NTPersistentCacheTileDataSource


@interface NTPersistentCacheTileDataSource : NTCacheTileDataSource

A tile data source that loads tiles from another tile data source and caches them in an offline sqlite database. Tiles will remain in the database even after the application is closed. The database contains table “persistent_cache” with the following fields: “tileId” (tile id), “compressed” (compressed tile image), “time” (the time the tile was cached in milliseconds from epoch). Default cache capacity is 50MB.

  • Constructs a PersistentCacheTileDataSource object from tile data source and a sqlite database. The sqlite database must be writable, if it doesn’t exist, an empty one will be created instead.

    Declaration

    Objective-C

    - (id)initWithDataSource:(NTTileDataSource *)dataSource
            databasePath:(NSString *)databasePath;

    Parameters

    dataSource

    The datasource to be cached.
    databasePath

    The path to the sqlite database, where the tiles will be cached.

  • Returns the state of cache only mode.

    Declaration

    Objective-C

    - (BOOL)isCacheOnlyMode;

    Return Value

    True when cache only mode is enabled, false otherwise.

  • Switches the datasource to ‘cache only’ mode or switches back from the mode. If enabled, tiles are loaded from the cache only and the original data source is not used. By default, cache only mode is off.

    Declaration

    Objective-C

    - (void)setCacheOnlyMode:(BOOL)enabled;

    Parameters

    enabled

    True when the mode should be enabled, false otherwise.

  • Starts downloading the specified area. The area will be stored in the cache. Note that is the area is too big or cache is already filled, subsequent downloaded tiles may push existing tile out of the cache.

    Declaration

    Objective-C

    - (void)startDownloadArea:(NTMapBounds *)mapBounds
                  minZoom:(int)minZoom
                  maxZoom:(int)maxZoom
     tileDownloadListener:(NTTileDownloadListener *)tileDownloadListener;

    Parameters

    mapBounds

    The bounds of the area to download. The coordinate system of the bounds must be the same as specified in the data source projection.
    minZoom

    The minimum zoom of the tiles to load.
    maxZoom

    The maximum zoom of the tiles to load.
    tileDownloadListener

    The tile download listener to use that will receive download related callbacks.

  • Stops all background downloader processes.

    Declaration

    Objective-C

    - (void)stopAllDownloads;

  • Returns the status of the cache database.

    Declaration

    Objective-C

    - (BOOL)isOpen;

    Return Value

    True if the persistent cache database is open and working, false otherwise.

  • Closes the cache database. The datasource will still work afterwards, but all requests will be directed to the original datasource.

    Declaration

    Objective-C

    - (void)close;

  • Undocumented

    Declaration

    Objective-C

    - (NTTileData *)loadTile:(NTMapTile *)mapTile;

  • Undocumented

    Declaration

    Objective-C

    -(NTTileData*)loadTileSwigExplicitNTPersistentCacheTileDataSource: (NTMapTile*)mapTile;

  • Undocumented

    Declaration

    Objective-C

    - (void)clear;

  • Undocumented

    Declaration

    Objective-C

    -(void)clearSwigExplicitNTPersistentCacheTileDataSource;

  • Undocumented

    Declaration

    Objective-C

    - (unsigned long)getCapacity;

  • Undocumented

    Declaration

    Objective-C

    -(unsigned long)getCapacitySwigExplicitNTPersistentCacheTileDataSource;

  • Undocumented

    Declaration

    Objective-C

    - (void)setCapacity:(unsigned long)capacityInBytes;

  • Undocumented

    Declaration

    Objective-C

    -(void)setCapacitySwigExplicitNTPersistentCacheTileDataSource: (unsigned long)capacityInBytes;

  • Undocumented

    Declaration

    Objective-C

    -(void)dealloc;