flutter_map Integration

Stores also have the method getTileProvider(). This is the point of integration with flutter_map, providing browse caching through a custom image provider, and can be used as so:

import 'package:flutter_map/flutter_map.dart';

TileLayer(
    // urlTemplate: 'https://tile.openstreetmap.org/{z}/{x}/{y}.png',
    // userAgentPackageName: 'com.example.app',
    tileProvider: FMTC.instance('storeName').getTileProvider(),
    // Other parameters as normal
),

Tile Provider Settings

This method (and others) optionally take a FMTCTileProviderSettings. These configure the behaviour of the tile provider. Defaults to the settings specified in the Global Settings, or the package default (see table below) if that is not specified.

FMTCTileProviderSettings can take the following arguments:

Parameter

behavior: CacheBehavior

Description

Determine the logic used during handling storage and retrieval of browse caching

Default

CacheBehavior.cacheFirst

Parameter

cachedValidDuration: Duration

Description

Length of time a tile remains valid, after which it must be fetched again (ignored in onlineFirst mode)

Default

const Duration(days: 16)

Parameter

maxStoreLength: int

Description

Maximum number of tiles allowed in a cache store (deletes oldest tile)

Default

0: disabled

Parameter

obscuredQueryParams: List<String>

Description

See Obscuring Query Parameters

Default

[]: empty

Cache Behavior

This enumerable contains 3 values, which are used to dictate which logic should be used to store and retrieve tiles from the store.

Value	Explanation
cacheFirst	Get tiles from the local cache if possible. Only uses the Internet if it doesn't exist, or to update it if it has expired.
onlineFirst	Get tiles from the Internet if possible. Updates every cached tile every time it is fetched (ignores expiry).
cacheOnly	Only get tiles from the local cache, and throw an error if not found. Recommended for dedicated offline modes.

Obscuring Query Parameters

A backport of this functionality to v6 is also available - see this branch on GitHub, and install it through GitHub: From github.com.

If you've got a value (such as a token or a key) in the URL's query parameters (the key-value pairs list found after the '?') that you need to keep secret or that changes frequently, make use of obscuredQueryParams.

Pass it the list of query keys who's values need to be removed/omitted/obscured in storage. For example, 'api_key' would remove the 'api_key', and any other characters until the next key-value pair, or the end of the URL, as seen below:

https://tile.myserver.com/{z}/{x}/{y}?api_key=001239876&mode=dark
https://tile.myserver.com/{z}/{x}/{y}?&mode=dark

Since v3, FMTC relies on URL equality to find tiles within a store during browsing. This method is therefore necessary in cases where a token changes periodically.

Check If A Tile Is Cached

checkTileCached method - FMTCTileProvider class - flutter_map_tile_caching library - Dart API