我有一个AppCompatActivity，其中有3个使用FragmentTabHost的标签。选项卡之一使用LocationServices。我希望获得尽可能流畅的用户体验：
如果LocationService在android系统中处于关闭状态，并且仅当用户选择需要Location的标签时，我才想显示AlertDialog以便用户在系统设置中打开Location。
我有一个辅助程序类，应该可以完成所有这些工作，并且可以在我的应用程序中的其他3个地方使用。在这3个地方，它直接在Activity中起作用，但是在这个地方，它需要在选项卡的Fragment中起作用。
问题是，如果我有一行：
builder.enableAutoManage(activity, 0, this);
然后
builder.build()引发异常：IllegalStateException: Recursive entry to executePendingTransactions知道如何实现目标吗？
以下是一些相关的代码片段：
public class CityPreferences extends AppCompatActivity {
private FragmentTabHost mTabHost;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mTabHost = (FragmentTabHost) findViewById(android.R.id.tabhost);
mTabHost.setup(this, getSupportFragmentManager(), R.id.realtabcontent);
mTabHost.addTab(
mTabHost.newTabSpec("available_cities")
.setIndicator(getString(R.string.tab_all_cities))
, AvailableCityFragment.class, null);
mTabHost.addTab(
mTabHost.newTabSpec("nearby_cities")
.setIndicator(getString(R.string.tab_nearby_cities))
, NearbyCityFragment.class, null);
}
}
在
NearbyCityFragment中，我有以下1行代码：class NearbyCityFragment extends Fragment {
...
LocationServiceHelper.getInstance().startOrDisplayDialog(getActivity());
（我在
onAttach，onStart，onResume中尝试过）这是我的助手类的功能：
public class LocationServiceHelper implements
GoogleApiClient.OnConnectionFailedListener,
GoogleApiClient.ConnectionCallbacks {
public boolean startOrDisplayDialog(@NonNull final FragmentActivity activity) {
final boolean servicesConnected = GooglePlayServicesHelper.checkOrDisplayDialog(activity);
if (servicesConnected) {
final boolean isEnabled = isLocationEnabledInSystem(activity);
if (isEnabled) {
if (null == mGoogleApiClient) {
mContext = activity;
mActivity = activity;
final GoogleApiClient.Builder builder = new GoogleApiClient.Builder(mContext)
.addApi(LocationServices.API)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this);
// the next line seems to cause the problem:
builder.enableAutoManage(activity, 0, this);
mGoogleApiClient = builder
.build();
}
return start();
} else {
final Dialog dialog = getLocationDisabledDialog(activity);
GooglePlayServicesHelper.showDialog(dialog, activity);
}
}
return false;
}
最后是例外：
06-10 10:23:04.831 26725-26725/com.fletech.android.redalert.debug E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.fletech.android.redalert.debug, PID: 26725
java.lang.IllegalStateException: Recursive entry to executePendingTransactions
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1473)
at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:490)
at com.google.android.gms.common.api.g.a(Unknown Source)
at com.google.android.gms.common.api.GoogleApiClient$Builder.gI(Unknown Source)
at com.google.android.gms.common.api.GoogleApiClient$Builder.build(Unknown Source)
at com.fletech.android.redalert.helper.LocationServiceHelper.startOrDisplayDialog(LocationServiceHelper.java:113)
at com.fletech.android.redalert.city.NearbyCityFragment.onAttach(NearbyCityFragment.java:44)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:907)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1138)
at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:740)
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1501)
at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:458)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5257)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
最佳答案
我相信每次启用自动管理器时都必须使用唯一的clientId。从documentation：
clientId-此客户端的非负标识符。在任何给定时间，每个id仅允许一个自动管理的客户端。要重新使用ID，您必须首先在先前的客户端上调用stopAutoManage(FragmentActivity)。