FileDocCategorySizeDatePackage
LiveFolders.javaAPI DocAndroid 1.5 API11545Wed May 06 22:41:56 BST 2009android.provider

LiveFolders

public final class LiveFolders extends Object implements BaseColumns

A LiveFolder is a special folder whose content is provided by a {@link android.content.ContentProvider}. To create a live folder, two components are required:

  • An activity that can respond to the intent action {@link #ACTION_CREATE_LIVE_FOLDER}. The activity is responsible for creating the live folder.
  • A {@link android.content.ContentProvider} to provide the live folder items.

Lifecycle

When a user wants to create a live folder, the system looks for all activities with the intent filter action {@link #ACTION_CREATE_LIVE_FOLDER} and presents the list to the user. When the user chooses one of the activities, the activity is invoked with the {@link #ACTION_CREATE_LIVE_FOLDER} action. The activity then creates the live folder and passes it back to the system by setting it as an {@link android.app.Activity#setResult(int, android.content.Intent) activity result}. The live folder is described by a content provider URI, a name, an icon and a display mode. Finally, when the user opens the live folder, the system queries the content provider to retrieve the folder's content.

Setting up the live folder activity

The following code sample shows how to write an activity that creates a live fodler:

public static class MyLiveFolder extends Activity {
public static final Uri CONTENT_URI = Uri.parse("content://my.app/live");
Override
protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); final Intent intent = getIntent(); final String action = intent.getAction(); if (LiveFolders.ACTION_CREATE_LIVE_FOLDER.equals(action)) { setResult(RESULT_OK, createLiveFolder(this, CONTENT_URI, "My LiveFolder", R.drawable.ic_launcher_contacts_phones)); } else { setResult(RESULT_CANCELED); } finish(); } private static Intent createLiveFolder(Context context, Uri uri, String name, int icon) { final Intent intent = new Intent(); intent.setData(uri); intent.putExtra(LiveFolders.EXTRA_LIVE_FOLDER_NAME, name); intent.putExtra(LiveFolders.EXTRA_LIVE_FOLDER_ICON, Intent.ShortcutIconResource.fromContext(context, icon)); intent.putExtra(LiveFolders.EXTRA_LIVE_FOLDER_DISPLAY_MODE, LiveFolders.DISPLAY_MODE_LIST); return intent; } }

The live folder is described by an {@link android.content.Intent} as follows:

Component Type Description Required
URI URI The ContentProvider URI Yes
{@link #EXTRA_LIVE_FOLDER_NAME} Extra String The name of the live folder Yes
{@link #EXTRA_LIVE_FOLDER_ICON} Extra {@link android.content.Intent.ShortcutIconResource} The icon of the live folder Yes
{@link #EXTRA_LIVE_FOLDER_DISPLAY_MODE} Extra int The display mode of the live folder. The value must be either {@link #DISPLAY_MODE_GRID} or {@link #DISPLAY_MODE_LIST}. Yes
{@link #EXTRA_LIVE_FOLDER_BASE_INTENT} Extra Intent When the user clicks an item inside a live folder, the system will either fire the intent associated with that item or, if present, the live folder's base intent with the id of the item appended to the base intent's URI. No

Setting up the content provider

The live folder's content provider must, upon query, return a {@link android.database.Cursor} whose columns match the following names:

Column Type Description Required
{@link #NAME} String The name of the item Yes
{@link #DESCRIPTION} String The description of the item. The description is ignored when the live folder's display mode is {@link #DISPLAY_MODE_GRID}. No
{@link #INTENT} {@link android.content.Intent} The intent to fire when the item is clicked. Ignored when the live folder defines a base intent. No
{@link #ICON_BITMAP} Bitmap The icon for the item. When this column value is not null, the values for the columns {@link #ICON_PACKAGE} and {@link #ICON_RESOURCE} must be null. No
{@link #ICON_PACKAGE} String The package of the item's icon. When this value is not null, the value for the column {@link #ICON_RESOURCE} must be specified and the value for the column {@link #ICON_BITMAP} must be null. No
{@link #ICON_RESOURCE} String The resource name of the item's icon. When this value is not null, the value for the column {@link #ICON_PACKAGE} must be specified and the value for the column {@link #ICON_BITMAP} must be null. No

Fields Summary
public static final String
NAME

Content provider column.

Name of the live folder item.

Required.

Type: String.

public static final String
DESCRIPTION

Content provider column.

Description of the live folder item. This value is ignored if the live folder's display mode is {@link LiveFolders#DISPLAY_MODE_GRID}.

Optional.

Type: String.

public static final String
INTENT

Content provider column.

Intent of the live folder item.

Optional if the live folder has a base intent.

Type: {@link android.content.Intent}.

public static final String
ICON_BITMAP

Content provider column.

Icon of the live folder item, as a custom bitmap.

Optional.

Type: {@link android.graphics.Bitmap}.

public static final String
ICON_PACKAGE

Content provider column.

Package where to find the icon of the live folder item. This value can be obtained easily using {@link android.content.Intent.ShortcutIconResource#fromContext(android.content.Context, int)}.

Optional.

Type: String.

public static final String
ICON_RESOURCE

Content provider column.

Resource name of the live folder item. This value can be obtained easily using {@link android.content.Intent.ShortcutIconResource#fromContext(android.content.Context, int)}.

Optional.

Type: String.

public static final int
DISPLAY_MODE_GRID
Displays a live folder's content in a grid.
public static final int
DISPLAY_MODE_LIST
Displays a live folder's content in a list.
public static final String
EXTRA_LIVE_FOLDER_NAME
The name of the extra used to define the name of a live folder.
public static final String
EXTRA_LIVE_FOLDER_ICON
The name of the extra used to define the icon of a live folder.
public static final String
EXTRA_LIVE_FOLDER_DISPLAY_MODE
The name of the extra used to define the display mode of a live folder.
public static final String
EXTRA_LIVE_FOLDER_BASE_INTENT
The name of the extra used to define the base Intent of a live folder.
public static final String
ACTION_CREATE_LIVE_FOLDER
Activity Action: Creates a live folder.

Input: Nothing.

Output: An Intent representing the live folder. The intent must contain four extras: EXTRA_LIVE_FOLDER_NAME (value: String), EXTRA_LIVE_FOLDER_ICON (value: ShortcutIconResource), EXTRA_LIVE_FOLDER_URI (value: String) and EXTRA_LIVE_FOLDER_DISPLAY_MODE (value: int). The Intent can optionnally contain EXTRA_LIVE_FOLDER_BASE_INTENT (value: Intent).

Constructors Summary
private LiveFolders()


      
    
Methods Summary