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Android - An Open Handset Alliance Project

android.widget
public abstract class

android.widget.CursorTreeAdapter

java.lang.Object
android.widget.BaseExpandableListAdapter ExpandableListAdapter
android.widget.CursorTreeAdapter

An adapter that exposes data from a series of Cursors to an ExpandableListView widget. The top-level Cursor (that is given in the constructor) exposes the groups, while subsequent Cursors returned from getChildrenCursor(Cursor) expose children within a particular group. The Cursors must include a column named "_id" or this class will not work.

Nested Classes
CursorTreeAdapter.MyCursorHelper Helper class for Cursor management:
  • Data validity
  • Funneling the content and data set observers from a Cursor to a single data set observer for widgets
  • ID from the Cursor for use in adapter IDs
  • Swapping cursors but maintaining other metadata  
    		•
    Known Direct Subclasses
    Known Indirect Subclasses

    Summary

    Fields

    protected      MyCursorHelper  mGroupCursorHelper  The cursor helper that is used to get the groups  
    Fields inherited from class android.widget.BaseExpandableListAdapter

    Public Constructors

              CursorTreeAdapter(Cursor cursor, Context context)
    Constructor.
              CursorTreeAdapter(Cursor cursor, Context context, boolean autoRequery)
    Constructor

    Public Methods

            Object  getChild(int groupPosition, int childPosition)
            long  getChildId(int groupPosition, int childPosition)
            View  getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent)
            int  getChildrenCount(int groupPosition)
            Object  getGroup(int groupPosition)
            int  getGroupCount()
            long  getGroupId(int groupPosition)
            View  getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent)
            boolean  isChildSelectable(int groupPosition, int childPosition)
            void  notifyDataSetChanged()
            void  notifyDataSetInvalidated()
            void  onGroupCollapsed(int groupPosition)
    Called when a group is being collapsed.
            boolean  stableIds()

    Protected Methods

    abstract        void  bindChildView(View view, Context context, Cursor cursor, boolean isLastChild)
    Bind an existing view to the child data pointed to by cursor
    abstract        void  bindGroupView(View view, Context context, Cursor cursor, boolean isExpanded)
    Bind an existing view to the group data pointed to by cursor.
      synchronized      void  deactivateChildrenCursorHelper(int groupPosition)
    Deactivates the Cursor and removes the helper from cache.
    abstract        Cursor  getChildrenCursor(Cursor groupCursor)
    Gets the Cursor for the children at the given group.
      synchronized      MyCursorHelper  getChildrenCursorHelper(int groupPosition)
    Gets the cursor helper for the children in the given group.
    abstract        View  newChildView(Context context, Cursor cursor, boolean isLastChild, ViewGroup parent)
    Makes a new child view to hold the data pointed to by cursor.
    abstract        View  newGroupView(Context context, Cursor cursor, boolean isExpanded, ViewGroup parent)
    Makes a new group view to hold the group data pointed to by cursor.
    Methods inherited from class android.widget.BaseExpandableListAdapter
    Methods inherited from class java.lang.Object
    Methods inherited from interface android.widget.ExpandableListAdapter

    Details

    Fields

    protected MyCursorHelper mGroupCursorHelper

    The cursor helper that is used to get the groups

    Public Constructors

    public CursorTreeAdapter(Cursor cursor, Context context)

    Constructor. The adapter will call requery() on the cursor whenever it changes so that the most recent data is always displayed.

    Parameters

    cursor The cursor from which to get the data for the groups.

    public CursorTreeAdapter(Cursor cursor, Context context, boolean autoRequery)

    Constructor

    Parameters

    cursor The cursor from which to get the data for the groups.
    context The context
    autoRequery If true the adapter will call requery() on the cursor whenever it changes so the most recent data is always displayed.

    Public Methods

    public Object getChild(int groupPosition, int childPosition)

    public long getChildId(int groupPosition, int childPosition)

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

    public int getChildrenCount(int groupPosition)

    public Object getGroup(int groupPosition)

    public int getGroupCount()

    public long getGroupId(int groupPosition)

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

    public boolean isChildSelectable(int groupPosition, int childPosition)

    public void notifyDataSetChanged()

    public void notifyDataSetInvalidated()

    public void onGroupCollapsed(int groupPosition)

    Called when a group is being collapsed.

    public boolean stableIds()

    Protected Methods

    protected abstract void bindChildView(View view, Context context, Cursor cursor, boolean isLastChild)

    Bind an existing view to the child data pointed to by cursor

    Parameters

    view Existing view, returned earlier by newChildView
    context Interface to application's global information
    cursor The cursor from which to get the data. The cursor is already moved to the correct position.
    isLastChild Whether the child is the last child within its group.

    protected abstract void bindGroupView(View view, Context context, Cursor cursor, boolean isExpanded)

    Bind an existing view to the group data pointed to by cursor.

    Parameters

    view Existing view, returned earlier by newGroupView.
    context Interface to application's global information
    cursor The cursor from which to get the data. The cursor is already moved to the correct position.
    isExpanded Whether the group is expanded.

    protected synchronized void deactivateChildrenCursorHelper(int groupPosition)

    Deactivates the Cursor and removes the helper from cache.

    Parameters

    groupPosition The group whose children Cursor and helper should be deactivated.

    protected abstract Cursor getChildrenCursor(Cursor groupCursor)

    Gets the Cursor for the children at the given group. Subclasses must implement this method to return the children data for a particular group.

    It is your responsibility to manage this Cursor through the Activity lifecycle. It is a good idea to use managedQuery(Uri, String[], String, String[], String) which will handle this for you. In some situations, the adapter will deactivate the Cursor on its own, but this will not always be the case, so please ensure the Cursor is properly managed.

    Parameters

    groupCursor The cursor pointing to the group whose children cursor should be returned

    Returns

    • The cursor for the children of a particular group

    protected synchronized MyCursorHelper getChildrenCursorHelper(int groupPosition)

    Gets the cursor helper for the children in the given group.

    Parameters

    groupPosition The group whose children will be returned

    Returns

    • The cursor helper for the children of the given group

    protected abstract View newChildView(Context context, Cursor cursor, boolean isLastChild, ViewGroup parent)

    Makes a new child view to hold the data pointed to by cursor.

    Parameters

    context Interface to application's global information
    cursor The cursor from which to get the data. The cursor is already moved to the correct position.
    isLastChild Whether the child is the last child within its group.
    parent The parent to which the new view is attached to

    Returns

    • the newly created view.

    protected abstract View newGroupView(Context context, Cursor cursor, boolean isExpanded, ViewGroup parent)

    Makes a new group view to hold the group data pointed to by cursor.

    Parameters

    context Interface to application's global information
    cursor The group cursor from which to get the data. The cursor is already moved to the correct position.
    isExpanded Whether the group is expanded.
    parent The parent to which the new view is attached to

    Returns

    • The newly created view.
    Build m5-rc15i - 10 Jun 2008 13:54