我在尝试获取 fragment 管理器时遇到多个用户的崩溃。知道为什么会崩溃吗？
@Override
public void onNoInternetError() {
Log.i("base", "no internet error!");
final FragmentTransaction ft = getFragmentManager().beginTransaction();
final NoInternetFragment fragment = new NoInternetFragment();
ft.replace(R.id.content_frame, fragment, "noInternetFragment");
ft.addToBackStack(null);
ft.commit();
错误
Fatal Exception: java.lang.NullPointerException: Attempt to invoke virtual method 'android.support.v4.app.p android.support.v4.app.k.a()' on a null object reference
at com.abc.abc.fragments.ABCFragmentBase$1.onNoInternetError(ABCFragmentBase.java:112)
at com.abc.abc.ui.components.NoInternetListener.showNoInternetFragment(NoInternetListener.java:14)
at com.abc.abc.ServerManager.handleFailure(ServerManager.java:1875)
at com.abc.abc.ServerManager.access$100(ServerManager.java:54)
at com.abc.abc.ServerManager$33.onFailure(ServerManager.java:1220)
at com.abc.sdk.JsonObjectRequest.deliverError(JsonObjectRequest.java:70)
at com.android.volley.ExecutorDelivery$ResponseDeliveryRunnable.run(ExecutorDelivery.java:108)
at android.os.Handler.handleCallback(Handler.java:789)
at android.os.Handler.dispatchMessage(Handler.java:98)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6944)
at java.lang.reflect.Method.invoke(Method.java)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)
最佳答案
从您的代码看来，getFragmentManager() 调用返回 null，这可能意味着您的 fragment 尚未通过 onAttach()
你可以为连接错误添加一个标志，然后在onAttach()之后显示相关信息
关于android - 如何修复 'Attempt to invoke virtual method ' android.support.v4.app.p android.support.v4.app.k.a( )' on a null object reference'，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/54434514/