ArcGIS for Android 100.3.0（4）：加载基础底图

基础底图

移动地图程序的基础，在于“一张图”，外业调绘、导航类、成果展示、统计应用等都需要一张基本的底图来支撑。往往底图的好坏决定了整个移动地图的根基。

加载在线基础底图

在线基础底图包括传统GIS（ArcGIS Server）和WebGIS（Online & Portal）。使用方式上确实不同，传统GIS是通过Layer直接对接地图服务（ArcGIS Server发布的）。WebGIS是同过ArcGISMap来对接WebMap。

1.传统GIS

对于一直使用ArcGIS Server发布地图服务的，可以直接使用地图服务（Layer）来加载在线的地图服务（ArcGIS Server）。

String url = "http://map.geoq.cn/arcgis/rest/services/ChinaOnlineCommunity/MapServer";
ArcGISTiledLayer arcGISTiledLayer = new ArcGISTiledLayer(url);
Basemap basemap = new Basemap(arcGISTiledLayer);
ArcGISMap arcGISMap = new ArcGISMap(basemap);
mMapView.setMap(arcGISMap);

2.WebGIS（Online & Portal）

通过Online或者Portal可以便捷快速的制作出更简洁智能的地图资源，用以表达我们的目的，对于移动端而言这些Web Map可以直接应用。

 String url = "http://www.arcgis.com/home/webmap/viewer.html?webmap=55c1665bcd064552944a9e8296271ec3";
  ArcGISMap arcGISMap = new ArcGISMap(url);
  mMapView.setMap(arcGISMap);

  Basemap basemap = arcGISMap.getBasemap(); //获取底图
  LayerList operationalLayers = arcGISMap.getOperationalLayers(); //获取业务图层

3.在线矢量切片：ArcGISVectorTiledLayer

String url = "https://www.arcgis.com/home/item.html?id=e19e9330bf08490ca8353d76b5e2e658";
ArcGISVectorTiledLayer arcGISVectorTiledLayer = new ArcGISVectorTiledLayer(url);
Basemap basemap = new Basemap(arcGISVectorTiledLayer);
ArcGISMap arcGISMap = new ArcGISMap(basemap);
mMapView.setMap(arcGISMap);
Viewpoint vp = new Viewpoint(47.606726, -122.335564, 72223.819286);
arcGISMap.setInitialViewpoint(vp);

加载离线基础底图

离线基础底图最传统的方式是直接拷贝ArcGIS Server服务的切片成果，存在的问题是无论使用松散型还是紧凑型都包含太多碎小文件，部署不便。

TPK文件便是为了解决多碎小文件问题。但是依然存在文件太大的问题，动辄十G甚至几十G。而矢量切片（VTPK）在于解决文件太大的问题。

1.TPK

        String path = Environment.getExternalStorageDirectory().getAbsolutePath() + "/yxt.tpk";
        TileCache titleCache = new TileCache(path);
        ArcGISTiledLayer arcGISTiledLayer = new ArcGISTiledLayer(titleCache);
        Basemap basemap = new Basemap(arcGISTiledLayer);
        ArcGISMap arcGISMap = new ArcGISMap(basemap);
        mMapView.setMap(arcGISMap);

2.矢量切片：VTPK

String path = "/sdcard/Hymn/basemap/dzzhdjfb.vtpk";
ArcGISVectorTiledLayer mainArcGISVectorTiledLayer = new ArcGISVectorTiledLayer(path);
Basemap mainBasemap = new Basemap(mainArcGISVectorTiledLayer);
ArcGISMap mainArcGISMap = new ArcGISMap(mainBasemap);
mMapView.setMap(mainArcGISMap);

3.MMPK（Basemap）

通过ArcGIS Pro可以制作包含基础底图（Basemap）的MMPK，MMPK文件解析后，基础底图（Basemap）中的图层会解析为MobileBasemapLayer，只提供浏览功能。当然，亚洲字符的支持情况在安卓端不是特别好。

String path = "/sdcard/Hymn/basemap/MobileBasemapLayer.mmpk";
        final MobileMapPackage mobileMapPackage = new MobileMapPackage(path);
        mobileMapPackage.loadAsync();
        mobileMapPackage.addDoneLoadingListener(new Runnable() {
            @Override
            public void run() {
                LoadStatus loadStatus = mobileMapPackage.getLoadStatus();
                if (loadStatus == LoadStatus.LOADED) {
                    List<ArcGISMap> maps = mobileMapPackage.getMaps();
                    ArcGISMap arcGISMap = maps.get(0);
                    Basemap basemap = arcGISMap.getBasemap();
                    LayerList operationalLayers = arcGISMap.getOperationalLayers();
                    mMapView.setMap(arcGISMap);
                }
            }
        });

底图的切换

在Runtime100里，MapView是通过ArcGISMap类来完成图层的管理。

ArcGISMap类是将底图和业务图层分开的，对于底图，ArcGISMap里用了Baemap类来进行管理。

上面已经介绍了加载底图，现在就讲讲底图的切换。

如果我们要切换底图时候，仅需要给ArcGISMap类重新赋值一个底图即可。

 Basemap basemap = new Basemap(layer);
 arcGISMap.setBasemap(basemap);

下面来看下官方切换底图的案例：

布局：

<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <!-- The main content view -->
    <FrameLayout
        android:id="@+id/fl_content"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <com.esri.arcgisruntime.mapping.view.MapView
            android:id="@+id/mapview"
            android:layout_width="match_parent"
            android:layout_height="match_parent"></com.esri.arcgisruntime.mapping.view.MapView>
    </FrameLayout>

    <!-- The navigation drawer -->
    <ListView
        android:id="@+id/listview"
        android:layout_width="200dp"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:background="@android:color/background_light"
        android:choiceMode="singleChoice"
        android:divider="#BDBDBD"
        android:dividerHeight="1dp" />
</android.support.v4.widget.DrawerLayout>

Activity:

public class ChangeBasemapActivity extends AppCompatActivity {

    @BindView(R.id.mapview)
    MapView mMapview;
    @BindView(R.id.fl_content)
    FrameLayout mFlContent;
    @BindView(R.id.listview)
    ListView mListview;
    @BindView(R.id.drawer_layout)
    DrawerLayout mDrawerLayout;

    private ArcGISMap mArcGISMap;

    private String[] mNavigationDrawerItemTitles;

    private ActionBarDrawerToggle mDrawerToggle;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_change_basemap);
        ButterKnife.bind(this);

        //侧滑页面数据
        mNavigationDrawerItemTitles = getResources().getStringArray(R.array.basemap_types);

        if (getSupportActionBar() != null) {
            getSupportActionBar().setDisplayHomeAsUpEnabled(true);
            getSupportActionBar().setHomeButtonEnabled(true);
            getSupportActionBar().setTitle("底图切换");
        }

        mArcGISMap = new ArcGISMap(Basemap.Type.TOPOGRAPHIC, 47.6047381, -122.3334255, 12);
        mMapview.setMap(mArcGISMap);

        addDrawerItems();

        setupDrawer();
    }

    private void addDrawerItems() {
        ArrayAdapter<String> mAdapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1,
                mNavigationDrawerItemTitles);
        mListview.setAdapter(mAdapter);

        mListview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int position, long id) {
                selectBasemap(position);
            }
        });
    }

    /**
     * Set up the navigation drawer
     */
    private void setupDrawer() {
        mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout, R.string.drawer_open, R.string.drawer_close) {

            /** Called when a drawer has settled in a completely open state. */
            public void onDrawerOpened(View drawerView) {
                super.onDrawerOpened(drawerView);
                //getSupportActionBar().setTitle(mActivityTitle);
                invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()
            }

            /** Called when a drawer has settled in a completely closed state. */
            public void onDrawerClosed(View view) {
                super.onDrawerClosed(view);
                invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()
            }
        };

        mDrawerToggle.setDrawerIndicatorEnabled(true);
        mDrawerLayout.addDrawerListener(mDrawerToggle);
    }


    /**
     * Select the Basemap item based on position in the navigation drawer
     *
     * @param position order int in navigation drawer
     */
    private void selectBasemap(int position) {
        // update selected item and title, then close the drawer
        mListview.setItemChecked(position, true);
        mDrawerLayout.closeDrawer(mListview);

        // if-else is used because this sample is used elsewhere as a Library module
        if (position == 0) {
            // position 0 = Streets
            mArcGISMap.setBasemap(Basemap.createStreets());
            getSupportActionBar().setTitle(mNavigationDrawerItemTitles[position]);
        } else if (position == 1) {
            // position 1 = Navigation Vector
            mArcGISMap.setBasemap(Basemap.createNavigationVector());
            getSupportActionBar().setTitle(mNavigationDrawerItemTitles[position]);
        } else if (position == 2) {
            // position 2 = Topographic
            mArcGISMap.setBasemap(Basemap.createTopographic());
            getSupportActionBar().setTitle(mNavigationDrawerItemTitles[position]);
        } else if (position == 3) {
            // position 3 = Topographic Vector
            mArcGISMap.setBasemap(Basemap.createTopographicVector());
            getSupportActionBar().setTitle(mNavigationDrawerItemTitles[position]);
        } else if (position == 4) {
            // position 3 = Gray Canvas
            mArcGISMap.setBasemap(Basemap.createLightGrayCanvas());
            getSupportActionBar().setTitle(mNavigationDrawerItemTitles[position]);
        } else if (position == 5) {
            // position 3 = Gray Canvas Vector
            mArcGISMap.setBasemap(Basemap.createLightGrayCanvasVector());
            getSupportActionBar().setTitle(mNavigationDrawerItemTitles[position]);
        }
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Activate the navigation drawer toggle
        return (mDrawerToggle.onOptionsItemSelected(item)) || super.onOptionsItemSelected(item);
    }

    @Override
    protected void onPostCreate(Bundle savedInstanceState) {
        super.onPostCreate(savedInstanceState);
        mDrawerToggle.syncState();
    }

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        mDrawerToggle.onConfigurationChanged(newConfig);
    }

    @Override
    protected void onResume() {
        super.onResume();
        mMapview.resume();
    }

    @Override
    protected void onPause() {
        super.onPause();
        mMapview.pause();

    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        mMapview.dispose();
    }

}