Simple Renderer

Screenshot of Simple Renderer App

Description

This sample demonstrates how to create a simple renderer and add it to a graphics overlay. Renderers define the symbology for all graphics in a graphics overlay (unless they are overridden by setting the symbol directly on the graphic). Simple renderers can also be defined on feature layers using the same code.

Features

  • Graphic
  • GraphicsOverlay
  • SimpleMarkerSymbol
  • SimpleRenderer

Developer Pattern

A simple renderer is created using a simple marker symbol (red cross) and set onto a graphics overlay. 3 points are created and added to graphics which are then added to the graphics overlay. The graphics overlay is added to the map view so it is visible, all graphics are then styled with the same symbol that was defined in the renderer.

//create a simple symbol for use in a simple renderer
SimpleMarkerSymbol symbol = new SimpleMarkerSymbol(SimpleMarkerSymbol.Style.CROSS, Color.RED, 12); //size 12, style of cross
SimpleRenderer renderer = new SimpleRenderer(symbol);

//apply the renderer to the graphics overlay (so all graphics will use the same symbol from the renderer)
graphicOverlay.setRenderer(renderer);

Code

/* Copyright 2016 Esri
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

package com.esri.arcgisruntime.sample.simplerenderer;

import android.graphics.Color;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;

import com.esri.arcgisruntime.geometry.Envelope;
import com.esri.arcgisruntime.geometry.Point;
import com.esri.arcgisruntime.geometry.SpatialReferences;
import com.esri.arcgisruntime.mapping.ArcGISMap;
import com.esri.arcgisruntime.mapping.Basemap;
import com.esri.arcgisruntime.mapping.view.Graphic;
import com.esri.arcgisruntime.mapping.view.GraphicsOverlay;
import com.esri.arcgisruntime.mapping.view.MapView;
import com.esri.arcgisruntime.symbology.SimpleMarkerSymbol;
import com.esri.arcgisruntime.symbology.SimpleRenderer;


public class MainActivity extends AppCompatActivity {

    MapView mMapView;

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

        //Create points to add graphics to the map to allow a renderer to style them
        //These are in WGS84 coordinates (Long, Lat)
        Point oldFaithfullPoint = new Point(-110.828140, 44.460458, SpatialReferences.getWgs84());
        Point cascadeGeyserPoint = new Point(-110.829004, 44.462438, SpatialReferences.getWgs84());
        Point plumeGeyserPoint = new Point(-110.829381, 44.462735, SpatialReferences.getWgs84());
        //Use the farthest points to create an envelope to use for the map views visible area
        Envelope initialEnvelope = new Envelope(oldFaithfullPoint, plumeGeyserPoint);

        // inflate MapView from layout
        mMapView = (MapView) findViewById(R.id.mapView);
        // create a map with the imagery basemap. This will set the map to have a WebMercator spatial reference
        ArcGISMap map = new ArcGISMap(Basemap.createImageryWithLabels());
        // set the map to be displayed in the mapview
        mMapView.setMap(map);

        //set initial envelope on the map view sith some padding so all points will be visible
        //This envelope is using the WGS84 points above, but is reprojected by the mapview into the maps spatial reference, so its works fine
        mMapView.setViewpointGeometryAsync(initialEnvelope, 100);

        // create a new graphics overlay and add it to the mapview
        GraphicsOverlay graphicOverlay = new GraphicsOverlay();
        mMapView.getGraphicsOverlays().add(graphicOverlay);

        //[DocRef: Name=Simple Renderer, Category=Fundamentals, Topic=Symbols and Renderers]
        //create a simple symbol for use in a simple renderer
        SimpleMarkerSymbol symbol = new SimpleMarkerSymbol(SimpleMarkerSymbol.Style.CROSS, Color.RED, 12); //size 12, style of cross
        SimpleRenderer renderer = new SimpleRenderer(symbol);

        //apply the renderer to the graphics overlay (so all graphics will use the same symbol from the renderer)
        graphicOverlay.setRenderer(renderer);
        //[DocRef: END]

        //create graphics from the geyser location points. NOTE: no need to set the symbol on the graphic because the renderer takes care of it
        //The points are in WGS84, but graphics get reprojected automatically, so they work fine in a map with a spatial reference of web mercator
        Graphic oldFaithfullGraphic = new Graphic(oldFaithfullPoint);
        Graphic cascadeGeyserGraphic = new Graphic(cascadeGeyserPoint);
        Graphic plumeGeyserGraphic = new Graphic(plumeGeyserPoint);
        graphicOverlay.getGraphics().add(oldFaithfullGraphic);
        graphicOverlay.getGraphics().add(cascadeGeyserGraphic);
        graphicOverlay.getGraphics().add(plumeGeyserGraphic);

    }

    @Override
    protected void onPause(){
        super.onPause();
        // pause MapView
        mMapView.pause();
    }

    @Override
    protected void onResume(){
        super.onResume();
        // resume MapView
        mMapView.resume();
    }
}