Added in API level 1

ExpandableListAdapter

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Kotlin |Java

interface ExpandableListAdapter

android.widget.ExpandableListAdapter

Known Direct Subclasses BaseExpandableListAdapter BaseExpandableListAdapter Base class for a ExpandableListAdapter used to provide data and Views from some data to an expandable list view.

Known Indirect Subclasses CursorTreeAdapter, ResourceCursorTreeAdapter, SimpleCursorTreeAdapter, SimpleExpandableListAdapter CursorTreeAdapter An adapter that exposes data from a series of Cursors to an ExpandableListView widget. ResourceCursorTreeAdapter A fairly simple ExpandableListAdapter that creates views defined in an XML file. SimpleCursorTreeAdapter An easy adapter to map columns from a cursor to TextViews or ImageViews defined in an XML file. SimpleExpandableListAdapter An easy adapter to map static data to group and child views defined in an XML file.

An adapter that links a ExpandableListView with the underlying data. The implementation of this interface will provide access to the data of the children (categorized by groups), and also instantiate Views for children and groups.

Summary

Public methods
abstract Boolean	areAllItemsEnabled()
abstract Any!	getChild(groupPosition: Int, childPosition: Int) Gets the data associated with the given child within the given group.
abstract Long	getChildId(groupPosition: Int, childPosition: Int) Gets the ID for the given child within the given group.
abstract View!	getChildView(groupPosition: Int, childPosition: Int, isLastChild: Boolean, convertView: View!, parent: ViewGroup!) Gets a View that displays the data for the given child within the given group.
abstract Int	getChildrenCount(groupPosition: Int) Gets the number of children in a specified group.
abstract Long	getCombinedChildId(groupId: Long, childId: Long) Gets an ID for a child that is unique across any item (either group or child) that is in this list.
abstract Long	getCombinedGroupId(groupId: Long) Gets an ID for a group that is unique across any item (either group or child) that is in this list.
abstract Any!	getGroup(groupPosition: Int) Gets the data associated with the given group.
abstract Int	getGroupCount() Gets the number of groups.
abstract Long	getGroupId(groupPosition: Int) Gets the ID for the group at the given position.
abstract View!	getGroupView(groupPosition: Int, isExpanded: Boolean, convertView: View!, parent: ViewGroup!) Gets a View that displays the given group.
abstract Boolean	hasStableIds() Indicates whether the child and group IDs are stable across changes to the underlying data.
abstract Boolean	isChildSelectable(groupPosition: Int, childPosition: Int) Whether the child at the specified position is selectable.
abstract Boolean	isEmpty()
abstract Unit	onGroupCollapsed(groupPosition: Int) Called when a group is collapsed.
abstract Unit	onGroupExpanded(groupPosition: Int) Called when a group is expanded.
abstract Unit	registerDataSetObserver(observer: DataSetObserver!)
abstract Unit	unregisterDataSetObserver(observer: DataSetObserver!)

Public methods

areAllItemsEnabled

Added in API level 1

abstract fun areAllItemsEnabled(): Boolean

See Also

• android.widget.ListAdapter#areAllItemsEnabled()

getChild

Added in API level 1

abstract fun getChild(
    groupPosition: Int, 
    childPosition: Int
): Any!

Gets the data associated with the given child within the given group.

Parameters
groupPosition	Int: the position of the group that the child resides in
childPosition	Int: the position of the child with respect to other children in the group

Return
Any!	the data of the child

getChildId

Added in API level 1

abstract fun getChildId(
    groupPosition: Int, 
    childPosition: Int
): Long

Gets the ID for the given child within the given group. This ID must be unique across all children within the group. The combined ID (see getCombinedChildId(long,long)) must be unique across ALL items (groups and all children).

Parameters
groupPosition	Int: the position of the group that contains the child
childPosition	Int: the position of the child within the group for which the ID is wanted

Return
Long	the ID associated with the child

getChildView

Added in API level 1

abstract fun getChildView(
    groupPosition: Int, 
    childPosition: Int, 
    isLastChild: Boolean, 
    convertView: View!, 
    parent: ViewGroup!
): View!

Gets a View that displays the data for the given child within the given group.

Parameters
groupPosition	Int: the position of the group that contains the child
childPosition	Int: the position of the child (for which the View is returned) within the group
isLastChild	Boolean: Whether the child is the last child within the group
convertView	View!: the old view to reuse, if possible. You should check that this view is non-null and of an appropriate type before using. If it is not possible to convert this view to display the correct data, this method can create a new view. It is not guaranteed that the convertView will have been previously created by getChildView(int,int,boolean,android.view.View,android.view.ViewGroup).
parent	ViewGroup!: the parent that this view will eventually be attached to

Return
View!	the View corresponding to the child at the specified position

getChildrenCount

Added in API level 1

abstract fun getChildrenCount(groupPosition: Int): Int

Gets the number of children in a specified group.

Parameters
groupPosition	Int: the position of the group for which the children count should be returned

Return
Int	the children count in the specified group

getCombinedChildId

Added in API level 1

abstract fun getCombinedChildId(
    groupId: Long, 
    childId: Long
): Long

Gets an ID for a child that is unique across any item (either group or child) that is in this list. Expandable lists require each item (group or child) to have a unique ID among all children and groups in the list. This method is responsible for returning that unique ID given a child's ID and its group's ID. Furthermore, if hasStableIds() is true, the returned ID must be stable as well.

Parameters
groupId	Long: The ID of the group that contains this child.
childId	Long: The ID of the child.

Return
Long	The unique (and possibly stable) ID of the child across all groups and children in this list.

getCombinedGroupId

Added in API level 1

abstract fun getCombinedGroupId(groupId: Long): Long

Gets an ID for a group that is unique across any item (either group or child) that is in this list. Expandable lists require each item (group or child) to have a unique ID among all children and groups in the list. This method is responsible for returning that unique ID given a group's ID. Furthermore, if hasStableIds() is true, the returned ID must be stable as well.

Parameters
groupId	Long: The ID of the group

Return
Long	The unique (and possibly stable) ID of the group across all groups and children in this list.

getGroup

Added in API level 1

abstract fun getGroup(groupPosition: Int): Any!

Gets the data associated with the given group.

Parameters
groupPosition	Int: the position of the group

Return
Any!	the data child for the specified group

getGroupCount

Added in API level 1

abstract fun getGroupCount(): Int

Gets the number of groups.

Return
Int	the number of groups

getGroupId

Added in API level 1

abstract fun getGroupId(groupPosition: Int): Long

Gets the ID for the group at the given position. This group ID must be unique across groups. The combined ID (see getCombinedGroupId(long)) must be unique across ALL items (groups and all children).

Parameters
groupPosition	Int: the position of the group for which the ID is wanted

Return
Long	the ID associated with the group

getGroupView

Added in API level 1

abstract fun getGroupView(
    groupPosition: Int, 
    isExpanded: Boolean, 
    convertView: View!, 
    parent: ViewGroup!
): View!

Gets a View that displays the given group. This View is only for the group--the Views for the group's children will be fetched using getChildView(int,int,boolean,android.view.View,android.view.ViewGroup).

Parameters
groupPosition	Int: the position of the group for which the View is returned
isExpanded	Boolean: whether the group is expanded or collapsed
convertView	View!: the old view to reuse, if possible. You should check that this view is non-null and of an appropriate type before using. If it is not possible to convert this view to display the correct data, this method can create a new view. It is not guaranteed that the convertView will have been previously created by getGroupView(int,boolean,android.view.View,android.view.ViewGroup).
parent	ViewGroup!: the parent that this view will eventually be attached to

Return
View!	the View corresponding to the group at the specified position

hasStableIds

Added in API level 1

abstract fun hasStableIds(): Boolean

Indicates whether the child and group IDs are stable across changes to the underlying data.

Return
Boolean	whether or not the same ID always refers to the same object

See Also

• android.widget.Adapter#hasStableIds()

isChildSelectable

Added in API level 1

abstract fun isChildSelectable(
    groupPosition: Int, 
    childPosition: Int
): Boolean

Whether the child at the specified position is selectable.

Parameters
groupPosition	Int: the position of the group that contains the child
childPosition	Int: the position of the child within the group

Return
Boolean	whether the child is selectable.

isEmpty

Added in API level 1

abstract fun isEmpty(): Boolean

See Also

• android.widget.ListAdapter#isEmpty()

onGroupCollapsed

Added in API level 1

abstract fun onGroupCollapsed(groupPosition: Int): Unit

Called when a group is collapsed.

Parameters
groupPosition	Int: The group being collapsed.

onGroupExpanded

Added in API level 1

abstract fun onGroupExpanded(groupPosition: Int): Unit

Called when a group is expanded.

Parameters
groupPosition	Int: The group being expanded.

registerDataSetObserver

Added in API level 1

abstract fun registerDataSetObserver(observer: DataSetObserver!): Unit

See Also

• android.widget.Adapter#registerDataSetObserver(DataSetObserver)

unregisterDataSetObserver

Added in API level 1

abstract fun unregisterDataSetObserver(observer: DataSetObserver!): Unit

See Also

• android.widget.Adapter#unregisterDataSetObserver(DataSetObserver)