Creating New Tile Providers
One common requirement is a custom
TileProvider, and potentially a custom ImageProvider inside. This will allow your plugin to intercept all tile requests made by a map, and take your own action(s), before finally returning a tile.Some useful steps are below, but there are more properties of a
TileProvider that can be overridden.To create your own usable
TileProvider, the first step is making a class that extends the abstract class. It is not recommended to implement the base, as this will require overriding methods unnecessarily for most custom providers.class CustomTileProvider extends TileProvider {
// Add your own custom properties, methods, etc.
CustomTileProvider({
// Suitably initialise your own custom properties
super.headers, // Use the Dart 2.17 `super` syntax to initialise the base's header `Map`
})
}
The majority of custom
TileProviders will want to implement their own method to retrieve tiles. This is done by overriding the getImage method, and usually specifying your own ImageProvider, for example: @override
ImageProvider getImage(Coords<num> coords, TileLayerOptions options) =>
CustomImageProvider(
options: options,
coords: coords,
headers: {
...headers,
'User-Agent': headers['User-Agent'] == null
? '<pluginName> for flutter_map (unknown)'
: '<pluginName> for ${headers['User-Agent']}',
},
);
Notice that the 'User-Agent' header has been changed. This is recommended, as it helps further differentiate your plugin's traffic from vanilla 'flutter_map' traffic.
Some custom
TileProviders may want to change the way URLs for tiles are generated. Note that this is quite advanced usage. @override
String getTileUrl(Coords coords, TileLayerOptions options) {
// Custom generation
}
Last modified 3mo ago