Question

我知道有很多关于此的问题，但他们都没有解决我的问题我想将一个字符串变量从一个片段传递给另一个片段，这是我做的代码。但我收到错误（我会显示错误）

从我做的第一个片段

Desc_1 ldf = new Desc_1 ();
Bundle args = new Bundle();
args.putString("YourKey", "YourValue");
ldf.setArguments(args);
getFragmentManager().beginTransaction().add(R.id.frame, ldf).commit();

和传入的第二个片段我喜欢

public class Desc_1 extends Fragment {

    public Desc_1() {
        // Required empty public constructor
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {

        View rootview=inflater.inflate(R.layout.fragment_desc_1,container,false);

        String value = getArguments().getString("YourKey");

        Toast.makeText(getActivity(), value,
                Toast.LENGTH_LONG).show();

        return rootview;

    }
}

我收到错误

07-27 20:31:06.386 26816-26816/com.example.jaison.newsclient E/AndroidRuntime: FATAL EXCEPTION: main
   Process: com.example.jaison.newsclient, PID: 26816
   java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.os.Bundle.getString(java.lang.String)' on a null object reference
       at layout.Desc_1.onCreateView(Desc_1.java:34)
       at android.support.v4.app.Fragment.performCreateView(Fragment.java:2239)
       at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1332)
       at android.support.v4.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1574)
       at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1641)
       at android.support.v4.app.BackStackRecord.executeOps(BackStackRecord.java:794)
       at android.support.v4.app.FragmentManagerImpl.executeOps(FragmentManager.java:2415)
       at android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2200)
       at android.support.v4.app.FragmentManagerImpl.optimizeAndExecuteOps(FragmentManager.java:2153)
       at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:2063)
       at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:725)
       at android.os.Handler.handleCallback(Handler.java:815)
       at android.os.Handler.dispatchMessage(Handler.java:104)
       at android.os.Looper.loop(Looper.java:207)
       at android.app.ActivityThread.main(ActivityThread.java:5769)
       at java.lang.reflect.Method.invoke(Native Method)
       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:861)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:751)

Answer 1

检查片段中getArguments()是否为空，然后在花括号内添加代码

示例：

Bundle bundle_arguments = getArguments(); if(bundle_arguments != null) { // your code }

Answer 2

试试这个：

Bundle bundle = getArguments();
if(bundle != null)
    String value = bundle.getString("YourKey");

Answer 3

请检查此答案是否在片段之间传递值

https://stackoverflow.com/a/27626004/5065318

无法将字符串值从一个片段传递到另一个片段

3 个答案: