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GWT GoogleMaps Hide default layers using styles

I use GWT and GWT API GoogleMaps ( v3.8.0 ). Everything is fine and works fine for me.

However, I would like to disable some of the default features that come with GoogleMaps, such as street names, the ability to click restaurants, etc. Basically, I would like it to actually be a map layer, which I add my own custom layers.

I thought I could do this using styles. I am trying to use MapTypeStyler with visibility using MapTypeStyle of any type that I wanted to disable (in this case, MapTypeStyle.ROAD).

Here is the test code I'm trying to run:

package com.test.client; import com.google.gwt.ajaxloader.client.AjaxLoader; import com.google.gwt.ajaxloader.client.AjaxLoader.AjaxLoaderOptions; import com.google.gwt.core.client.EntryPoint; import com.google.gwt.core.client.JsArray; import com.google.gwt.dom.client.Document; import com.google.maps.gwt.client.GoogleMap; import com.google.maps.gwt.client.LatLng; import com.google.maps.gwt.client.MapOptions; import com.google.maps.gwt.client.MapTypeId; import com.google.maps.gwt.client.MapTypeStyle; import com.google.maps.gwt.client.MapTypeStyleElementType; import com.google.maps.gwt.client.MapTypeStyleFeatureType; import com.google.maps.gwt.client.MapTypeStyler; public class GwtTest implements EntryPoint { @Override public void onModuleLoad() { AjaxLoaderOptions options = AjaxLoaderOptions.newInstance(); options.setOtherParms("sensor=false"); Runnable callback = new Runnable() { public void run() { createMap(); } }; AjaxLoader.loadApi("maps", "3", callback, options); } public void createMap() { JsArray<MapTypeStyle> styles = (JsArray<MapTypeStyle>) JsArray.<MapTypeStyle>createArray(); JsArray<MapTypeStyler> roadStylers = (JsArray<MapTypeStyler>) JsArray.<MapTypeStyler>createArray(); MapTypeStyler roadStyler = MapTypeStyler.visibility("off"); roadStylers.push(roadStyler); MapTypeStyle roadStyle = MapTypeStyle.create(); roadStyle.setStylers(roadStylers); roadStyle.setFeatureType(MapTypeStyleFeatureType.ROAD); //this is line 43 roadStyle.setElementType(MapTypeStyleElementType.ALL); styles.push(roadStyle); MapOptions mapOpts = MapOptions.create(); mapOpts.setZoom(4); mapOpts.setCenter(LatLng.create(37.09024, -95.712891)); mapOpts.setMapTypeId(MapTypeId.TERRAIN); mapOpts.setStreetViewControl(false); mapOpts.setStyles(styles); final GoogleMap map = GoogleMap.create(Document.get().getElementById("map_canvas"), mapOpts); } }

However, when I run this, I get an exception:

 14:49:52.756 [ERROR] [gwttest] Uncaught exception escaped java.lang.ExceptionInInitializerError: null at com.test.client.GwtTest.createMap(GwtTest.java:43) at com.test.client.GwtTest$1.run(GwtTest.java:25) at com.google.gwt.ajaxloader.client.ExceptionHelper.runProtected(ExceptionHelper.java:36) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:483) at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103) at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71) at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172) at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessages(BrowserChannelServer.java:293) at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:547) at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:364) at java.lang.Thread.run(Thread.java:745) Caused by: java.lang.NullPointerException: null at com.google.maps.gwt.client.MapTypeStyleFeatureType$.register(MapTypeStyleFeatureType.java:227) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:483) at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103) at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71) at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172) at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessagesWhileWaitingForReturn(BrowserChannelServer.java:338) at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:219) at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:136) at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:576) at com.google.gwt.dev.shell.ModuleSpace.invokeNativeObject(ModuleSpace.java:284) at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeObject(JavaScriptHost.java:91) at com.google.maps.gwt.client.MapTypeStyleFeatureType$.create(MapTypeStyleFeatureType.java) at com.google.maps.gwt.client.MapTypeStyleFeatureType$.&lt;clinit&gt;(MapTypeStyleFeatureType.java:39) at com.test.client.GwtTest.createMap(GwtTest.java:43) at com.test.client.GwtTest$1.run(GwtTest.java:25) at com.google.gwt.ajaxloader.client.ExceptionHelper.runProtected(ExceptionHelper.java:36) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:483) at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103) at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71) at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172) at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessages(BrowserChannelServer.java:293) at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:547) at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:364) at java.lang.Thread.run(Thread.java:745)

It is strange that the exception seems to be internal to GoogleMaps, so I really don't know what is going on?

Am I doing something obviously dumb with styles?

Edit: I also asked this question on the GWT forum.

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1 answer

I found one solution related to writing native JavaScript that bypasses the Gmail GoogleMaps API:

 package com.test.client; import com.google.gwt.ajaxloader.client.AjaxLoader; import com.google.gwt.ajaxloader.client.AjaxLoader.AjaxLoaderOptions; import com.google.gwt.core.client.EntryPoint; import com.google.gwt.dom.client.Document; import com.google.maps.gwt.client.GoogleMap; import com.google.maps.gwt.client.LatLng; import com.google.maps.gwt.client.MapOptions; import com.google.maps.gwt.client.MapTypeId; public class GwtTest implements EntryPoint { @Override public void onModuleLoad() { AjaxLoaderOptions options = AjaxLoaderOptions.newInstance(); options.setOtherParms("sensor=false"); Runnable callback = new Runnable() { public void run() { createMap(); } }; AjaxLoader.loadApi("maps", "3", callback, options); } public void createMap() { MapOptions mapOpts = MapOptions.create(); mapOpts.setZoom(4); mapOpts.setCenter(LatLng.create(37.09024, -95.712891)); mapOpts.setMapTypeId(MapTypeId.TERRAIN); mapOpts.setStreetViewControl(false); GoogleMap map = GoogleMap.create(Document.get().getElementById("map_canvas"), mapOpts); styleMap(map); } public native void styleMap(GoogleMap map) /*-{ map.set('styles', [ { "featureType": "road", "stylers": [ { "visibility": "off" } ] },{ "featureType": "poi", "stylers": [ { "visibility": "off" } ] },{ "stylers": [ { "invert_lightness": true } ] } ]); }-*/; }

I would still be interested to know if there is a workaround for pure Java, but if anyone else has this problem, this native approach works. And it has an added bonus, which it works directly with JSON, which you can export from the GoogleMaps style wizard .

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