如何在 Fragment 中使用方法 onNewIntent(Intent intent)？

Question

I'm trying to use NFC Hardware from my device. But, the problem is that when I register the Activity to receive the Intent:

PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, new Intent(this, getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0);

I receive the result in an Activity instead of a Fragment. Is there a way to handle this result inside a Fragment?

Thanks in advance!

Answer 1

onNewIntent belongs to Activity so you cannot have it in your fragment. What you can do is pass the data to your fragment when it arrives in onNewIntent provided you have the reference to the fragment.

Fragment fragment;  
@Override
protected void onNewIntent(Intent intent) {
    super.onNewIntent(intent);

    // Check if the fragment is an instance of the right fragment
    if (fragment instanceof MyNFCFragment) {
        MyNFCFragment my = (MyNFCFragment) fragment;
        // Pass intent or its data to the fragment's method
        my.processNFC(intent.getStringExtra());
    }

}

Answer 2

I fixed my issue the following way:

in MyActivity.java

@Override
protected void onNewIntent(Intent intent) {
    super.onNewIntent(intent);
    setIntent(intent);
}

in MyFragment.java

@Override
public void onStart() {
    super.onStart();
    if (getActivity() != null && getActivity().getIntent().hasExtra(...)) {
        // do whatever needed
    }
}

Answer 3

Using LiveData :

Repository:

class IntentRepo  {
    private val _intent = MutableLiveData<Intent>()

    val get: LiveData<Intent> = Transformations.map(_intent) { it!! }

    fun set(intent: Intent) { _intent.value = intent }
}

Activity ViewModel:

class MainViewModel(intentRepo: IntentRepo) : ViewModel() {
    val intent = intentRepo
}

Activity

override fun onNewIntent(intent: Intent?) {
    super.onNewIntent(intent)
    viewModel.intent.set(intent)
}

Fragment

viewModel.intent.get.observe(viewLifecycleOwner, {
    // Your intent: $it
})

Answer 4

We handled the call in a more dynamic way to support any fragment, by having in the Activity something like:

// ...

public class ActivityMain extends AppCompatActivity {

    // ...

    @Override
    protected void onNewIntent(Intent intent) {
        super.onNewIntent(intent);
        Fragment fragment = getFragment();
        if (fragment != null) {
            try {
                Method method = fragment.getClass().getMethod("onNewIntent", Intent.class);
                method.invoke(fragment, intent);
            } catch (NoSuchMethodException ignored) {
            } catch (IllegalAccessException | InvocationTargetException e) {
                Log.e(TAG, "Failed to call onNewIntent method for class: " + fragment.getClass().getSimpleName());
            }
        }
    }

    public Fragment getFragment() {
        //if (BuildConfig.UI_NAVIGATION_DRAWER) {
            FragmentManager manager = this.getSupportFragmentManager();
            manager.executePendingTransactions();
            return manager.findFragmentById(R.id.my_main_content);
        //} else {
            // TODO: Handle view pager.
        //}
    }
}

And later in any Fragment implementation required:

  @SuppressWarnings("unused")
  public void onNewIntent(Intent intent) {
    Log.i(TAG, "onNewIntent: " + intent);
  }