您需要在onCreate()方法之外设置一个寄存器调用，此外，您还需要将registerForActivityResult()变量作为片段类的属性。（仅适用于Activity，而不是Fragment！）

Kotlin注册调用示例：

val getContent = registerForActivityResult(GetContent()) { uri: Uri? ->
// Handle the returned Uri

}

JAVA注册调用示例：

// GetContent creates an ActivityResultLauncher<String> to allow you to pass
// in the mime type you'd like to allow the user to select
ActivityResultLauncher<String> mGetContent = registerForActivityResult(new GetContent(),
    new ActivityResultCallback<Uri>() {
        @Override
        public void onActivityResult(Uri uri) {
            // Handle the returned Uri
        }
});

本文档将帮助您理解和实践。干杯：）

如在单独的类中接收活动结果中所述，
Fragment类实现ActivityResultCaller接口，以允许您使用registerForActivityResult（）API
因此，您可以像在Activity中一样使用它：

public class YourFragment extends Fragment {

    private final ActivityResultLauncher<input_type> mActivityResultLauncher = 
            registerForActivityResult(<your_contract>, <your_callback>);

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // just don't register here
        ...
    }

    // call this when needed (e.g. user presses a button)
    private void launchActivityForResult() {
        mActivityResultLauncher.launch(<input>);
    }

}