Java 使用MapBox将多个GeoJSON源添加到同一层
我正试图用多个GeoJSON文件中的数据填充地图。在下面的代码中,我创建了方法Java 使用MapBox将多个GeoJSON源添加到同一层,java,android,mapbox,geojson,mapbox-android,Java,Android,Mapbox,Geojson,Mapbox Android,我正试图用多个GeoJSON文件中的数据填充地图。在下面的代码中,我创建了方法GeoJSONToMap,调用该方法时,会向地图添加标记 GeoJSONToMap: public void GeoJSONToMap(@NonNull Style loadedMapStyle, String asset_id) { GeoJsonSource source = null; try { source = new GeoJsonSource("geojson-sou
GeoJSONToMap
,调用该方法时,会向地图添加标记
GeoJSONToMap
:
public void GeoJSONToMap(@NonNull Style loadedMapStyle, String asset_id) {
GeoJsonSource source = null;
try {
source = new GeoJsonSource("geojson-source", new URI(asset_id));
} catch (URISyntaxException e) {
e.printStackTrace();
}
loadedMapStyle.addSource(source);
Bitmap icon = BitmapFactory.decodeResource(getResources(), R.drawable.marker);
loadedMapStyle.addImage("marker", icon);
SymbolLayer symbolLayer = new SymbolLayer("layer-id", "geojson-source");
symbolLayer.setProperties(iconImage("marker"));
loadedMapStyle.addLayer(symbolLayer);
}
成功地将GeoJSON数据从one文件添加到地图:
public void onMapReady(@NonNull final MapboxMap mapboxMap) {
this.mapboxMap = mapboxMap;
mapboxMap.setStyle(Style.MAPBOX_STREETS,
new Style.OnStyleLoaded() {
@Override
public void onStyleLoaded(@NonNull Style style) {
GeoJSONToMap(style, "asset://the_GeoJSON_file");
当我尝试使用多个GeoJSON文件填充地图时,应用程序不会打开。我假设这个错误与图层创建有关,但是我没有找到答案
GeoJSONToMap(style, "asset://the_GeoJSON_file");
GeoJSONToMap(style, "asset://another_GeoJSON_file");
每次都使用相同的图层id,因为它是在
GeoJSONToMap
方法中硬编码的。每个层都需要有一个唯一的层id
每次都使用相同的源id,因为它是在GeoJSONToMap
方法中硬编码的。每个源都需要有一个唯一的源id
编辑:在下面添加代码。可以用不同的方式清理它,但是下面的代码按照您想要的方式工作。我调整并使用了应用程序的assets
文件夹中已有的GeoJSON文件
请参见GIF中的最终结果。您将看到黄色的pin图标来自一个geojson数据源,红色的pin来自另一个数据源
package com.mapbox.mapboxandroiddemo.examples.basics;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.util.Log;
import com.mapbox.mapboxandroiddemo.R;
import com.mapbox.mapboxsdk.Mapbox;
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.net.URI;
import java.net.URISyntaxException;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
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.iconIgnorePlacement;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.iconImage;
/**
* The most basic example of adding a map to an activity.
*/
public class SimpleMapViewActivity extends AppCompatActivity {
private MapView mapView;
private MapboxMap mapboxMap;
@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_basic_simple_mapview);
mapView = findViewById(R.id.mapView);
mapView.onCreate(savedInstanceState);
mapView.getMapAsync(new OnMapReadyCallback() {
@Override
public void onMapReady(@NonNull MapboxMap mapboxMap) {
mapboxMap.setStyle(Style.MAPBOX_STREETS, new Style.OnStyleLoaded() {
@Override
public void onStyleLoaded(@NonNull Style style) {
SimpleMapViewActivity.this.mapboxMap = mapboxMap;
// Map is set up and the style has loaded. Now you can add data or make other map adjustments.
GeoJSONToMap("source-id1", "first-layer-id", "asset://spinning_icon.geojson");
GeoJSONToMap("source-id2", "second-layer-id", "asset://la_heatmap_styling_points.geojson");
}
});
}
});
}
public void GeoJSONToMap(String sourceId, String layerId, String asset_id) {
mapboxMap.getStyle(new Style.OnStyleLoaded() {
@Override
public void onStyleLoaded(@NonNull Style style) {
try {
GeoJsonSource source = new GeoJsonSource(sourceId, new URI(asset_id));
style.addSource(source);
Bitmap icon;
if (layerId.equals("first-layer-id")) {
icon = BitmapFactory.decodeResource(getResources(), R.drawable.red_marker);
} else {
icon = BitmapFactory.decodeResource(getResources(), R.drawable.yellow_marker);
}
style.addImage(layerId + " marker", icon);
SymbolLayer symbolLayer = new SymbolLayer(layerId, sourceId);
symbolLayer.setProperties(
iconImage(layerId + " marker"),
iconAllowOverlap(true),
iconAnchor(ICON_ANCHOR_BOTTOM), // You should use this if you're using a pin-like icon image
iconIgnorePlacement(true)
);
style.addLayer(symbolLayer);
} catch (URISyntaxException e) {
e.printStackTrace();
}
}
});
}
// Add the mapView lifecycle to the activity's lifecycle methods
@Override
public void onResume() {
super.onResume();
mapView.onResume();
}
@Override
protected void onStart() {
super.onStart();
mapView.onStart();
}
@Override
protected void onStop() {
super.onStop();
mapView.onStop();
}
@Override
public void onPause() {
super.onPause();
mapView.onPause();
}
@Override
public void onLowMemory() {
super.onLowMemory();
mapView.onLowMemory();
}
@Override
protected void onDestroy() {
super.onDestroy();
mapView.onDestroy();
}
@Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
mapView.onSaveInstanceState(outState);
}
}
谢谢请你举个例子,你太棒了!非常感谢你,你说得非常清楚。希望你有一个愉快的一天。:五彩纸屑:很高兴你发现它很有用:)