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attachToRoot: attaches the views to their parent (includes them in the parent hierarchy), so any touch event that the views recieve will also be transfered to parent view.
What is use of LayoutInflater in Android?
The LayoutInflater class is used to instantiate the contents of layout XML files into their corresponding View objects. In other words, it takes an XML file as input and builds the View objects from it.
What is root in inflate?
The first parameter points to the layout resource you want to inflate. The second parameter is the root view of the hierarchy you are inflating the resource to attach to. When the third parameter is present, it governs whether or not the inflated view is attached to the supplied root after inflation.
What does it mean to inflate a layout?
Solution: When you write an XML layout, it will be inflated by the Android OS which basically means that it will be rendered by creating view object in memory.
What is inflation Android?
What is an Inflater ? To summarize what the LayoutInflater Documentation says A LayoutInflater is one of the Android System Services that is responsible for taking your XML files that define a layout, and converting them into View objects. The OS then uses these view objects to draw the screen.
What is onCreateOptionsMenu in android?
In this method, you can inflate your menu resource (defined in XML) into the Menu provided in the callback. For example: @Override public boolean onCreateOptionsMenu(Menu menu) { MenuInflater inflater = getMenuInflater(); inflater.inflate(R.menu.game_menu, menu); return true; }Jan 7, 2018.
What is an ArrayAdapter in android?
ArrayAdapter is the most commonly used adapter in android. When you have a list of single type items which are stored in an array you can use ArrayAdapter. Likewise, if you have a list of phone numbers, names, or cities. ArrayAdapter has a layout with a single TextView.
What is SetContentView?
SetContentView is used to fill the window with the UI provided from layout file incase of setContentView(R. layout. somae_file). Here layoutfile is inflated to view and added to the Activity context(Window).
What does Inflater mean?
transitive verb. 1 : to swell or distend with air or gas. 2 : to puff up : elate inflate one’s ego. 3 : to expand or increase abnormally or imprudently.
What are views in android?
View is a basic building block of UI (User Interface) in android. A view is a small rectangular box that responds to user inputs. Eg: EditText, Button, CheckBox, etc. ViewGroup is an invisible container of other views (child views) and other ViewGroup. Eg: LinearLayout is a ViewGroup that can contain other views in it.
What is content view in Android Studio?
public abstract @interface ContentView. implements Annotation. androidx.annotation.ContentView. Annotation that can be attached to a constructor with a single LayoutRes parameter to denote what layout the component intends to inflate and set as its content.
How are attributes read and drawn and how many passes does a view before it’s completely shown on screen?
In turn, each ViewGroup is responsible for requesting each of its children to be drawn (with the draw() method) and each View is responsible for drawing itself. Drawing the layout is a two pass process: a measure pass and a layout pass.
What is onClick android?
When the user clicks a button, the Button object receives an on-click event. To define the click event handler for a button, add the android:onClick attribute to the <Button> element in your XML layout. The value for this attribute must be the name of the method you want to call in response to a click event.
What is android ViewGroup?
A ViewGroup is a special view that can contain other views. The ViewGroup is the base class for Layouts in android, like LinearLayout , RelativeLayout , FrameLayout etc. In other words, ViewGroup is generally used to define the layout in which views(widgets) will be set/arranged/listed on the android screen.
How do I make my android invisible?
setVisibility(View. GONE); you have the option to set the visibility to INVISIBLE and VISIBLE . Then you can play with the visibility as you like.
Which is valid menu in android?
<menu> Defines a Menu , which is a container for menu items. A <menu> element must be the root node for the file and can hold one or more <item> and <group> elements. <item>Nov 22, 2020.
What is the use of Menuinflater in android?
This class is used to instantiate menu XML files into Menu objects. For performance reasons, menu inflation relies heavily on pre-processing of XML files that is done at build time.
What is invalidateOptionsMenu in android?
invalidateOptionsMenu() is used to say Android, that contents of menu have changed, and menu should be redrawn. For example, you click a button which adds another menu item at runtime, or hides menu items group. In this case you should call invalidateOptionsMenu() , so that the system could redraw it on UI.
What is an AdapterView in Android?
An AdapterView is a group of widgets (aka view) components in Android that include the ListView, Spinner, and GridView. In general, these are the widgets that provide the selecting capability in the user interface (read about AdapterView widgets here).
What are activities in android?
You implement an activity as a subclass of the Activity class. An activity provides the window in which the app draws its UI. Generally, one activity implements one screen in an app. For instance, one of an app’s activities may implement a Preferences screen, while another activity implements a Select Photo screen.
What is a layout in Android?
Layouts Part of Android Jetpack. A layout defines the structure for a user interface in your app, such as in an activity. All elements in the layout are built using a hierarchy of View and ViewGroup objects. A View usually draws something the user can see and interact with.