LayoutInflater
abstract class LayoutInflater
kotlin.Any | |
↳ | android.view.LayoutInflater |
Instantiates a layout XML file into its corresponding android.view.View
objects. It is never used directly. Instead, use android.app.Activity#getLayoutInflater()
or android.content.Context#getSystemService to retrieve a standard LayoutInflater instance that is already hooked up to the current context and correctly configured for the device you are running on.
To create a new LayoutInflater with an additional Factory
for your own views, you can use cloneInContext
to clone an existing ViewFactory, and then call setFactory
on it to include your Factory.
For performance reasons, view inflation relies heavily on pre-processing of XML files that is done at build time. Therefore, it is not currently possible to use LayoutInflater with an XmlPullParser over a plain XML file at runtime; it only works with an XmlPullParser returned from a compiled resource (R.something file.)
Note: This class is not thread-safe and a given instance should only be accessed by a single thread.
Summary
Nested classes | |
---|---|
abstract | |
abstract | |
abstract |
Hook to allow clients of the LayoutInflater to restrict the set of Views that are allowed to be inflated. |
Protected constructors | |
---|---|
LayoutInflater(context: Context!) Create a new LayoutInflater instance associated with a particular Context. |
|
LayoutInflater(original: LayoutInflater!, newContext: Context!) Create a new LayoutInflater instance that is a copy of an existing LayoutInflater, optionally with its Context changed. |
Public methods | |
---|---|
abstract LayoutInflater! |
cloneInContext(newContext: Context!) Create a copy of the existing LayoutInflater object, with the copy pointing to a different Context than the original. |
View! |
createView(name: String!, prefix: String!, attrs: AttributeSet!) Low-level function for instantiating a view by name. |
View? |
createView(viewContext: Context, name: String, prefix: String?, attrs: AttributeSet?) Low-level function for instantiating a view by name. |
open static LayoutInflater! |
Obtains the LayoutInflater from the given context. |
open Context! |
Return the context we are running in, for access to resources, class loader, etc. |
LayoutInflater.Factory! |
Return the current |
LayoutInflater.Factory2! |
Return the current |
open LayoutInflater.Filter! | |
open View! |
Inflate a new view hierarchy from the specified xml resource. |
open View! |
inflate(parser: XmlPullParser!, root: ViewGroup?) Inflate a new view hierarchy from the specified xml node. |
open View! |
Inflate a new view hierarchy from the specified xml resource. |
open View! |
inflate(parser: XmlPullParser!, root: ViewGroup?, attachToRoot: Boolean) Inflate a new view hierarchy from the specified XML node. |
open View? |
onCreateView(viewContext: Context, parent: View?, name: String, attrs: AttributeSet?) Version of |
open Unit |
setFactory(factory: LayoutInflater.Factory!) Attach a custom Factory interface for creating views while using this LayoutInflater. |
open Unit |
setFactory2(factory: LayoutInflater.Factory2!) Like |
open Unit |
setFilter(filter: LayoutInflater.Filter!) Sets the |
Protected methods | |
---|---|
open View! |
onCreateView(name: String!, attrs: AttributeSet!) This routine is responsible for creating the correct subclass of View given the xml element name. |
open View! |
onCreateView(parent: View!, name: String!, attrs: AttributeSet!) Version of |
Protected constructors
LayoutInflater
protected LayoutInflater(context: Context!)
Create a new LayoutInflater instance associated with a particular Context. Applications will almost always want to use android.content.Context#getSystemService to retrieve the standard Context.INFLATER_SERVICE
.
Parameters | |
---|---|
context |
Context!: The Context in which this LayoutInflater will create its Views; most importantly, this supplies the theme from which the default values for their attributes are retrieved. |
LayoutInflater
protected LayoutInflater(
original: LayoutInflater!,
newContext: Context!)
Create a new LayoutInflater instance that is a copy of an existing LayoutInflater, optionally with its Context changed. For use in implementing cloneInContext
.
Parameters | |
---|---|
original |
LayoutInflater!: The original LayoutInflater to copy. |
newContext |
Context!: The new Context to use. |
Public methods
cloneInContext
abstract fun cloneInContext(newContext: Context!): LayoutInflater!
Create a copy of the existing LayoutInflater object, with the copy pointing to a different Context than the original. This is used by ContextThemeWrapper
to create a new LayoutInflater to go along with the new Context theme.
Parameters | |
---|---|
newContext |
Context!: The new Context to associate with the new LayoutInflater. May be the same as the original Context if desired. |
Return | |
---|---|
LayoutInflater! |
Returns a brand spanking new LayoutInflater object associated with the given Context. |
createView
fun createView(
name: String!,
prefix: String!,
attrs: AttributeSet!
): View!
Low-level function for instantiating a view by name. This attempts to instantiate a view class of the given name found in this LayoutInflater's ClassLoader. To use an explicit Context in the View constructor, use createView(android.content.Context,java.lang.String,java.lang.String,android.util.AttributeSet)
instead.
There are two things that can happen in an error case: either the exception describing the error will be thrown, or a null will be returned. You must deal with both possibilities -- the former will happen the first time createView() is called for a class of a particular name, the latter every time there-after for that class name.
Parameters | |
---|---|
name |
String!: The full name of the class to be instantiated. |
attrs |
AttributeSet!: The XML attributes supplied for this instance. |
Return | |
---|---|
View! |
View The newly instantiated view, or null. |
createView
fun createView(
viewContext: Context,
name: String,
prefix: String?,
attrs: AttributeSet?
): View?
Low-level function for instantiating a view by name. This attempts to instantiate a view class of the given name found in this LayoutInflater's ClassLoader.
There are two things that can happen in an error case: either the exception describing the error will be thrown, or a null will be returned. You must deal with both possibilities -- the former will happen the first time createView() is called for a class of a particular name, the latter every time there-after for that class name.
Parameters | |
---|---|
viewContext |
Context: The context used as the context parameter of the View constructor This value cannot be null . |
name |
String: The full name of the class to be instantiated. This value cannot be null . |
attrs |
AttributeSet?: The XML attributes supplied for this instance. This value may be null . |
prefix |
String?: This value may be null . |
Return | |
---|---|
View? |
View The newly instantiated view, or null. |
from
open static fun from(context: Context!): LayoutInflater!
Obtains the LayoutInflater from the given context.
getContext
open fun getContext(): Context!
Return the context we are running in, for access to resources, class loader, etc.
getFactory
fun getFactory(): LayoutInflater.Factory!
Return the current Factory
(or null). This is called on each element name. If the factory returns a View, add that to the hierarchy. If it returns null, proceed to call onCreateView(name).
getFactory2
fun getFactory2(): LayoutInflater.Factory2!
Return the current Factory2
. Returns null if no factory is set or the set factory does not implement the Factory2
interface. This is called on each element name. If the factory returns a View, add that to the hierarchy. If it returns null, proceed to call onCreateView(name).
getFilter
open fun getFilter(): LayoutInflater.Filter!
Return | |
---|---|
LayoutInflater.Filter! |
The Filter currently used by this LayoutInflater to restrict the set of Views that are allowed to be inflated. |
inflate
open fun inflate(
resource: Int,
root: ViewGroup?
): View!
Inflate a new view hierarchy from the specified xml resource. Throws InflateException
if there is an error.
Parameters | |
---|---|
resource |
Int: ID for an XML layout resource to load (e.g., R.layout.main_page ) |
root |
ViewGroup?: Optional view to be the parent of the generated hierarchy. This value may be null . |
Return | |
---|---|
View! |
The root View of the inflated hierarchy. If root was supplied, this is the root View; otherwise it is the root of the inflated XML file. |
inflate
open fun inflate(
parser: XmlPullParser!,
root: ViewGroup?
): View!
Inflate a new view hierarchy from the specified xml node. Throws InflateException
if there is an error. *
Important For performance reasons, view inflation relies heavily on pre-processing of XML files that is done at build time. Therefore, it is not currently possible to use LayoutInflater with an XmlPullParser over a plain XML file at runtime.
Parameters | |
---|---|
parser |
XmlPullParser!: XML dom node containing the description of the view hierarchy. |
root |
ViewGroup?: Optional view to be the parent of the generated hierarchy. This value may be null . |
Return | |
---|---|
View! |
The root View of the inflated hierarchy. If root was supplied, this is the root View; otherwise it is the root of the inflated XML file. |
inflate
open fun inflate(
resource: Int,
root: ViewGroup?,
attachToRoot: Boolean
): View!
Inflate a new view hierarchy from the specified xml resource. Throws InflateException
if there is an error.
Parameters | |
---|---|
resource |
Int: ID for an XML layout resource to load (e.g., R.layout.main_page ) |
root |
ViewGroup?: Optional view to be the parent of the generated hierarchy (if attachToRoot is true), or else simply an object that provides a set of LayoutParams values for root of the returned hierarchy (if attachToRoot is false.) This value may be null . |
attachToRoot |
Boolean: Whether the inflated hierarchy should be attached to the root parameter? If false, root is only used to create the correct subclass of LayoutParams for the root view in the XML. |
Return | |
---|---|
View! |
The root View of the inflated hierarchy. If root was supplied and attachToRoot is true, this is root; otherwise it is the root of the inflated XML file. |
inflate
open fun inflate(
parser: XmlPullParser!,
root: ViewGroup?,
attachToRoot: Boolean
): View!
Inflate a new view hierarchy from the specified XML node. Throws InflateException
if there is an error.
Important For performance reasons, view inflation relies heavily on pre-processing of XML files that is done at build time. Therefore, it is not currently possible to use LayoutInflater with an XmlPullParser over a plain XML file at runtime.
Parameters | |
---|---|
parser |
XmlPullParser!: XML dom node containing the description of the view hierarchy. |
root |
ViewGroup?: Optional view to be the parent of the generated hierarchy (if attachToRoot is true), or else simply an object that provides a set of LayoutParams values for root of the returned hierarchy (if attachToRoot is false.) This value may be null . |
attachToRoot |
Boolean: Whether the inflated hierarchy should be attached to the root parameter? If false, root is only used to create the correct subclass of LayoutParams for the root view in the XML. |
Return | |
---|---|
View! |
The root View of the inflated hierarchy. If root was supplied and attachToRoot is true, this is root; otherwise it is the root of the inflated XML file. |
onCreateView
open fun onCreateView(
viewContext: Context,
parent: View?,
name: String,
attrs: AttributeSet?
): View?
Version of onCreateView(android.view.View,java.lang.String,android.util.AttributeSet)
that also takes the inflation context. The default implementation simply calls onCreateView(android.view.View,java.lang.String,android.util.AttributeSet)
.
Parameters | |
---|---|
viewContext |
Context: The Context to be used as a constructor parameter for the View This value cannot be null . |
parent |
View?: The future parent of the returned view. Note that this may be null. |
name |
String: The fully qualified class name of the View to be create. This value cannot be null . |
attrs |
AttributeSet?: An AttributeSet of attributes to apply to the View. This value may be null . |
Return | |
---|---|
View? |
View The View created. This value may be null . |
setFactory
open fun setFactory(factory: LayoutInflater.Factory!): Unit
Attach a custom Factory interface for creating views while using this LayoutInflater. This must not be null, and can only be set once; after setting, you can not change the factory. This is called on each element name as the xml is parsed. If the factory returns a View, that is added to the hierarchy. If it returns null, the next factory default #onCreateView method is called.
If you have an existing LayoutInflater and want to add your own factory to it, use cloneInContext
to clone the existing instance and then you can use this function (once) on the returned new instance. This will merge your own factory with whatever factory the original instance is using.
setFactory2
open fun setFactory2(factory: LayoutInflater.Factory2!): Unit
Like setFactory
, but allows you to set a Factory2
interface.
setFilter
open fun setFilter(filter: LayoutInflater.Filter!): Unit
Sets the Filter
to by this LayoutInflater. If a view is attempted to be inflated which is not allowed by the Filter
, the inflate(int,android.view.ViewGroup)
call will throw an InflateException
. This filter will replace any previous filter set on this LayoutInflater.
Parameters | |
---|---|
filter |
LayoutInflater.Filter!: The Filter which restricts the set of Views that are allowed to be inflated. This filter will replace any previous filter set on this LayoutInflater. |
Protected methods
onCreateView
protected open fun onCreateView(
name: String!,
attrs: AttributeSet!
): View!
This routine is responsible for creating the correct subclass of View given the xml element name. Override it to handle custom view objects. If you override this in your subclass be sure to call through to super.onCreateView(name) for names you do not recognize.
Parameters | |
---|---|
name |
String!: The fully qualified class name of the View to be create. |
attrs |
AttributeSet!: An AttributeSet of attributes to apply to the View. |
Return | |
---|---|
View! |
View The View created. |
onCreateView
protected open fun onCreateView(
parent: View!,
name: String!,
attrs: AttributeSet!
): View!
Version of onCreateView(java.lang.String,android.util.AttributeSet)
that also takes the future parent of the view being constructed. The default implementation simply calls onCreateView(java.lang.String,android.util.AttributeSet)
.
Parameters | |
---|---|
parent |
View!: The future parent of the returned view. Note that this may be null. |
name |
String!: The fully qualified class name of the View to be create. |
attrs |
AttributeSet!: An AttributeSet of attributes to apply to the View. |
Return | |
---|---|
View! |
View The View created. |