安卓开发使用高德地图获取当前定位的5公里范围并显示出来，请用kotlin实现

以下是使用 Kotlin 实现获取当前位置的 5 公里范围内的地点并在地图上显示的示例代码：

1. 添加依赖

在你的 `build.gradle` 文件中添加以下依赖：

dependencies {
    implementation 'com.amap.api:maps:5.5.0'
    implementation 'com.amap.api:location:5.4.0'
}

2. 获取权限

在 `AndroidManifest.xml` 文件中添加以下权限：

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

3. 配置地图

在布局文件中添加 `MapView` 控件：

<com.amap.api.maps.MapView
    android:id="@+id/mapView"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

在 Activity 或 Fragment 中获取 `MapView` 控件并配置地图参数：

class MainActivity : AppCompatActivity(), AMapLocationListener {
    private lateinit var mapView: MapView
    private lateinit var aMap: AMap
    private lateinit var locationClient: AMapLocationClient
    private lateinit var locationOption: AMapLocationClientOption

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        mapView = findViewById(R.id.mapView)
        mapView.onCreate(savedInstanceState)

        aMap = mapView.map
        aMap.uiSettings.isZoomControlsEnabled = true

        locationOption = AMapLocationClientOption()
        locationOption.locationMode = AMapLocationClientOption.AMapLocationMode.Hight_Accuracy
        locationOption.isOnceLocation = true

        locationClient = AMapLocationClient(this)
        locationClient.setLocationOption(locationOption)
        locationClient.setLocationListener(this)

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            if (checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                requestPermissions(arrayOf(Manifest.permission.ACCESS_FINE_LOCATION), 1)
            } else {
                locationClient.startLocation()
            }
        } else {
            locationClient.startLocation()
        }
    }

    override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<String>, grantResults: IntArray) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults)
        if (requestCode == 1 && grantResults.isNotEmpty() && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            locationClient.startLocation()
        }
    }

    override fun onLocationChanged(location: AMapLocation?) {
        if (location != null) {
            if (location.errorCode == 0) {
                val latLng = LatLng(location.latitude, location.longitude)
                val cameraUpdate = CameraUpdateFactory.newLatLngZoom(latLng, 15f)
                aMap.moveCamera(cameraUpdate)

                val search = PoiSearch(this, PoiSearch.Query("", "", location.cityCode))
                search.bound = PoiSearch.SearchBound(latLng, 5000)
                search.setOnPoiSearchListener(object: PoiSearch.OnPoiSearchListener {
                    override fun onPoiSearched(result: PoiResult?, code: Int) {
                        if (code == AMapException.CODE_AMAP_SUCCESS && result != null) {
                            for (poiItem in result.pois) {
                                val markerOptions = MarkerOptions()
                                markerOptions.position(poiItem.latLonPoint.toLatLng())
                                markerOptions.title(poiItem.title)
                                markerOptions.snippet(poiItem.snippet)
                                aMap.addMarker(markerOptions)
                            }
                        }
                    }

                    override fun onPoiItemSearched(p0: PoiItem?, p1: Int) {}
                })
                search.searchPOIAsyn()
            } else {
                Toast.makeText(this, "定位失败", Toast.LENGTH_SHORT).show()
            }
        } else {
            Toast.makeText(this, "定位失败", Toast.LENGTH_SHORT).show()
        }
    }

    override fun onResume() {
        super.onResume()
        mapView.onResume()
    }

    override fun onPause() {
        super.onPause()
        mapView.onPause()
    }

    override fun onSaveInstanceState(outState: Bundle) {
        super.onSaveInstanceState(outState)
        mapView.onSaveInstanceState(outState)
    }

    override fun onDestroy() {
        super.onDestroy()
        mapView.onDestroy()
    }
}

fun LatLonPoint.toLatLng(): LatLng {
    return LatLng(latitude, longitude)
}

在 `onLocationChanged` 回调中，我们使用高德地图的 `PoiSearch` 类来搜索当前位置 5 公里范围内的地点，并在地图上添加标记。注意，这里我们使用了 Kotlin 扩展函数 `LatLonPoint.toLatLng()` 将 `LatLonPoint` 转换为 `LatLng`。

这样，当用户打开应用时，我们会请求定位权限并开始定位。当定位成功后，我们将地图中心移到当前位置，并显示 5 公里范围内的地点。