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View.getRoot() returns View, so we can easily figure out which is the root view by using getResourceName(View.getId()).
View.getParent()..., while I expect it also returns View that is the parent, actually only returns an instance of ViewParent that seems to have very very few useful method/fields. It sucks.
So, is there any way to know the ID of the parent? I believe a View's parent is also View, thus it should has mID field.
I really wonder why Google didn't let View.getParent() just returns View. It makes sense, only when something else other than View could be the parent, and as far as I know, it's limited to View and its subclasses.
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A ViewGroup "is a special view that can contain other views (called children.)" It's the superclass for all of the Layout classes. Parent view refers to a specific parent-child relationship (This RelativeLayout is the parent of this ImageView).
In android (and most other technologies), views can have subviews, aka "children". Most views can have children and can be a child of a parent view. It's kind of like a "tree". The most obvious feature of being a child of some other view is that the child moves with the parent view.
Defines the responsibilities for a class that will be a parent of a View. This is the API that a view sees when it wants to interact with its parent.
Step 1 − Create a new project in Android Studio,go to File ⇒ New Project and fill all required details to create a new project. Step 2 − Add the following code to res/layout/activity_main.xml. In the above example we don't have any view, we have created a root view /parent view. we can add child view in java as shown below −
However, if you have already defined an ID resource (and it is not already used), then you can apply that ID to a View element by excluding the plus symbol in the android:id value. The height and width value can be expressed using any of the dimension units supported by Android (px, dp, sp, pt, in, mm) or with the following keywords:
The getParent method returns a ViewParent, not a View. You need to cast the first call to getParent() also: RelativeLayout r = (RelativeLayout) ((ViewGroup) this.getParent()).getParent(); As stated in the comments by the OP, this is causing a NPE.
To find a view programmatically, the View (LinearLayout / TextView / Button / ImageView / EditText etc.) should have been set with an id in the layout xml file as shown below : Button View with id, in layout xml file. <Button. android:id="@+id/button_submit".
ViewParent is just an interface that any View that can have children implements. Most of the times the class you get back will be an instance of a ViewGroup, like LinearLayout or RelativeLayout. I'm not exactly sure what you mean by "name" but if you want to get the class name you can do so like always: view.getParent().getClass().getName().
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The docs state that the parent is not necessarily a View:
public final ViewParent getParent ()
Added in API level 1 Gets the parent of this view. Note that the parent is a ViewParent and not necessarily a View.
Returns Parent of this view.
However all implementations of ViewParent inherit from View. This should be a design decision to decouple the parent from a View using the ViewParent interface, although all implementations in the SDK are views.
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Try casting it first. For example, if the parent of the View that you're trying to get id of is a TableRow, then do
((TableRow)View.getParent()).getID()
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