getArguments()返回null因为“它没有得到任何东西”

试试这段代码来处理这种情况

if(getArguments()!=null)
{
int myInt = getArguments().getInt(key, defaultValue);
}

使用片段传递数据的完整代码

Fragment fragment = new Fragment(); // replace your custom fragment class 
Bundle bundle = new Bundle();
FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
                bundle.putString("key","value"); // use as per your need
                fragment.setArguments(bundle);
                fragmentTransaction.addToBackStack(null);
                fragmentTransaction.replace(viewID,fragment);
                fragmentTransaction.commit();

在自定义片段类中

Bundle mBundle = new Bundle();
mBundle = getArguments();
mBundle.getString(key);  // key must be same which was given in first fragment

只是扩展一下前面的答案——它可以帮助到一些人。如果你的getArguments()返回null，把它放在onCreate()方法，而不是你的片段的构造函数:

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    int index = getArguments().getInt("index");
}

如果你正在使用kotlin，那么你可以传递bundle as

val fragment = YourFragment()
val bundle = Bundle().apply {
    putInt("someInt", 5)
    putString("someString", "Hello")
}
fragment.arguments = bundle

在YourFragment的onCreate中获取这些值

this.arguments?.let {
    val someInt    = it.getInt("someInt", someDefaultInt)
    val someString = it.getString("someString", someDefaultString)
}

getArguments()返回null因为“它没有得到任何东西”

试试这段代码来处理这种情况

if(getArguments()!=null)
{
int myInt = getArguments().getInt(key, defaultValue);
}

来自活动课:

使用bundle参数将数据发送到片段并加载片段

   Fragment fragment = new myFragment();
   Bundle bundle = new Bundle();
   bundle.putString("pName", personName);
   bundle.putString("pEmail", personEmail);
   bundle.putString("pId", personId);
   fragment.setArguments(bundle);

   getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container,
                    fragment).commit();

从myFragment类:

从bundle中获取参数并将它们设置为xml

    Bundle arguments = getArguments();
    String personName = arguments.getString("pName");
    String personEmail = arguments.getString("pEmail");
    String personId = arguments.getString("pId");

    nameTV = v.findViewById(R.id.name);
    emailTV = v.findViewById(R.id.email);
    idTV = v.findViewById(R.id.id);

    nameTV.setText("Name: "+ personName);
    emailTV.setText("Email: "+ personEmail);
    idTV.setText("ID: "+ personId);