IllegalArgumentException: width and height must be > 0 during zoomOut in Google MapView

I'm trying to zoom in on a Google MapView on step in the oncreateMethod of my Activity. Everytime I try to zoom the map via the mapController I get an IllegalArgumentException:

04-15 10:16:51.012: ERROR/AndroidRuntime(528): java.lang.RuntimeException: Unable to start activity ComponentInfo{android.client/android.client.ui.showstores.StoreMap}: java.lang.IllegalArgumentException: width and height must be > 0

This Exception is thrown if I call the zoomOut or zoomIn function of MapController. Sadly the zoomIn function I'm using does not take any arguments.

The onCreateMethod where I'm calling the zoom functions looks like this:

    mapView = (MapView) findViewById(R.id.map);
    mapView.setBuiltInZoomControls(true);
    MapController mapController = mapVie开发者_如何学编程w.getController();
    mapController.zoomIn();

I'm a little bit at loss here because I'm doing nothing special.

The whole stacktrace is:

04-15 10:16:51.012: ERROR/AndroidRuntime(528): java.lang.RuntimeException: Unable to start activity ComponentInfo{android.client/android.client.ui.showstores.StoreMap}: java.lang.IllegalArgumentException: width and height must be > 0
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2401)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2417)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at android.app.ActivityThread.access$2100(ActivityThread.java:116)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1794)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at android.os.Handler.dispatchMessage(Handler.java:99)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at android.os.Looper.loop(Looper.java:123)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at android.app.ActivityThread.main(ActivityThread.java:4203)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at java.lang.reflect.Method.invokeNative(Native Method)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at java.lang.reflect.Method.invoke(Method.java:521)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at dalvik.system.NativeStart.main(Native Method)
04-15 10:16:51.012: ERROR/AndroidRuntime(528): Caused by: java.lang.IllegalArgumentException: width and height must be > 0
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at android.graphics.Bitmap.nativeCreate(Native Method)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at android.graphics.Bitmap.createBitmap(Bitmap.java:468)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at com.google.android.maps.ZoomHelper.createSnapshot(ZoomHelper.java:305)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at com.google.android.maps.ZoomHelper.doZoom(ZoomHelper.java:137)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at com.google.android.maps.ZoomHelper.doZoom(ZoomHelper.java:126)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at com.google.android.maps.MapView.doZoom(MapView.java:1459)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at com.google.android.maps.MapView.doZoom(MapView.java:1468)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at com.google.android.maps.MapController.zoomIn(MapController.java:427)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at android.client.ui.showstores.StoreMap.onCreate(StoreMap.java:58)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1123)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2364)
04-15 10:16:51.012: ERROR/AndroidRuntime(528):     ... 11 more

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I found a workaround for that situation.

   int zoomSteps = 2;

   int currentLatitudeSpan = mMapView.getLatitudeSpan();
   int currentLongitudeSpan = mMapView.getLongitudeSpan();

   int zoomedLatitudeSpan = 2 * zoomSteps * currentLatitudeSpan;
   int zoomedLongitudeSpan = 2 * zoomSteps * currentLongitudeSpan;

   mMapController.zoomToSpan(zoomedLatitudeSpan, zoomedLongitudeSpan);'

This snippet zooms the map twice

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Android doesn't set the width and height of views until later, so it'll be 0 in onCreate. I think views specify their sizes in a method called "onLayoutChanged" or something similar, maybe you can override it and do the zoom there.

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You might try to call the zoom methods in onWindowFocusChanged(boolean hasFocus) instead of onCreate or onResume.