我想从文件中加载坐标，并在异步任务中向我的地图添加形状。但我得到错误，我不知道为什么。这是我的代码：
private class shpLoading extends AsyncTask<GoogleMap, Void, String> {
ProgressDialog dialog;
@Override
protected String doInBackground(GoogleMap... params) {
ShpReader shpRead = new ShpReader();
GoogleMap map = params[0];
try {
shpRead.reading();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (InvalidShapeFileException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
for(LatLng a : shpRead.points())
map.addMarker(new MarkerOptions()
.position(a)
.draggable(false));
int i = 0;
for(List<LatLng> a: shpRead.lines()){
map.addPolyline(new PolylineOptions()
.addAll(a)
.width(3)
.color(Color.RED));
}
for(List<LatLng> a: shpRead.polygons()){
map.addPolygon(new PolygonOptions()
.addAll(a)
.strokeWidth(3)
.strokeColor(Color.RED)
.fillColor(0x3F00FF00));
}
return "Done";
}
@Override
protected void onPreExecute() {
dialog = new ProgressDialog(Measuring.this);
dialog.setMessage("Kraunama...");
dialog.setIndeterminate(true);
dialog.setCancelable(false);
dialog.show();
}
@Override
protected void onProgressUpdate(Void... values) {
}
@Override
protected void onPostExecute(String result) {
dialog.dismiss();
}
}
这就是我执行代码的方式：
shpLoading load = new shpLoading();
load.execute(mMap);
mMap是GoogleMap变量。如果我将所有doInBackground代码添加到onPostExecute方法并将变量map更改为全局mMap eveything正在运行，但我想在后台执行此任务并显示加载对话框同时。
这是我的LogCat：
08-26 11:10:52.368: E/AndroidRuntime(11099): FATAL EXCEPTION:
AsyncTask #1
08-26 11:10:52.368: E/AndroidRuntime(11099):
java.lang.RuntimeException: An error occured while executing
doInBackground()
08-26 11:10:52.368: E/AndroidRuntime(11099): at
android.os.AsyncTask$3.done(AsyncTask.java:299) 08-26 11:10:52.368:
E/AndroidRuntime(11099): at
java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
08-26 11:10:52.368: E/AndroidRuntime(11099): at
java.util.concurrent.FutureTask.setException(FutureTask.java:124)
08-26 11:10:52.368: E/AndroidRuntime(11099): at
java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
08-26 11:10:52.368: E/AndroidRuntime(11099): at
java.util.concurrent.FutureTask.run(FutureTask.java:137) 08-26
11:10:52.368: E/AndroidRuntime(11099): at
android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230) 08-26
11:10:52.368: E/AndroidRuntime(11099): at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
08-26 11:10:52.368: E/AndroidRuntime(11099): at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
08-26 11:10:52.368: E/AndroidRuntime(11099): at
java.lang.Thread.run(Thread.java:856) 08-26 11:10:52.368:
E/AndroidRuntime(11099): Caused by: java.lang.IllegalStateException:
Not on the main thread 08-26 11:10:52.368: E/AndroidRuntime(11099):
at maps.ar.p.b(Unknown Source) 08-26 11:10:52.368:
E/AndroidRuntime(11099): at maps.al.g.b(Unknown Source) 08-26
11:10:52.368: E/AndroidRuntime(11099): at maps.ag.an.a(Unknown
Source) 08-26 11:10:52.368: E/AndroidRuntime(11099): at
bkw.onTransact(SourceFile:137) 08-26 11:10:52.368:
E/AndroidRuntime(11099): at
android.os.Binder.transact(Binder.java:326) 08-26 11:10:52.368:
E/AndroidRuntime(11099): at
com.google.android.gms.maps.internal.IGoogleMapDelegate$a$a.addPolyline(Unknown
Source) 08-26 11:10:52.368: E/AndroidRuntime(11099): at
com.google.android.gms.maps.GoogleMap.addPolyline(Unknown Source)
08-26 11:10:52.368: E/AndroidRuntime(11099): at
com.es.map.Measuring$shpLoading.doInBackground(Measuring.java:1165)
08-26 11:10:52.368: E/AndroidRuntime(11099): at
com.es.map.Measuring$shpLoading.doInBackground(Measuring.java:1) 08-26
11:10:52.368: E/AndroidRuntime(11099): at
android.os.AsyncTask$2.call(AsyncTask.java:287) 08-26 11:10:52.368:
E/AndroidRuntime(11099): at
java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
08-26 11:10:52.368: E/AndroidRuntime(11099): ... 5 more 08-26
11:11:00.453: E/WindowManager(11099): Activity com.es.map.Measuring
has leaked window
com.android.internal.policy.impl.PhoneWindow$DecorView@42229e30 that
was originally added here 08-26 11:11:00.453: E/WindowManager(11099):
android.view.WindowLeaked: Activity com.es.map.Measuring has leaked
window com.android.internal.policy.impl.PhoneWindow$DecorView@42229e30
that was originally added here 08-26 11:11:00.453:
E/WindowManager(11099): at
android.view.ViewRootImpl.<init(ViewRootImpl.java:403) 08-26
11:11:00.453: E/WindowManager(11099): at
android.view.WindowManagerImpl.addView(WindowManagerImpl.java:311)
08-26 11:11:00.453: E/WindowManager(11099): at
android.view.WindowManagerImpl.addView(WindowManagerImpl.java:224)
08-26 11:11:00.453: E/WindowManager(11099): at
android.view.WindowManagerImpl$CompatModeWrapper.addView(WindowManagerImpl.java:149)
08-26 11:11:00.453: E/WindowManager(11099): at
android.view.Window$LocalWindowManager.addView(Window.java:554) 08-26
11:11:00.453: E/WindowManager(11099): at
android.app.Dialog.show(Dialog.java:277) 08-26 11:11:00.453:
E/WindowManager(11099): at
com.es.map.Measuring$shpLoading.onPreExecute(Measuring.java:1195)
08-26 11:11:00.453: E/WindowManager(11099): at
android.os.AsyncTask.executeOnExecutor(AsyncTask.java:586) 08-26
11:11:00.453: E/WindowManager(11099): at
android.os.AsyncTask.execute(AsyncTask.java:534) 08-26 11:11:00.453:
E/WindowManager(11099): at
com.es.map.Measuring.onOptionsItemSelected(Measuring.java:566) 08-26
11:11:00.453: E/WindowManager(11099): at
android.app.Activity.onMenuItemSelected(Activity.java:2629) 08-26
11:11:00.453: E/WindowManager(11099): at
android.support.v4.app.FragmentActivity.onMenuItemSelected(FragmentActivity.java:366)
08-26 11:11:00.453: E/WindowManager(11099): at
com.android.internal.policy.impl.PhoneWindow.onMenuItemSelected(PhoneWindow.java)
08-26 11:11:00.453: E/WindowManager(11099): at
com.android.internal.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:735)
08-26 11:11:00.453: E/WindowManager(11099): at
com.android.internal.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:149)
08-26 11:11:00.453: E/WindowManager(11099): at
com.android.internal.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:874)
08-26 11:11:00.453: E/WindowManager(11099): at
com.android.internal.view.menu.IconMenuView.invokeItem(IconMenuView.java:468)
08-26 11:11:00.453: E/WindowManager(11099): at
com.android.internal.view.menu.IconMenuItemView.performClick(IconMenuItemView.java:126)
08-26 11:11:00.453: E/WindowManager(11099): at
android.view.View$PerformClick.run(View.java:17298) 08-26
11:11:00.453: E/WindowManager(11099): at
android.os.Handler.handleCallback(Handler.java:615) 08-26
11:11:00.453: E/WindowManager(11099): at
android.os.Handler.dispatchMessage(Handler.java:92) 08-26
11:11:00.453: E/WindowManager(11099): at
android.os.Looper.loop(Looper.java:137) 08-26 11:11:00.453:
E/WindowManager(11099): at
android.app.ActivityThread.main(ActivityThread.java:4921) 08-26
11:11:00.453: E/WindowManager(11099): at
java.lang.reflect.Method.invokeNative(Native Method) 08-26
11:11:00.453: E/WindowManager(11099): at
java.lang.reflect.Method.invoke(Method.java:511) 08-26 11:11:00.453:
E/WindowManager(11099): at
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1038)
08-26 11:11:00.453: E/WindowManager(11099): at
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:805) 08-26
11:11:00.453: E/WindowManager(11099): at
dalvik.system.NativeStart.main(Native Method)
也许这不是从文件加载坐标并将它们添加到地图的好方法？也许有更好的方法来做到这一点？
答案 0 :(得分：3)
很抱歉，您无法从后台线程更改UI组件，您必须在UIThread中编写地图操作。
您现有代码中的解决方案如下：
private Handler mHandler = new Handler();
private class shpLoading extends AsyncTask<GoogleMap, Void, String> {
ProgressDialog dialog;
@Override
protected String doInBackground(GoogleMap... params) {
ShpReader shpRead = new ShpReader();
GoogleMap map = params[0];
try {
shpRead.reading();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (InvalidShapeFileException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
mHandler.post(new Runnable() {
public void run() {
for(LatLng a : shpRead.points())
map.addMarker(new MarkerOptions()
.position(a)
.draggable(false));
int i = 0;
for(List<LatLng> a: shpRead.lines()){
map.addPolyline(new PolylineOptions()
.addAll(a)
.width(3)
.color(Color.RED));
}
for(List<LatLng> a: shpRead.polygons()){
map.addPolygon(new PolygonOptions()
.addAll(a)
.strokeWidth(3)
.strokeColor(Color.RED)
.fillColor(0x3F00FF00));
}
}
});
return "Done";
}
@Override
protected void onPreExecute() {
dialog = new ProgressDialog(Measuring.this);
dialog.setMessage("Kraunama...");
dialog.setIndeterminate(true);
dialog.setCancelable(false);
dialog.show();
}
@Override
protected void onProgressUpdate(Void... values) {
}
@Override
protected void onPostExecute(String result) {
dialog.dismiss();
}
}
答案 1 :(得分：0)
你不能在后台进行ui操作，map.add应该在进度更改中发生...只需调用报告进度并在那里进行地图绘制。