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findViewById in Fragment

I am trying to create an ImageView in a Fragment which will refer to the ImageView element which I have created in the XML for the Fragment. However, the findViewById<\/code> method only works if I extend an Activity class. Is there anyway of which I can use it in Fragment as well?

public class TestClass extends Fragment {
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        ImageView imageView = (ImageView)findViewById(R.id.my_image);
        return inflater.inflate(R.layout.testclassfragment, container, false);
    }
}

Use getView() or the View parameter from implementing the onViewCreated method. It returns the root view for the fragment (the one returned by onCreateView() method) . With this you can call findViewById() .

@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
    ImageView imageView = (ImageView) getView().findViewById(R.id.foo);
    // or  (ImageView) view.findViewById(R.id.foo); 

As getView() works only after onCreateView() , you can't use it inside onCreate() or onCreateView() methods of the fragment .

You need to inflate the Fragment's view and call findViewById() on the View it returns.

public View onCreateView(LayoutInflater inflater, 
                         ViewGroup container, 
                         Bundle savedInstanceState) {
     View view = inflater.inflate(R.layout.testclassfragment, container, false);
     ImageView imageView = (ImageView) view.findViewById(R.id.my_image);
     return view;
}

Inside Fragment class you will get onViewCreated() override method where you should always initialize your views as in this method you get view object using which you can find your views like :

@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    view.findViewById(R.id.yourId).setOnClickListener(this);

    // or
    getActivity().findViewById(R.id.yourId).setOnClickListener(this);
}

Always remember in case of Fragment that onViewCreated() method will not called automatically if you are returning null or super.onCreateView() from onCreateView() method. It will be called by default in case of ListFragment as ListFragment return FrameLayout by default.

Note: you can get the fragment view anywhere in the class by using getView() once onCreateView() has been executed successfully. ie

getView().findViewById("your view id");

I realise this is an old question, but the prevailing answer leaves something to be desired.

The question is not clear what is required of imageView - are we passing it back as the view, or merely saving a reference for later?

Either way, if the ImageView is coming from the inflated layout, the correct way to do this would be:

public class TestClass extends Fragment {
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View v = inflater.inflate(R.layout.testclassfragment, container, false);
        ImageView imageView = (ImageView)v.findViewById(R.id.my_image);
        return v;
    }
}

Get first the fragment view and then get from this view your ImageView.

public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.testclassfragment, container, false);
    ImageView imageView = (ImageView) view.findViewById(R.id.my_image);
    return view;
}

You could also do it in the onActivityCreated Method.

public void onActivityCreated(Bundle savedInstanceState) { 
      super.onActivityCreated(savedInstanceState);
}

Like they do here: http://developer.android.com/reference/android/app/Fragment.html (deprecated in API level 28)

getView().findViewById(R.id.foo);

and

getActivity().findViewById(R.id.foo);

are possible.

Inside Fragment class we get onViewCreated() override method where we should always initialize our views because in this method we get view object. Using this object we can find our views like below:

class MyFragment extends Fragment {
    private ImageView imageView;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        return inflater.inflate(R.layout.my_fragment_layout, container, false);
    }

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);

        //initialize your view here for use view.findViewById("your view id")
        imageView = (ImageView) view.findViewById(R.id.my_image);
    }
}

getView()将给出根视图

View v = getView().findViewByID(R.id.x); 

You can override onViewCreated() which is called right after all views had been inflated. It's the right place to fill in your Fragment's member View variables. Here's an example:

class GalleryFragment extends Fragment {
    private Gallery gallery;

    (...)

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        gallery = (Gallery) view.findViewById(R.id.gallery);
        gallery.setAdapter(adapter);
        super.onViewCreated(view, savedInstanceState);
    }
}

The method wont work on fragments outside OnCreate and similar methods.不适用于 OnCreate 和类似方法之外的片段。

You have two ways, pass the view to the function on the oncreate (what means you can only run your functions when the view is being created) or set the view as a variable:

private View rootView;

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

public void doSomething () {
    ImageView thumbnail = (ImageView) rootView.findViewById(R.id.someId);
}

1) first inflate layout of Fragment then you can use findviewbyId .

View view = inflater.inflate(R.layout.testclassfragment, container, false);
             ImageView imageView = (ImageView) view.findViewById(R.id.my_image);
             return view;

agreed with calling findViewById() on the View.

public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View V = inflater.inflate(R.layout.testclassfragment, container, false);
    ImageView imageView = (ImageView) V.findViewById(R.id.my_image);

    return V;
}
EditText name = (EditText) getView().findViewById(R.id.editText1);
EditText add = (EditText) getView().findViewById(R.id.editText2);  

Note :

From API Level 26, you also don't need to specifically cast the result of findViewById as it uses inference for its return type.

So now you can simply do,

public View onCreateView(LayoutInflater inflater, 
                         ViewGroup container, 
                         Bundle savedInstanceState) {
     View view = inflater.inflate(R.layout.testclassfragment, container, false);
     ImageView imageView =  view.findViewById(R.id.my_image); //without casting the return type
     return view;
}

Use

imagebutton = (ImageButton) getActivity().findViewById(R.id.imagebutton1);

imageview = (ImageView) getActivity().findViewById(R.id.imageview1);

it will work

使用getView()返回片段的视图,然后您可以调用findViewById()来访问片段视图中的任何视图元素。

According to the documentation on API level 11

Reference, in Back Stack http://developer.android.com/reference/android/app/Fragment.html

short code

/**
 * The Fragment's UI is just a simple text view showing its
 * instance number.
 */
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    View v = inflater.inflate(R.layout.hello_world, container, false);
    View tv = v.findViewById(R.id.text);
    ((TextView)tv).setText("Fragment #" + mNum);
    tv.setBackgroundDrawable(getResources().getDrawable(android.R.drawable.gallery_thumb));
    return v;
}

Try this it works for me

public class TestClass extends Fragment {
    private ImageView imageView;

    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.testclassfragment, container, false);
        findViews(view);
        return view;
    }

    private void findViews(View view) {
        imageView = (ImageView) view.findViewById(R.id.my_image);
    }
}

The best way to implement this is as follows:

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

rootView = inflater.inflate(R.layout.testclassfragment, container, false);
        ImageView imageView = (ImageView) rootView.findViewById(R.id.my_image);
        return rootView
}

In this way, the rootView can be used for each control defined in the xml layout and the code is much cleaner in this way.

Hope this helps :)

1) Declare your layout file.

public View onCreateView(LayoutInflater inflater,ViewGroup container, 
                                 Bundle savedInstanceState) {
    return inflate(R.layout.myfragment, container, false);
}

2)Then, get the id of your view

@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    TextView nameView = (TextView) view.findViewById(R.id.textview1);
}

Use gradle skeleton plugin , it will automatically generate the view holder classes with the reference to your layout.

public class TestClass extends Fragment {
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        MyLayout myLayout = new MyLayout(inflater, container, false);
        myLayout.myImage.setImageResource(R.drawable.myImage);
        return myLayout.view;
    }
}

Now assuming you had an ImageView declared in your my_layout.xml file, it will automatically generate myLayout class for you.

Try This:

View v = inflater.inflate(R.layout.testclassfragment, container, false);
ImageView img = (ImageView) v.findViewById(R.id.my_image);

return v;

try

private View myFragmentView;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) 
{
myFragmentView = inflater.inflate(R.layout.myLayoutId, container, false);
myView = myFragmentView.findViewById(R.id.myIdTag)
return myFragmentView;
}

You can call findViewById() with the Activity Object you get inside your public void onAttach(Activity activity) method inside your Fragment.

Save the Activity into a variable for example:

In the Fragment class : private Activity mainActivity; In the onAttach() method: this.mainActivity=activity;

Finally execute every findViewById through the vairable: mainActivity.findViewById(R.id.TextView);

There is one more method called onViewCreated.

@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    ImageView imageView = (ImageView) view.findViewById(R.id.imageview1);
}

I like everything to be structured. You can do in this way.

First initialize view

private ImageView imageView;

Then override OnViewCreated

@Override
    public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        findViews(view);
    }

Then add a void method to find views

private void findViews(View v) {
    imageView = v.findViewById(R.id.img);
}

Inside onCreateView method

1) first you have to inflate the layout/view you want to add eg. LinearLayout

LinearLayout ll = inflater.inflate(R.layout.testclassfragment, container, false);

2) Then you can find your imageView id from layout

ImageView imageView = (ImageView)ll.findViewById(R.id.my_image);

3)return the inflated layout

return ll;

You have to inflate the view

public class TestClass extends Fragment {

public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View v = inflater.inflate(R.layout.testclassfragment, container, false);
    ImageView imageView = (ImageView)v.findViewById(R.id.my_image);
    return v
}}

In fragments we need a view of that window so that we make a onCreateView of this Fragment.

Then get the view and use it to access each and every view id of that view elements..

  class Demo extends Fragment
    {
        @Override
        public View onCreateView(final LayoutInflater inflater,ViewGroup container, Bundle savedInstanceState)
        {
            View view =inflater.inflate(R.layout.demo_fragment, container,false);
            ImageView imageview=(ImageView)view.findViewById(R.id.imageview1);

            return view;
        }
    }

Layout inflater comes into picture here. Layout inflater is a class that make us able to use the XML views in java code. So you can inflate the root xml view in variable v with the following code. And then using v, you can find the child views of the root view v.

public class TestClass extends Fragment {
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View v = inflater.inflate(R.layout.testclassfragment, container, false);
    ImageView imageView = (ImageView)v.findViewById(R.id.my_image);
    return v;
    }
}

I am trying to create an ImageView in a Fragment which will refer to the ImageView element which I have created in the XML for the Fragment. However, the findViewById method only works if I extend an Activity class. Is there anyway of which I can use it in Fragment as well?

public class TestClass extends Fragment {
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        ImageView imageView = (ImageView)findViewById(R.id.my_image);
        return inflater.inflate(R.layout.testclassfragment, container, false);
    }
}

The findViewById method has an error on it which states that the method is undefined.

//here you can do it by
   public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState)
  {
    // Inflate the layout for this fragment
    final View view =  inflater.inflate(R.layout.fragment_apple, container, 
 false);
    ist = view.findViewById(R.id.linearLink);
    second = view.findViewById(R.id.linearPhone);
    return view;

The easiest way to use such things is to use butterknife By this you can add as many Onclciklisteners just by @OnClick() as described below:

public class TestClass extends Fragment {
    @BindView(R.id.my_image) ImageView imageView;
    @OnClick(R.id.my_image)
    public void my_image_click(){
        yourMethod();
    }
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view=inflater.inflate(R.layout.testclassfragment, container, false);
        ButterKnife.bind(getActivity,view);
        return view;
    }
}

Very simple way to do:

 @Nullable
        @Override
        public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
            View fragmentView = inflater.inflate(R.layout.testclassfragment, container, false);
            ImageView imageView = (ImageView)fragmentView.findViewById(R.id.my_image);
            return fragmentView;
       }
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
     View view = inflater.inflate(R.layout.testclassfragment, container, false);
     ImageView imageView = (ImageView) view.findViewById(R.id.my_image);
     return view;
}

Notice if you use getView() method it might cause nullPointerException because it returns the rootview and it will be some view after onCreateView() method.

private val recyclerView: RecyclerView by lazy { requireView().findViewById() }
ImageView imageView;
public View onCreateView(LayoutInflater inflater, 
                     ViewGroup container, 
                     Bundle savedInstanceState) {
 View view = inflater.inflate(R.layout.testclassfragment, container, false);
 imageView = view.findViewById(R.id.my_image);
 return view;

}

Timing of transaction after .commit() may also cause this issue

I got the same issue (View in a Fragment could not be reached). The reason turned out to be, that - immediately after (FragmentTransaction) .commit() -, the View had not been activated in the UI. There is no guarantee when , after .commit(), the transaction takes place; it's only queued. So I added a (FragmentManager) .executePendingTransactions() to force the transaction to be done. After that, referencing the View works as expected !

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