What is xmlns tools in Android?
Namespaces are a way for XML documents to include tags from various vendors. By using xmlns attribute you declare, that, by default, you’re using XML elements defined here: http://schemas.android.com/apk/res/android (note that this link is broken – this discussion explains why).
What is the use of tools context?
tools:context is such an attribute that is defined in any root view and declares which activity or fragment the layout is associated with. This declaration helps in enabling various features in the layout preview which demands the knowledge of the activity such as automatically choosing the necessary theme for preview.
What is Tools targetApi?
tools:targetApi This tells the tools that you believe this element (and any children) will be used only on the specified API level or higher. This stops lint from warning you if that element or its attributes are not available on the API level you specify as your minSdkVersion .
What does xmlns mean in XML?
the xml namespace
The xmlns attribute specifies the xml namespace for a document. Note: The xmlns attribute is required in XHTML, invalid in HTML 4.01, and optional in HTML5. Note: The HTML validator at http://w3.org does not complain when the xmlns attribute is missing in an XHTML document.
What tool do we use to display images in android?
Android provides views which can be used to display images from various sources and provide transitions between them. Some of these views are the ImageView and the ImageSwitcher .
What is context layout?
“tools:context” is one of the Design Attributes that can facilitate layout creation in XML in the development framework. This attribute is used to show the development framework what activity class is picked for implementing the layout.
What is target API M?
By adding tools:targetApi=”m” to an element you tell the lint that the element won’t be used on API level below 23 (M). See the attribute documentation. This tells the tools that you believe this element (and any children) will be used only on the specified API level or higher.
What is TargetApi?
public abstract @interface TargetApi. implements Annotation. android.annotation.TargetApi. Indicates that Lint should treat this type as targeting a given API level, no matter what the project target is.
What is difference between View and ViewGroup?
View is a simple rectangle box that responds to the user’s actions. ViewGroup is a collection of Views(TextView, EditText, ListView, etc..), somewhat like a container. A View object is a component of the user interface (UI) like a button or a text box, and it’s also called a widget.
What is ViewGroup container?
Eg: EditText , Button , CheckBox , etc.. ViewGroup is a invisible container of other views (child views) and other viewgroups. Eg: LinearLayout is a viewgroup which can contain other views in it.
How does xmlns work?
An XML namespace is a collection of names that can be used as element or attribute names in an XML document. The namespace qualifies element names uniquely on the Web in order to avoid conflicts between elements with the same name.
What is the purpose of xmlns attribute?
The xmlns attribute specifies the xml namespace for a document. Note: The xmlns attribute is required in XHTML, invalid in HTML 4.01, and optional in HTML5. Note: The HTML validator at http://w3.org does not complain when the xmlns attribute is missing in an XHTML document.
What is Google volley?
Volley is an HTTP library that makes networking for Android apps easier and most importantly, faster. Volley is available on GitHub. Volley offers the following benefits: Automatic scheduling of network requests. Multiple concurrent network connections.
Why is RecyclerView used?
RecyclerView makes it easy to efficiently display large sets of data. You supply the data and define how each item looks, and the RecyclerView library dynamically creates the elements when they’re needed. As the name implies, RecyclerView recycles those individual elements.
What is CSS context?
A block formatting context (BFC) is a part of a visual CSS rendering of a web page. It’s the region in which the layout of block boxes occurs and in which floats interact with other elements. A block formatting context is created by at least one of the following: The root element of the document ( ).