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I am experimenting with KML and GeoJson for Android and I'm trying to show certain layers but not others. KML doesn't seem to allow for the flexibility that GeoJson does.

GeoJson allows me to to add/remove features based on certain criteria. For instance, I may want to show a base zone (Polygon) always, but only show other zones at certain zoom levels due to lag of having many polygons on the screen.

What I am currently trying to do with GeoJson is to highlight the inverse of a region. A good example of this can be seen in the car2go app

Blake
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2 Answers2

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I figured out the answer from another post here

// World boundary. Can't make -90 otherwise rendering error
val polygon = PolygonOptions().add(
        LatLng(-89.999999999999, -180.0),
        LatLng(89.99999999999, -180.0),
        LatLng(89.99999999999, 179.99999999),
        LatLng(-89.99999999999, 179.99999999),
        LatLng(-89.99999999999, 0.0))

// Test hole of Europe
polygon.addHole(listOf(
        LatLng(29.68224948021748, -23.676965750000022),
        LatLng(29.68224948021748, 44.87772174999998),
        LatLng(71.82725578445813, 44.87772174999998),
        LatLng(71.82725578445813, -23.676965750000022)))

polygon.fillColor(Color.argb(75, 125, 125, 220))
polygon.strokeColor(Color.argb(205, 125, 125, 220))
polygon.strokeWidth(2.0f)

map?.addPolygon(polygon)
Blake
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0

Here a code snippet for GeoJson, to add a world rectangle to the coordinates. That will cut out/invert/reverse the polygon in geoJson.

geoJson.geometry.coordinates[0].unshift([[180, -90], [180, 90], [-180, 90], [-180, -90]]);
Falk Brückner
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