Android Button Click issue

Question

Hi I am having issues understanding why this doesn't work. I have a button and when you click on it it doesn't go to the new activity. I am trying to just have a simple button click that will go to another activity that has a fragment on top of it.

my code for the event click is as follows:

public class PlanMeMainFragment extends Fragment {

    private Button mNewButton, mExistingButton;

        mNewButton = (Button)v.findViewById(R.id.new_event_button);
        mNewButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                ((PlanMeMainActivity) getActivity()).newActivityToLaunch(1);

            }
        });
        return  v;
    }
}

my activity

public class PlanMeMainActivity extends FragmentActivity {

    @Override
    public void onCreate(Bundle savedInstanceState){
      super.onCreate(savedInstanceState);
      setContentView(R.layout.planme_main_fragment);
    }

    public void newActivityToLaunch(int i) {
        Intent myIntent;
        switch(i){
        case 1: myIntent = new Intent(PlanMeMainActivity.this, NewEventSetupActivity.class);
        }

        startActivity(myIntent);
    }
}

I listed the manifest as such:

<activity
    android:name="com.pctoolman.planme.app.PlanMeMainActivity"
    android:label="@string/app_name" >
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
</activity>
<activity
    android:name="com.pctoolman.planme.app.NewEventSetupActivity"
    android:label="@string/setup">
</activity>

Answer 1

You should create an interface in your Fragment class and implement that interface in the activity in which your fragment is inflated. That way when the button is clicked in your activity, the interface method will be called in the onClick method in your fragment and will execute the code of that interface method in your activity. In this case your method will launch an intent.

Step 1: create the interface within your fragment class

public interface OnFragmentInteractionListener {
    public void onFragmentInteraction();
}

Step 2: Create a variable for the interface in your fragment class

private OnFragmentInteractionListener mListener;

Step 3: Initialize the listener by overriding the onAttach method and making sure the listener is implemented in the fragments activity

@Override
public void onAttach(Activity activity) {
    super.onAttach(activity);
    try {
        mListener = (OnFragmentInteractionListener) activity;
    } catch (ClassCastException e) {
        throw new ClassCastException(activity.toString()
                + " must implement OnFragmentInteractionListener");
    }
}

Step 4: Handle the onClick method in your fragment class

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View v = inflater.inflate(R.layout.planme_main_fragment, container, false);

    mNewButton = (Button)v.findViewById(R.id.new_event_button);
    mNewButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            mListener.onFragmentInteraction(); // executes this method in the activity
        }
    });
    return  v;
}

Step 5: Implement the interface in your activity

public MainActivity extends Activity implements 
          PlanMeMainFragment.OnFragmentInteractionListener

Override the interface method in your activity

public void onFragmentInteraction(){
    Intent intent = new Intent(this, NewEventSetupActivity.class);
    startActivity(intent);
}

Step 7: detach the listener in your fragment class

@Override
public void onDetach() {
    super.onDetach();
    mListener = null;
}

See the Android Training lesson Communicating with Other Fragments for more information.

Answer 2

Try changing this :

<activity 
   android:name="com.pctoolman.planme.app.NewEventSetupActivity"
   android:label="@string/setup">
</activity>

to this:

<activity
    android:name="com.pctoolman.planme.app.NewEventSetupActivity"
    android:label="@string/setup">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.DEFAULT" />
    </intent-filter>
</activity>

Answer 3

Try something else, answer's @vdisawar gives me the idea:

in your Fragment:

// in your onClick method  
// call a method in your Activity 
((PlanMeMainActivity) getActivity()).newActivityToLaunch(); 

in your FragmentActivity:

// newActivityToLaunch method  
public void newActivityToLaunch() {
    Intent myIntent = new Intent(PlanMeMainActivity.this, NewEventSetupActivity.class);
    startActivity(myIntent);
}  

With this tip, you will able to call different activities with the same method from different fragment, let see a simple example:

FragmentA wants to launch Activity1:

// call a method with an integer 
((MainActivity) getActivity()).newActivityToLaunch(1);  

in another fragment (FragmentB), this one wants to launch Activity2:

// call the same method with another integer 
((MainActivity) getActivity()).newActivityToLaunch(2);  

then in your FragmentActivity, the method is:

// newActivityToLaunch method  
public void newActivityToLaunch(int i) {
    // create a general intent
    Intent myIntent = null;
    // switch i received from fragments
    switch(i) {
        // received from FragmentA
        case 1: myIntent = new Intent(MainActivity.this, Activity1.class);
        // received from FragmentB
        case 2: myIntent = new Intent(MainActivity.this, Activity2.class);
    }
    // start the activity
    startActivity(myIntent);
}  

Hope this helps.