topic Re: Not displaying polyline on the map in ArcGIS Runtime SDK for Android Questions

Not displaying polyline on the map

thilibu — Thu, 12 Mar 2015 03:38:32 GMT

Hello every one. I'm new to ArcGIS and I want to add path(polyline) on the map after giving coordinates where to draw. I follow the guide Display Information -> add graphics and text. But not displaying the path and even not occur any error.

MapView mMapView = null;

// The basemap switching menu items.

MenuItem mStreetsMenuItem = null;

MenuItem mTopoMenuItem = null;

MenuItem mGrayMenuItem = null;

MenuItem mOceansMenuItem = null;

// Create MapOptions for each type of basemap.

final MapOptions mTopoBasemap = new MapOptions(MapType.TOPO);

final MapOptions mStreetsBasemap = new MapOptions(MapType.STREETS);

final MapOptions mGrayBasemap = new MapOptions(MapType.GRAY);

final MapOptions mOceansBasemap = new MapOptions(MapType.OCEANS);

ArcGISTiledMapServiceLayer tms = new ArcGISTiledMapServiceLayer("http://services.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer");

// The current map extent, use to set the extent of the map after switching basemaps.

Polygon mCurrentMapExtent = null;

GraphicsLayer mLocationLayer;

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_gis2);

// Retrieve the map and initial extent from XML layout

mMapView = (MapView) findViewById(R.id.map);

mLocationLayer = new GraphicsLayer();

mMapView.addLayer(tms);

// Set the Esri logo to be visible, and enable map to wrap around date line.

mMapView.setEsriLogoVisible(false);

mMapView.enableWrapAround(true);

SimpleLineSymbol lineSymbol = new SimpleLineSymbol(Color.GREEN, 3, SimpleLineSymbol.STYLE.DASH);

Polyline lineGeometry = new Polyline();

lineGeometry.startPath(-302557, 7570663);

lineGeometry.lineTo(-302959, 7570868);

lineGeometry.lineTo(-303042, 7571220);

lineGeometry.lineTo(-302700, 7571803);

lineGeometry.lineTo(-304043, 7576654);

lineGeometry.lineTo(-300544, 7585289);

lineGeometry.lineTo(-294365, 7592435);

lineGeometry.lineTo(-290122, 7594445);

lineGeometry.lineTo(-285283, 7595488);

Graphic lineGraphic = new Graphic(lineGeometry, lineSymbol);

mLocationLayer.addGraphic(lineGraphic);

// Set a listener for map status changes; this will be called when switching basemaps.

mMapView.setOnStatusChangedListener(new OnStatusChangedListener() {

private static final long serialVersionUID = 1L;

@Override

public void onStatusChanged(Object source, STATUS status) {

// Set the map extent once the map has been initialized, and the basemap is added

// or changed; this will be indicated by the layer initialization of the basemap layer. As there is only

// a single layer, there is no need to check the source object.

if ((source == mMapView) && (status == STATUS.INITIALIZED)) {

boolean mIsMapLoaded = true;

}

});

}

@Override

public boolean onCreateOptionsMenu(Menu menu) {

// Inflate the menu; this adds items from the Menu XML to the action bar, if present.

getMenuInflater().inflate(R.menu.menu_gis2, menu);

// Get the basemap switching menu items.

mStreetsMenuItem = menu.getItem(0);

mTopoMenuItem = menu.getItem(1);

mGrayMenuItem = menu.getItem(2);

mOceansMenuItem = menu.getItem(3);

// Also set the topo basemap menu item to be checked, as this is the default.

mTopoMenuItem.setChecked(true);

return true;

}

@Override

public boolean onOptionsItemSelected(MenuItem item) {

// Save the current extent of the map before changing the map.

// mCurrentMapExtent = mMapView.getExtent();

// Handle menu item selection.

switch (item.getItemId()) {

case R.id.World_Street_Map:

mMapView.setMapOptions(mStreetsBasemap);

mStreetsMenuItem.setChecked(true);

return true;

case R.id.World_Topo:

mMapView.setMapOptions(mTopoBasemap);

mTopoMenuItem.setChecked(true);

return true;

case R.id.Gray:

mMapView.setMapOptions(mGrayBasemap);

mGrayMenuItem.setChecked(true);

return true;

case R.id.Ocean_Basemap:

mMapView.setMapOptions(mOceansBasemap);

mOceansMenuItem.setChecked(true);

return true;

default:

return super.onOptionsItemSelected(item);

}

@Override

protected void onPause() {

super.onPause();

mMapView.pause();

}

@Override

protected void onResume() {

super.onResume();

mMapView.unpause();

}

Please help me on this. Thank you

Re: Not displaying polyline on the map

ÅsaWegelius — Thu, 12 Mar 2015 12:27:18 GMT

I had the same problem (actually today like you ) and it occurs when the spatial references are not the same. This is how I solved it:

1. Make a field for the maps spatial reference

private SpatialReference mapSpatialReference;

2. Save the maps spatial reference in onCreateView. You need to do it this way to be sure the map is fully initialized before you try to get the value.

        mapView = (MapView) view.findViewById(R.id.map);
        mapView.setOnStatusChangedListener(new OnStatusChangedListener() {
            private static final long serialVersionUID = 1L;
            public void onStatusChanged(Object source, STATUS status) {
                if (OnStatusChangedListener.STATUS.INITIALIZED == status && source == mapView) {
                    mapSpatialReference = mapView.getSpatialReference();
                }
            }
        });

3. Check if the spatial references match and use a GeometryEngine to fix it if not.

        if(route != null) {
            locationDisplayManager.stop();
            for (Graphic graphic : route.getGraphics()) {
                if (route.getSpatialReference().equals(mapSpatialReference)) {
                    SimpleLineSymbol lineSymbol = new SimpleLineSymbol(R.color.orange, 5, SimpleLineSymbol.STYLE.SOLID);
                    Polyline poly = (Polyline)graphic.getGeometry();
                    Graphic routeGraphic = new Graphic(poly, lineSymbol);
                    myGraphicsLayer.addGraphic(routeGraphic);
                    mapView.setExtent(routeGraphic.getGeometry(), 15);
                }
                else{
                    SimpleLineSymbol lineSymbol = new SimpleLineSymbol(R.color.orange, 5, SimpleLineSymbol.STYLE.SOLID);
                    GeometryEngine engine = new GeometryEngine();
                    Polyline poly = (Polyline)engine.project(graphic.getGeometry(), route.getSpatialReference(), mapSpatialReference);
                    Graphic routeGraphic = new Graphic(poly, lineSymbol);
                    myGraphicsLayer.addGraphic(routeGraphic);
                    mapView.setExtent(routeGraphic.getGeometry(), 15);
                }
            }

Hope it helps.

Now I only have to find out why my polyline is black instead of orange and why the setExtent doesn't work. The latter is probobly also related to the spatial reference.

Re: Not displaying polyline on the map

thilibu — Thu, 12 Mar 2015 13:28:16 GMT

thnx a lot.. Here route means object from Route or another?

Re: Not displaying polyline on the map

ÅsaWegelius — Thu, 12 Mar 2015 13:39:40 GMT

I just copied from a project I'm working on. The Route is a GPFeatureRecordSetLayer I get back from a service.

Re: Not displaying polyline on the map

ÅsaWegelius — Sun, 15 Mar 2015 13:03:12 GMT

I try show in your code instead:

    MapView mMapView = null;
    // The basemap switching menu items.
    MenuItem mStreetsMenuItem = null;
    MenuItem mTopoMenuItem = null;
    MenuItem mGrayMenuItem = null;
    MenuItem mOceansMenuItem = null;
    // Create MapOptions for each type of basemap.
    final MapOptions mTopoBasemap = new MapOptions(MapOptions.MapType.TOPO);
    final MapOptions mStreetsBasemap = new MapOptions(MapOptions.MapType.STREETS);
    final MapOptions mGrayBasemap = new MapOptions(MapOptions.MapType.GRAY);
    final MapOptions mOceansBasemap = new MapOptions(MapOptions.MapType.OCEANS);
// Here is the field for saving the maps spatial reference
    private SpatialReference mapSpatialReference;
    ArcGISTiledMapServiceLayer tms = new ArcGISTiledMapServiceLayer("http://services.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer");
    // The current map extent, use to set the extent of the map after switching basemaps.
    Polygon mCurrentMapExtent = null;
    GraphicsLayer mLocationLayer;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_gis2);
        // Retrieve the map and initial extent from XML layout
        mMapView = (MapView) findViewById(R.id.map);
        mLocationLayer = new GraphicsLayer();
        mMapView.addLayer(tms);
        // Set the Esri logo to be visible, and enable map to wrap around date line.
        mMapView.setEsriLogoVisible(false);
        mMapView.enableWrapAround(true);
        // Set a listener for map status changes; this will be called when switching basemaps.
        mMapView.setOnStatusChangedListener(new OnStatusChangedListener() {
            private static final long serialVersionUID = 1L;
            @Override
            public void onStatusChanged(Object source, STATUS status) {
                // Set the map extent once the map has been initialized, and the basemap is added
                // or changed; this will be indicated by the layer initialization of the basemap layer. As there is only
                // a single layer, there is no need to check the source object.
                if ((source == mMapView) && (status == STATUS.INITIALIZED)) {
                    boolean mIsMapLoaded = true;
                    mapSpatialReference = mMapView.getSpatialReference();
                    // if you need to check the maps spatial reference before you draw you do like this to ensure
                    //you don't draw before the map is initialized
                    writePolyline();
                }
            }
        });
    }
    public void writePolyline(){
        SimpleLineSymbol lineSymbol = new SimpleLineSymbol(Color.GREEN, 3, SimpleLineSymbol.STYLE.DASH);
        Polyline lineGeometry = new Polyline();
        lineGeometry.startPath(-302557, 7570663);
        lineGeometry.lineTo(-302959, 7570868);
        lineGeometry.lineTo(-303042, 7571220);
        lineGeometry.lineTo(-302700, 7571803);
        lineGeometry.lineTo(-304043, 7576654);
        lineGeometry.lineTo(-300544, 7585289);
        lineGeometry.lineTo(-294365, 7592435);
        lineGeometry.lineTo(-290122, 7594445);
        lineGeometry.lineTo(-285283, 7595488);
        GeometryEngine engine = new GeometryEngine();
        Graphic lineGraphic = new Graphic(lineGeometry, lineSymbol);
// here I get the maps corners to show that the polyline is way outside its boundaries so you either use points inside
// or finds the spatial reference from the map you got the points from and use an engine as I do below to projet it to the correct one
        Polygon mapExtent = mMapView.getExtent();
        System.out.println("mapViews extent " + mapExtent.toString() + " no of points " + mapExtent.getPointCount());
        for(int i = 0; i < mapExtent.getPointCount(); i++){
            System.out.println("point " + i +" " + mapExtent.getPoint(i).getX() + " x " + mapExtent.getPoint(i).getY() + " y ");
        }
        //PUT_YOUR POLYLINES SPATIAL REFERENCE WHERE IT IS SpatialReference.create(4326) NOW
       engine.project(lineGeometry, SpatialReference.create(4326), mapSpatialReference);
        mLocationLayer.addGraphic(lineGraphic);
    }

Re: Not displaying polyline on the map

thilibu — Mon, 16 Mar 2015 08:05:24 GMT

thnk u very much..