedia;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.PointF;
import android.os.AsyncTask;
import android.os.Bundle;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;
import com.mapbox.android.core.permissions.PermissionsManager;
import com.mapbox.android.core.permissions.PermissionsListener;
import com.mapbox.geojson.Feature;
import com.mapbox.geojson.FeatureCollection;
import com.mapbox.mapboxsdk.Mapbox;
import com.mapbox.mapboxsdk.annotations.BubbleLayout;
import com.mapbox.mapboxsdk.geometry.LatLng;
import com.mapbox.mapboxsdk.location.LocationComponent;
import com.mapbox.mapboxsdk.location.LocationComponentActivationOptions;
import com.mapbox.mapboxsdk.location.modes.CameraMode;
import com.mapbox.mapboxsdk.location.modes.RenderMode;
import com.mapbox.mapboxsdk.maps.MapView;
import com.mapbox.mapboxsdk.maps.MapboxMap;
import com.mapbox.mapboxsdk.maps.OnMapReadyCallback;
import com.mapbox.mapboxsdk.maps.Style;
import com.mapbox.mapboxsdk.style.layers.SymbolLayer;
import com.mapbox.mapboxsdk.style.sources.GeoJsonSource;
import java.io.InputStream;
import java.lang.ref.WeakReference;
import java.nio.charset.Charset;
import java.util.HashMap;
import java.util.List;
import java.util.Objects;
import static com.mapbox.mapboxsdk.style.expressions.Expression.eq;
import static com.mapbox.mapboxsdk.style.expressions.Expression.get;
import static com.mapbox.mapboxsdk.style.expressions.Expression.literal;
import static com.mapbox.mapboxsdk.style.layers.Property.ICON_ANCHOR_BOTTOM;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.iconAllowOverlap;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.iconAnchor;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.iconImage;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.iconOffset;
/**
* Use a SymbolLayer to show a BubbleLayout above a SymbolLayer icon. This is a more performant
* way to show the BubbleLayout that appears when using the MapboxMap.addMarker() method.
*/
public class MainActivity extends AppCompatActivity implements
OnMapReadyCallback, MapboxMap.OnMapClickListener, PermissionsListener {
private static final String GEOJSON_SOURCE_ID = "GEOJSON_SOURCE_ID";
private static final String MARKER_IMAGE_ID = "MARKER_IMAGE_ID";
private static final String MARKER_LAYER_ID = "MARKER_LAYER_ID";
private static final String CALLOUT_LAYER_ID = "CALLOUT_LAYER_ID";
private static final String PROPERTY_SELECTED = "selected";
private static final String PROPERTY_NAME = "name";
private static final String PROPERTY_DESCRIPTION = "description";
private MapView mapView;
private MapboxMap mapboxMap;
private GeoJsonSource source;
private FeatureCollection featureCollection;
private PermissionsManager permissionsManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Mapbox access token is configured here. This needs to be called either in your application
// object or in the same activity which contains the mapview.
Mapbox.getInstance(this, getString(R.string.access_token));
// This contains the MapView in XML and needs to be called after the access token is configured.
setContentView(R.layout.activity_main);
// Initialize the map view
mapView = findViewById(R.id.mapView);
mapView.onCreate(savedInstanceState);
mapView.getMapAsync(this);
}
@Override
public void onMapReady(@NonNull final MapboxMap mapboxMap) {
this.mapboxMap = mapboxMap;
mapboxMap.setStyle(new Style.Builder().fromUri("mapbox://styles/cwilmott/ckbrpw01d29o31imqd2945ipn"),
style -> {
new LoadGeoJsonDataTask(MainActivity.this).execute();
mapboxMap.addOnMapClickListener(MainActivity.this);
});
}
@Override
public boolean onMapClick(@NonNull LatLng point) {
return handleClickIcon(mapboxMap.getProjection().toScreenLocation(point));
}
/**
* Sets up all of the sources and layers needed for this example
*
* @param collection the FeatureCollection to set equal to the globally-declared FeatureCollection
*/
public void setUpData(final FeatureCollection collection) {
featureCollection = collection;
if (mapboxMap != null) {
mapboxMap.getStyle(style -> {
setupSource(style);
setUpImage(style);
setUpMarkerLayer(style);
setUpInfoWindowLayer(style);
});
}
}
/**
* Adds the GeoJSON source to the map
*/
private void setupSource(@NonNull Style loadedStyle) {
source = new GeoJsonSource(GEOJSON_SOURCE_ID, featureCollection);
loadedStyle.addSource(source);
}
/**
* Adds the marker image to the map for use as a SymbolLayer icon
*/
private void setUpImage(@NonNull Style loadedStyle) {
loadedStyle.addImage(MARKER_IMAGE_ID, BitmapFactory.decodeResource(
this.getResources(), R.drawable.mapbox_marker_icon_default));
}
/**
* Updates the display of data on the map after the FeatureCollection has been modified
*/
private void refreshSource() {
if (source != null && featureCollection != null) {
source.setGeoJson(featureCollection);
}
}
/**
* Setup a layer with maki icons, eg. west coast city.
*/
private void setUpMarkerLayer(@NonNull Style loadedStyle) {
loadedStyle.addLayer(new SymbolLayer(MARKER_LAYER_ID, GEOJSON_SOURCE_ID)
.withProperties(
iconImage(MARKER_IMAGE_ID),
iconAllowOverlap(true),
iconOffset(new Float[]{0f, -8f})
));
}
/**
* Setup a layer with Android SDK call-outs
* <p>
* name of the feature is used as key for the iconImage
* </p>
*/
private void setUpInfoWindowLayer(@NonNull Style loadedStyle) {
loadedStyle.addLayer(new SymbolLayer(CALLOUT_LAYER_ID, GEOJSON_SOURCE_ID)
.withProperties(
/* show image with id title based on the value of the name feature property */
iconImage("{name}"),
/* set anchor of icon to bottom-left */
iconAnchor(ICON_ANCHOR_BOTTOM),
/* all info window and marker image to appear at the same time*/
iconAllowOverlap(true),
/* offset the info window to be above the marker */
iconOffset(new Float[]{-2f, -28f})
)
/* add a filter to show only when selected feature property is true */
.withFilter(eq((get(PROPERTY_SELECTED)), literal(true))));
}
/**
* This method handles click events for SymbolLayer symbols.
* <p>
* When a SymbolLayer icon is clicked, we moved that feature to the selected state.
* </p>
*
* @param screenPoint the point on screen clicked
*/
private boolean handleClickIcon(PointF screenPoint) {
List<Feature> features = mapboxMap.queryRenderedFeatures(screenPoint, MARKER_LAYER_ID);
if (!features.isEmpty()) {
String name = features.get(0).getStringProperty(PROPERTY_NAME);
List<Feature> featureList = featureCollection.features();
if (featureList != null) {
for (int i = 0; i < featureList.size(); i++) {
if (featureList.get(i).getStringProperty(PROPERTY_NAME).equals(name)) {
if (featureSelectStatus(i)) {
setFeatureSelectState(featureList.get(i), false);
} else {
setSelected(i);
}
}
}
}
return true;
} else {
return false;
}
}
/**
* Set a feature selected state.
*
* @param index the index of selected feature
*/
private void setSelected(int index) {
if (featureCollection.features() != null) {
Feature feature = featureCollection.features().get(index);
setFeatureSelectState(feature, true);
refreshSource();
}
}
/**
* Selects the state of a feature
*
* @param feature the feature to be selected.
*/
private void setFeatureSelectState(Feature feature, boolean selectedState) {
if (feature.properties() != null) {
feature.properties().addProperty(PROPERTY_SELECTED, selectedState);
refreshSource();
}
}
/**
* Checks whether a Feature's boolean "selected" property is true or false
*
* @param index the specific Feature's index position in the FeatureCollection's list of Features.
* @return true if "selected" is true. False if the boolean property is false.
*/
private boolean featureSelectStatus(int index) {
if (featureCollection == null) {
return false;
}
return featureCollection.features().get(index).getBooleanProperty(PROPERTY_SELECTED);
}
/**
* Invoked when the bitmaps have been generated from a view.
*/
public void setImageGenResults(HashMap<String, Bitmap> imageMap) {
if (mapboxMap != null) {
mapboxMap.getStyle(style -> {
// calling addImages is faster as separate addImage calls for each bitmap.
style.addImages(imageMap);
});
}
}
/**
* AsyncTask to load data from the assets folder.
*/
private static class LoadGeoJsonDataTask extends AsyncTask<Void, Void, FeatureCollection> {
private final WeakReference<MainActivity> activityRef;
LoadGeoJsonDataTask(MainActivity activity) {
this.activityRef = new WeakReference<>(activity);
}
@Override
protected FeatureCollection doInBackground(Void... params) {
MainActivity activity = activityRef.get();
if (activity == null) {
return null;
}
String geoJson = loadGeoJsonFromAsset(activity, "features.geojson");
return FeatureCollection.fromJson(geoJson);
}
@Override
protected void onPostExecute(FeatureCollection featureCollection) {
super.onPostExecute(featureCollection);
MainActivity activity = activityRef.get();
if (featureCollection == null || activity == null) {
return;
}
// This example runs on the premise that each GeoJSON Feature has a "selected" property,
// with a boolean value. If your data's Features don't have this boolean property,
// add it to the FeatureCollection 's features with the following code:
for (Feature singleFeature : featureCollection.features()) {
singleFeature.addBooleanProperty(PROPERTY_SELECTED, false);
}
activity.setUpData(featureCollection);
new GenerateViewIconTask(activity).execute(featureCollection);
}
static String loadGeoJsonFromAsset(Context context, String filename) {
try {
// Load GeoJSON file from local asset folder
InputStream is = context.getAssets().open(filename);
int size = is.available();
byte[] buffer = new byte[size];
is.read(buffer);
is.close();
return new String(buffer, Charset.forName("UTF-8"));
} catch (Exception exception) {
throw new RuntimeException(exception);
}
}
}
/**
* AsyncTask to generate Bitmap from Views to be used as iconImage in a SymbolLayer.
* <p>
* Call be optionally be called to update the underlying data source after execution.
* </p>
* <p>
* Generating Views on background thread since we are not going to be adding them to the view hierarchy.
* </p>
*/
private static class GenerateViewIconTask extends AsyncTask<FeatureCollection, Void, HashMap<String, Bitmap>> {
private final HashMap<String, View> viewMap = new HashMap<>();
private final WeakReference<MainActivity> activityRef;
private final boolean refreshSource;
GenerateViewIconTask(MainActivity activity, boolean refreshSource) {
this.activityRef = new WeakReference<>(activity);
this.refreshSource = refreshSource;
}
GenerateViewIconTask(MainActivity activity) {
this(activity, false);
}
@SuppressWarnings("WrongThread")
@Override
protected HashMap<String, Bitmap> doInBackground(FeatureCollection... params) {
MainActivity activity = activityRef.get();
if (activity != null) {
HashMap<String, Bitmap> imagesMap = new HashMap<>();
LayoutInflater inflater = LayoutInflater.from(activity);
FeatureCollection featureCollection = params[0];
for (Feature feature : featureCollection.features()) {
BubbleLayout bubbleLayout = (BubbleLayout)
inflater.inflate(R.layout.symbol_layer_info_window_layout_callout, null);
String name = feature.getStringProperty(PROPERTY_NAME);
TextView titleTextView = bubbleLayout.findViewById(R.id.info_window_title);
titleTextView.setText(name);
String style = feature.getStringProperty(PROPERTY_DESCRIPTION);
TextView descriptionTextView = bubbleLayout.findViewById(R.id.info_window_description);
descriptionTextView.setText(
String.format(activity.getString(R.string.description), style));
int measureSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
bubbleLayout.measure(measureSpec, measureSpec);
float measuredWidth = bubbleLayout.getMeasuredWidth();
bubbleLayout.setArrowPosition(measuredWidth / 2 - 5);
Bitmap bitmap = SymbolGenerator.generate(bubbleLayout);
imagesMap.put(name, bitmap);
viewMap.put(name, bubbleLayout);
}
return imagesMap;
} else {
return null;
}
}
@Override
protected void onPostExecute(HashMap<String, Bitmap> bitmapHashMap) {
super.onPostExecute(bitmapHashMap);
MainActivity activity = activityRef.get();
if (activity != null && bitmapHashMap != null) {
activity.setImageGenResults(bitmapHashMap);
if (refreshSource) {
activity.refreshSource();
}
}
Toast.makeText(activity, R.string.tap_on_marker_instruction, Toast.LENGTH_SHORT).show();
}
}
/**
* Utility class to generate Bitmaps for Symbol.
*/
private static class SymbolGenerator {
/**
* Generate a Bitmap from an Android SDK View.
*
* @param view the View to be drawn to a Bitmap
* @return the generated bitmap
*/
static Bitmap generate(@NonNull View view) {
int measureSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
view.measure(measureSpec, measureSpec);
int measuredWidth = view.getMeasuredWidth();
int measuredHeight = view.getMeasuredHeight();
view.layout(0, 0, measuredWidth, measuredHeight);
Bitmap bitmap = Bitmap.createBitmap(measuredWidth, measuredHeight, Bitmap.Config.ARGB_8888);
bitmap.eraseColor(Color.TRANSPARENT);
Canvas canvas = new Canvas(bitmap);
view.draw(canvas);
return bitmap;
}
}
//LOCATION SECTION
@SuppressWarnings({"MissingPermission"})
private void enableLocationComponent(@NonNull Style loadedMapStyle) {
// Check if permissions are enabled and if not request
if (PermissionsManager.areLocationPermissionsGranted(this)) {
// Get an instance of the component
LocationComponent locationComponent = mapboxMap.getLocationComponent();
// Activate with options
locationComponent.activateLocationComponent(
LocationComponentActivationOptions.builder(this, loadedMapStyle).build());
// Enable to make component visible
locationComponent.setLocationComponentEnabled(true);
// Set the component's camera mode
locationComponent.setCameraMode(CameraMode.TRACKING);
// Set the component's render mode
locationComponent.setRenderMode(RenderMode.COMPASS);
} else {
permissionsManager = new PermissionsManager(this);
permissionsManager.requestLocationPermissions(this);
}
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
permissionsManager.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
@Override
public void onExplanationNeeded(List<String> permissionsToExplain) {
Toast.makeText(this, R.string.user_location_permission_explanation, Toast.LENGTH_LONG).show();
}
@Override
public void onPermissionResult(boolean granted) {
if (granted) {
enableLocationComponent(Objects.requireNonNull(mapboxMap.getStyle()));
} else {
Toast.makeText(this, R.string.user_location_permission_not_granted, Toast.LENGTH_LONG).show();
}
}
@Override
@SuppressWarnings( {"MissingPermission"})
protected void onStart() {
super.onStart();
mapView.onStart();
}
@Override
public void onResume() {
super.onResume();
mapView.onResume();
}
@Override
public void onPause() {
super.onPause();
mapView.onPause();
}
@Override
protected void onStop() {
super.onStop();
mapView.onStop();
}
@Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
mapView.onSaveInstanceState(outState);
}
@Override
public void onLowMemory() {
super.onLowMemory();
mapView.onLowMemory();
}
@Override
protected void onDestroy() {
super.onDestroy();
if (mapboxMap != null) {
mapboxMap.removeOnMapClickListener(this);
}
mapView.onDestroy();
}
}
strings.xml
<resources>
<string name="app_name">Locative Media</string>
<string name="access_token">"pk.eyJ1IjoiY3dpbG1vdHQiLCJhIjoiY2s2bWRjb2tiMG1xMjNqcDZkbGNjcjVraiJ9.2nNOYL23A1cfZSE4hdC9ew"</string>
<string name="description">%1$s</string>
<string name="tap_on_marker_instruction">Tap on a marker</string>
<string name="user_location_permission_explanation">This app needs location permissions to work.</string>
<string name="user_location_permission_not_granted">You didn\'t grant location permissions.</string>
</resources>
symbol_layer_info_window_layout_callout.xml
<?xml version="1.0" encoding="utf-8"?>
<com.mapbox.mapboxsdk.annotations.BubbleLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
android:paddingBottom="6dp"
android:paddingEnd="8dp"
android:paddingLeft="8dp"
android:paddingRight="8dp"
android:paddingStart="8dp"
app:mapbox_bl_arrowDirection="bottom"
app:mapbox_bl_arrowHeight="8dp"
app:mapbox_bl_arrowWidth="8dp"
app:mapbox_bl_arrowPosition="50dp"
app:mapbox_bl_bubbleColor="@android:color/white"
app:mapbox_bl_cornersRadius="6dp"
app:mapbox_bl_strokeColor="@android:color/darker_gray"
app:mapbox_bl_strokeWidth="1dp">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:id="@+id/info_window_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:textSize="18sp"
android:textStyle="bold"
tools:text="Bubble title" />
<TextView
android:id="@+id/info_window_description"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@id/info_window_title"
android:textSize="12sp"
android:textStyle="italic"
tools:text="Bubble description" />
</LinearLayout>
</com.mapbox.mapboxsdk.annotations.BubbleLayout>
和features.geojson
{
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": {
"marker-color": "#7e7e7e",
"marker-size": "medium",
"marker-symbol": "",
"name": "Abandoned Building",
"description": "This block was bought by Nuffield Health and then abandoned."
},
"geometry": {
"type": "Point",
"coordinates": [
-2.22101,
53.45838
]
}
},
{
"type": "Feature",
"properties": {
"name": "Abandoned House",
"description": "This house has been boarded up for three years now. Foxes live there.",
"marker-color": "#7e7e7e",
"marker-size": "medium",
"marker-symbol": ""
},
"geometry": {
"type": "Point",
"coordinates": [
-2.2201326,
53.456842
]
}
},
{
"type": "Feature",
"properties": {
"name": "Squirrel",
"description": "A fat grey squirrel who was not afraid of people.",
"marker-color": "#7e7e7e",
"marker-size": "medium",
"marker-symbol": ""
},
"geometry": {
"type": "Point",
"coordinates": [
-2.2199295,
53.456497
]
}
},
{
"type": "Feature",
"properties": {
"marker-color": "#7e7e7e",
"marker-size": "medium",
"marker-symbol": "",
"name": "Old Tree",
"description": "This tree is really gnarly and old."
},
"geometry": {
"type": "Point",
"coordinates": [
-2.21619,
53.45523
]
}
}
]
}