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Android - An Open Handset Alliance Project

android.widget
public interface

android.widget.ExpandableListAdapter

android.widget.ExpandableListAdapter

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.

Known Indirect Subclasses

Summary

Public Methods

        boolean  areAllItemsSelectable()
Are all items in this ExpandableListAdapter selectable?
        Object  getChild(int groupPosition, int childPosition)
Gets the data associated with the given child within the given group.
        long  getChildId(int groupPosition, int childPosition)
Gets the ID for the given child within the given group.
        View  getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent)
Gets a View that displays the data for the given child within the given group.
        int  getChildrenCount(int groupPosition)
Gets the number of children in a specified group.
        long  getCombinedChildId(long groupId, long childId)
Gets an ID for a child that is unique across any item (either group or child) that is in this list.
        long  getCombinedGroupId(long groupId)
Gets an ID for a group that is unique across any item (either group or child) that is in this list.
        Object  getGroup(int groupPosition)
Gets the data associated with the given group.
        int  getGroupCount()
Gets the number of groups.
        long  getGroupId(int groupPosition)
Gets the ID for the group at the given position.
        View  getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent)
Gets a View that displays the given group.
        long  getNewSelectionForKey(long packedPosition, int keyCode, KeyEvent event)
Given a keyboard key, let the adapter suggest the group/child to be made the new selected child.
        boolean  isChildSelectable(int groupPosition, int childPosition)
Whether the child at the specified position is selectable.
        void  onGroupCollapsed(int groupPosition)
Called when a group is being collapsed.
        void  onGroupExpanded(int groupPosition)
Called when a group is being expanded.
        void  registerDataSetObserver(DataSetObserver observer)
Register an observer that is called when changes happen to the data used by this adapter.
        boolean  stableIds()
Indicates whether the child and group IDs are stable across changes to the underlying data.
        void  unregisterDataSetObserver(DataSetObserver observer)
Unregister an observer that has previously been registered with this adapter via registerDataSetObserver(DataSetObserver).

Details

Public Methods

public boolean areAllItemsSelectable()

Are all items in this ExpandableListAdapter selectable?

Returns

  • True if all items are selectable.

public Object getChild(int groupPosition, int childPosition)

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

Parameters

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

Returns

  • the data of the child

public long getChildId(int groupPosition, int childPosition)

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 the position of the group that contains the child
childPosition the position of the child within the group for which the ID is wanted

Returns

  • the ID associated with the child

public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent)

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

Parameters

groupPosition the position of the group that contains the child
childPosition the position of the child (for which the View is returned) within the group
isLastChild Whether the child is the last child within the group
convertView 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, View, ViewGroup).
parent the parent that this view will eventually be attached to

Returns

  • the View corresponding to the child at the specified position

public int getChildrenCount(int groupPosition)

Gets the number of children in a specified group.

Parameters

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

Returns

  • the children count in the specified group

public long getCombinedChildId(long groupId, long childId)

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 stableIds() is true, the returned ID must be stable as well.

Parameters

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

Returns

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

public long getCombinedGroupId(long groupId)

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 stableIds() is true, the returned ID must be stable as well.

Parameters

groupId The ID of the group

Returns

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

public Object getGroup(int groupPosition)

Gets the data associated with the given group.

Parameters

groupPosition the position of the group

Returns

  • the data child for the specified group

public int getGroupCount()

Gets the number of groups.

Returns

  • the number of groups

public long getGroupId(int groupPosition)

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 the position of the group for which the ID is wanted

Returns

  • the ID associated with the group

public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent)

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 getChildrenView.

Parameters

groupPosition the position of the group for which the View is returned
isExpanded whether the group is expanded or collapsed
convertView 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, View, ViewGroup).
parent the parent that this view will eventually be attached to

Returns

  • the View corresponding to the group at the specified position

public long getNewSelectionForKey(long packedPosition, int keyCode, KeyEvent event)

Given a keyboard key, let the adapter suggest the group/child to be made the new selected child. Return PACKED_POSITION_VALUE_NULL to indicate no appropriate key (for example, the user pressed the back button, or a subclass does not support this feature) or for no preference.

Parameters

packedPosition the packed position of the currently selected child
keyCode the keyCode for the event
event the full key event structure

Returns

  • the new selection's position

See Also

public boolean isChildSelectable(int groupPosition, int childPosition)

Whether the child at the specified position is selectable.

Parameters

groupPosition the position of the group that contains the child
childPosition the position of the child within the group

Returns

  • whether the child is selectable.

public void onGroupCollapsed(int groupPosition)

Called when a group is being collapsed.

Parameters

groupPosition The group being collapsed.

public void onGroupExpanded(int groupPosition)

Called when a group is being expanded.

Parameters

groupPosition The group being expanded.

public void registerDataSetObserver(DataSetObserver observer)

Register an observer that is called when changes happen to the data used by this adapter.

Parameters

observer the object that gets notified when the data set changes.

public boolean stableIds()

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

Returns

  • whether or not the same ID always refers to the same object

public void unregisterDataSetObserver(DataSetObserver observer)

Unregister an observer that has previously been registered with this adapter via registerDataSetObserver(DataSetObserver).

Parameters

observer the object to unregister.
Build m5-rc15g - 14 May 2008 12:50