该程序展示了如何使用地图服务导出地图切片，当导出成功时，导出的地图切片将会被加载到地图中的ArcGISTiledLayer中。(This sample demonstrates how to export tiles from a map service for offline use.Pan and zoom into the desired area, making sure the area you want to take offline is within the red rectangle. Tap on the `Export tiles` button, and this will obtain the default parameters and call `exportTileCacheWithParameters`, which will return a job. The job must be started manually, and once started can be canceled at anytime. Once the job completes successfully, the output tile cache is added as an `ArcGISTiledLayer` to the map.)