Android – How to handle button clicks using the XML onClick within Fragments

androidandroid-fragmentsbuttonxml

Pre-Honeycomb (Android 3), each Activity was registered to handle button clicks via the onClick tag in a Layout's XML:

android:onClick="myClickMethod"

Within that method you can use view.getId() and a switch statement to do the button logic.

With the introduction of Honeycomb I'm breaking these Activities into Fragments which can be reused inside many different Activities. Most of the behavior of the buttons is Activity independent, and I would like the code to reside inside the Fragments file without using the old (pre 1.6) method of registering the OnClickListener for each button.

final Button button = (Button) findViewById(R.id.button_id);
button.setOnClickListener(new View.OnClickListener() {
    public void onClick(View v) {
        // Perform action on click
    }
});

The problem is that when my layout's are inflated it is still the hosting Activity that is receiving the button clicks, not the individual Fragments. Is there a good approach to either

Register the fragment to receive the button clicks?
Pass the click events from the Activity to the fragment they belong to?

Best Answer

I prefer using the following solution for handling onClick events. This works for Activity and Fragments as well.

public class StartFragment extends Fragment implements OnClickListener{

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

        View v = inflater.inflate(R.layout.fragment_start, container, false);

        Button b = (Button) v.findViewById(R.id.StartButton);
        b.setOnClickListener(this);
        return v;
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
        case R.id.StartButton:

            ...

            break;
        }
    }
}

Related Solutions

Android – How to get a Fragment to remove itself, i.e. its equivalent of finish()

While it might not be the best approach the closest equivalent I can think of that works is this with the support/compatibility library

getActivity().getSupportFragmentManager().beginTransaction().remove(this).commit();

getActivity().getFragmentManager().beginTransaction().remove(this).commit();

otherwise.

In addition you can use the backstack and pop it. However keep in mind that the fragment might not be on the backstack (depending on the fragmenttransaction that got it there..) or it might not be the last one that got onto the stack so popping the stack could remove the wrong one...

Android – How to pass values between Fragments

Step 1: To send data from a fragment to an activity

Intent intent = new Intent(getActivity().getBaseContext(),
                           TargetActivity.class);
intent.putExtra("message", message);
getActivity().startActivity(intent);

Step 2: To receive this data in an Activity:

Intent intent = getIntent();
String message = intent.getStringExtra("message");

Step 3: To send data from an activity to another activity, follow the normal approach

Intent intent = new Intent(MainActivity.this,
                           TargetActivity.class);
intent.putExtra("message", message);
startActivity(intent);

Step 4: To receive this data in an activity

  Intent intent = getIntent();
  String message = intent.getStringExtra("message");

Step 5.: From an Activity you can send data to a Fragment with the intent as:

Bundle bundle = new Bundle();
bundle.putString("message", "From Activity");

// Set Fragmentclass Arguments
Fragmentclass fragobj = new Fragmentclass();
fragobj.setArguments(bundle);

And to receive a fragment in the Fragment onCreateView method:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
    String strtext = getArguments().getString("message");

    return inflater.inflate(R.layout.fragment, container, false);
}

Best Answer

Related Solutions

Android – How to get a Fragment to remove itself, i.e. its equivalent of finish()

Android – How to pass values between Fragments

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