More efficient map overlay on Android

Question

In my application, I draw bus routes on top of MapView . Routes have from a few dozen to several hundred GPS coordinates that describe the route that the bus takes.

The problem I am facing is that when I cross out all of these lines, panning / zooming is MapViewincredibly slow (even pressing the back button takes a minute).

I'm not sure how appropriate it is, but I added the debugging code, and then checked the logcat output, and MapViewrepeatedly called the draw() Overlay method , whether something changed or not. This happens several times per second and causes a huge amount of garbage collection (2-3 MB per second).

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Answer 1

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Answer 2

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