Get root view from current activity

685
votes

I know how to get the root view with View.getRootView(). I am also able to get the view from a button's onClick event where the argument is a View. But how can I get the view in an activity?

12
androidandroid-activityview
In activity, normally you tell which resource it should render using setContentView() and the view that you supplied is already the root. If you need the handle of that view, simply put an ID to it in XAML and findViewById() would be fine. – xandy
My plan is to attach the code dynamically .. so if my users use the api I expect it to be automatically detect things.. Boulder's solution works ! – Lalith
@xandy: a slight typo: XAML -> XML. – superjos

12 Answers

1117
votes

If you need root view of your activity (so you can add your contents there) use

findViewById(android.R.id.content).getRootView()

Also it was reported that on some devices you have to use 

getWindow().getDecorView().findViewById(android.R.id.content)

instead.

Please note that as Booger reported, this may be behind navigation bar (with back button etc.) on some devices (but it seems on most devices it is not).

If you need to get view that you added to your activity using setContentView() method then as pottedmeat wrote you can use

final ViewGroup viewGroup = (ViewGroup) ((ViewGroup) this
            .findViewById(android.R.id.content)).getChildAt(0);

But better just set id to this view in your xml layout and use this id instead.

274
votes

This is what I use to get the root view as found in the XML file assigned with setContentView:

final ViewGroup viewGroup = (ViewGroup) ((ViewGroup) this
            .findViewById(android.R.id.content)).getChildAt(0);
145
votes

I tested this in android 4.0.3, only:

getWindow().getDecorView().getRootView()

give the same view what we get from 

anyview.getRootView();

com.android.internal.policy.impl.PhoneWindow$DecorView@#########

and 

getWindow().getDecorView().findViewById(android.R.id.content)

giving child of its

android.widget.FrameLayout@#######

Please confirm.

34
votes

Get root view from current activity.

Inside our activity we can get the root view with:

ViewGroup rootView = (ViewGroup) ((ViewGroup) this
            .findViewById(android.R.id.content)).getChildAt(0);

or

View rootView = getWindow().getDecorView().getRootView();
28
votes

In Kotlin we can do it a little shorter:

val rootView = window.decorView.rootView
20
votes

Just incase Someone needs an easier way:

The following code gives a view of the whole activity:

View v1 = getWindow().getDecorView().getRootView();

To get a certian view in the activity,for example an imageView inside the activity, simply add the id of that view you want to get:

View v1 = getWindow().getDecorView().getRootView().findViewById(R.id.imageView1);

Hope this helps somebody

7
votes

Kotlin Extension Solution

Use this to simplify access in an Activity. Then you can directly refer to rootView from the Activity, or activity.rootView outside of it:

val Activity.rootView get() = window.decorView.rootView

If you'd like to add the same for Fragments for consistency, add:

val Fragment.rootView get() = view?.rootView
4
votes

anyview.getRootView(); will be the easiest way.

4
votes

For those of you who are using the Data Binding Library, to get the root of the current activity, simply use:

View rootView = dataBinding.getRoot();

And for Kotlin users, it's even simpler:

val rootView = dataBinding.root
2
votes

Another Kotlin Extension solution

If your activity's view is declared in xml (ex activity_root.xml), open the xml and assign an id to the root view:

android:id="@+id/root_activity"

Now in your class, import the view using:

import kotlinx.android.synthetic.main.activity_root.root_activity

You can now use root_activity as the view.

1
votes

to get View of the current Activity

in any onClick we will be getting "View view", by using 'view' get the rootView.

View view = view.getRootView();

and to get View in fragment

View view = FragmentClass.getView();

0
votes

if you are in a activity, assume there is only one root view,you can get it like this.

ViewGroup viewGroup = (ViewGroup) ((ViewGroup) this
        .findViewById(android.R.id.content)).getChildAt(0);

you can then cast it to your real class

or you could using 

getWindow().getDecorView();

notice this will include the actionbar view, your view is below the actionbar view