How to Handle onClick in Fragments

Question

This is my first try on Fragments and I'm not able to handle android:onClick

I have a button inside my fragment XML like this

    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/save_keywords_button"
        android:id="@+id/save_keywords"
        android:layout_marginTop="340dp"
        android:background="#FF2E7D32"
        android:textColor="#FFFFFF"
        android:typeface="normal"
        android:onClick="myLogic" />

I searched many results and can't get the exact solution to handle the onClick event.

My question is, How can I get the ID of my button and write the myLogic method. FindViewById() is not working in fragments and where should I write the method? in fragment or in my activity?

Visit this link https://developer.android.com/tools/data-binding/guide.html#binding_events — USKMobility, Feb 21 '16 at 08:34

score 29 · Accepted Answer · edited May 23 '17 at 12:34

Better approach would be implementing OnClickListener to your fragment class and overriding onCreateView in your fragment where you assign the listener to your button.

By putting onClick attribute in your XML layout, your activity on load will look for the element in the activity, not in the fragment. This will throw exception.

I would suggest reading some fragment-activity hierarchy to understand when is it possible to access elements in your fragment.

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.save_keywords);
    b.setOnClickListener(this);
    return v;
}

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

        ...

        break;
    }
}
}

Reference from: here

score 3 · Answer 2 · edited May 23 '17 at 11:46

3

android:onClick="myLogic" will not call the method myLogic inside the fragment. Use OnClickListener instead to handle this type of events.

See these below references

Best way to implement View.OnClickListener in android

http://developer.android.com/reference/android/view/View.OnClickListener.html

edited May 23 '17 at 11:46

Community

1
1

answered Feb 21 '16 at 08:35

oldcode

1,669
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score 1 · Answer 3 · answered Feb 21 '16 at 08:40

1

If you need to get view in fragmen you can do this getView().findViewById(R.id.foo); only after onCreateView() has been called. And if you specify onClick in xml, you do not need to code any linking to that method in your program, just implement that method in your activity.

answered Feb 21 '16 at 08:40

callOfCode

893
8
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As you said, I wrote a method "public void myLogic(View v)" in main Activity but I' getting this error when I click the button java.lang.IllegalStateException: Could not find method myLogic(View) in a parent or ancestor Context for android:onClick attribute defined on view class android.support.v7.widget.AppCompatButton with id 'save_keywords' – Uday Feb 21 '16 at 08:49
@Uday we would need code of your fragment and activity to see what is wrong. It is a good idea to set onclick listener manually. If you will misspell your method name in code, it will not be called. – callOfCode Feb 21 '16 at 09:06

score 0 · Answer 4 · edited Feb 22 '16 at 05:49

0

Try to add method

public void myLogic(View v)

edited Feb 22 '16 at 05:49

Jaffer Wilson

7,029
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answered Feb 21 '16 at 08:32

Nir Horovitz

37
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1

Added it in my mainActivity and got this error on hitting the button Could not find method myLogic(View) in a parent or ancestor Context for android:onClick attribute defined on view class android.support.v7.widget.AppCompatButton with id 'save_keywords' – Uday Feb 21 '16 at 08:52

How to Handle onClick in Fragments

4 Answers4