我正在为Android创建GPS应用程序，该应用程序将用户从其当前位置引导至2个预定义位置之一。我从Google服务器下载路线，然后暂时将其存储在JSONObject中。如果方向变得太长或太复杂，则应用程序会因内存不足错误而崩溃。我想我需要使JSON对象可流化或将其更改为JSON阅读器，但我已经搜索了答案，但我不了解如何实现。任何人都可以使用下面的代码提供示例吗？谢谢！
public DrivingDirection(JSONObject response) {
try {
JSONArray jsonArray = response.getJSONArray(TAG_ROUTES);
JSONObject jsonObject = jsonArray.getJSONObject(0);
summary = jsonObject.getString(TAG_SUMMARY);
copyrights = jsonObject.getString(TAG_COPYRIGHTS);
overviewPolyline = decodePolyline(jsonObject.getJSONObject(TAG_OVERVIEW_POLYLINE).getString("points"));
warnings = jsonObject.getJSONArray(TAG_WARNINGS);
waypointOrder = jsonObject.getJSONArray(TAG_WAYPOINT_ORDER);
JSONObject bounds = jsonObject.getJSONObject(TAG_BOUNDS);
boundNorthEast = interpretLatLng(bounds.getJSONObject(TAG_BOUND_NORTH_EAST));
boundSouthWest = interpretLatLng(bounds.getJSONObject(TAG_BOUND_SOUTH_WEST));
JSONArray legs = jsonObject.getJSONArray(TAG_LEGS);
directionLegs = new ArrayList<DirectionLeg>(legs.length());
for (int i=0; i<legs.length(); i++){
directionLegs.add(new DirectionLeg(legs.getJSONObject(i)));
}
directions = response.toString();
} catch (JSONException e) {
// Log.e(Debug.TAG, e.getMessage(), e);
}
}
嗨x-code，这是LogCat关于错误的输出，谢谢。
08-09 16:32:26.560: D/AndroidRuntime(2258): Shutting down VM
08-09 16:32:26.564: W/dalvikvm(2258): threadid=1: thread exiting with uncaught exception (group=0xa61f8908)
08-09 16:32:26.564: E/AndroidRuntime(2258): FATAL EXCEPTION: main
08-09 16:32:26.564: E/AndroidRuntime(2258): java.lang.IllegalStateException: Could not execute method of the activity
08-09 16:32:26.564: E/AndroidRuntime(2258): at android.view.View$1.onClick(View.java:3599)
08-09 16:32:26.564: E/AndroidRuntime(2258): at android.view.View.performClick(View.java:4204)
08-09 16:32:26.564: E/AndroidRuntime(2258): at android.view.View$PerformClick.run(View.java:17355)
08-09 16:32:26.564: E/AndroidRuntime(2258): at android.os.Handler.handleCallback(Handler.java:725)
08-09 16:32:26.564: E/AndroidRuntime(2258): at android.os.Handler.dispatchMessage(Handler.java:92)
08-09 16:32:26.564: E/AndroidRuntime(2258): at android.os.Looper.loop(Looper.java:137)
08-09 16:32:26.564: E/AndroidRuntime(2258): at android.app.ActivityThread.main(ActivityThread.java:5041)
08-09 16:32:26.564: E/AndroidRuntime(2258): at java.lang.reflect.Method.invokeNative(Native Method)
08-09 16:32:26.564: E/AndroidRuntime(2258): at java.lang.reflect.Method.invoke(Method.java:511)
08-09 16:32:26.564: E/AndroidRuntime(2258): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
08-09 16:32:26.564: E/AndroidRuntime(2258): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
08-09 16:32:26.564: E/AndroidRuntime(2258): at dalvik.system.NativeStart.main(Native Method)
08-09 16:32:26.564: E/AndroidRuntime(2258): Caused by: java.lang.reflect.InvocationTargetException
08-09 16:32:26.564: E/AndroidRuntime(2258): at java.lang.reflect.Method.invokeNative(Native Method)
08-09 16:32:26.564: E/AndroidRuntime(2258): at java.lang.reflect.Method.invoke(Method.java:511)
08-09 16:32:26.564: E/AndroidRuntime(2258): at android.view.View$1.onClick(View.java:3594)
08-09 16:32:26.564: E/AndroidRuntime(2258): ... 11 more
08-09 16:32:26.564: E/AndroidRuntime(2258): Caused by: java.lang.OutOfMemoryError
08-09 16:32:26.564: E/AndroidRuntime(2258): at oat.a(Unknown Source)
08-09 16:32:26.564: E/AndroidRuntime(2258): at ova.j(Unknown Source)
08-09 16:32:26.564: E/AndroidRuntime(2258): at oux.b(Unknown Source)
08-09 16:32:26.564: E/AndroidRuntime(2258): at oux.a(Unknown Source)
08-09 16:32:26.564: E/AndroidRuntime(2258): at oyf.a(Unknown Source)
08-09 16:32:26.564: E/AndroidRuntime(2258): at grl.onTransact(SourceFile:137)
08-09 16:32:26.564: E/AndroidRuntime(2258): at android.os.Binder.transact(Binder.java:310)
08-09 16:32:26.564: E/AndroidRuntime(2258): at com.google.android.gms.maps.internal.IGoogleMapDelegate$a$a.addPolyline(Unknown Source)
08-09 16:32:26.564: E/AndroidRuntime(2258): at com.google.android.gms.maps.GoogleMap.addPolyline(Unknown Source)
08-09 16:32:26.564: E/AndroidRuntime(2258): at com.L00081183.mygpstool.MainActivity.onClick_GetDirections(MainActivity.java:177)
08-09 16:32:26.564: E/AndroidRuntime(2258): ... 14 more
08-09 16:32:26.816: I/dalvikvm-heap(2258): Clamp target GC heap from 257.458MB to 256.000MB
08-09 16:32:26.816: D/dalvikvm(2258): GC_CONCURRENT freed 446K, 1% free 261480K/262144K, paused 1ms+10ms, total 252ms
这是我调用getDirections方法的地方
public void onClick_GetDirections(View v) {
LocationManager lm;
lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
Location lastKnownLoc = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
double longTemp = (double)(lastKnownLoc.getLongitude());
double latTemp = (double)(lastKnownLoc.getLatitude());
LatLng Start = new LatLng(latTemp, longTemp);
LatLng start = new LatLng(55.1082, -6.69342);
LatLng end = new LatLng(54.509373, -8.180787);
DirectionAPI directionAPI = new DirectionAPI(Start, LOCATION_LETTERKENNY);
GoogleResponse googleResponse = directionAPI.execute();
if (googleResponse.isOk()){
DrivingDirection drivingDirection = new DrivingDirection(googleResponse.getJsonObject());
ArrayList<LatLng> polyline = drivingDirection.getTotalPolyline();
//PolylineOptions rectLine = new PolylineOptions().width(3).color(Color.RED);
PolylineOptions rectline = new PolylineOptions().width(5).color(Color.BLUE).geodesic(true);
for (int z = 0; z < polyline.size(); z++) {
LatLng point = polyline.get(z);
rectline.add(point);
GPSToolMap.addPolyline(rectline);
}
//GP
}
}