What is showAsAction android?
android:showAsAction Keyword. When and how this item should appear as an action item in the app bar. A menu item can appear as an action item only when the activity includes an app bar.
How the android showAsAction attribute is used with android item menu?
android:showAsAction. Specifies when and how this item should appear as an action item in the app bar. These are the most important attributes you should use, but there are many more available. For information about all the supported attributes, see the Menu Resource document.
What is order in category in android?
android:orderInCategory is an integer attribute that dictates the order in which the menu items will appear within the menu when it is displayed.
What are the menus in android?
There are three types of menus in Android: Popup, Contextual and Options. Each one has a specific use case and code that goes along with it. To learn how to use them, read on. Each menu must have an XML file related to it which defines its layout.
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 are two types of popup menu?
Usage
- Contextual Action Modes – An “action mode” which is enabled when a user selects an item. …
- PopupMenu – A modal menu that is anchored to a particular view within an activity. …
- PopupWindow – A simple dialog box that gains focus when appearing on screen.
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 onCreateOptionsMenu in android?
You use onCreateOptionsMenu() to specify the options menu for an activity. In this method, you can inflate your menu resource (defined in XML) into the Menu provided in the callback.
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.
What is intent class in Android?
An Intent is a messaging object which provides a facility for performing late runtime binding between the code in different applications in the Android development environment.
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 the main component in Android?
Android applications are broken down into four main components: activities, services, content providers, and broadcast receivers. Approaching Android from these four components gives the developer the competitive edge to be a trendsetter in mobile application development.
What is use of SharedPreferences in android?
A SharedPreferences object points to a file containing key-value pairs and provides simple methods to read and write them. Each SharedPreferences file is managed by the framework and can be private or shared. This page shows you how to use the SharedPreferences APIs to store and retrieve simple values.