To dictate what the map can/should do, regardless of its contents, it needs some guidance!
It provides options that can be categorized into three main parts:
Initial positioning Defines the location of the map when it is first loaded
Permanent rules Defines restrictions that last throughout the map's lifetime
Event handling Defines methods that are called on specific map events
One part of MapOptions
responsibilities is to define how the map should be positioned when first loaded. There's two ways to do this (that are incompatible):
center
& zoom
Defines the center coordinates of the map and a zoom level
bounds
Defines an area with two/four coordinates that the viewport should fit to
It is possible to also set the map's rotation
in degrees, if you don't want it North (0°) facing initially.
Changing these properties after the map has already been built for the first time will have no effect: they only apply on initialisation.
To control the map programatically, use a MapController
: Controller.
One part of MapOptions
responsibilities is to define the restrictions and limitations of the map and what users can/cannot do with it.
You should check all the available options, but these are recommended for most maps:
maxZoom
(and minZoom
)
Limits how far the map can be zoomed by the user, to avoid showing empty tiles
maxBounds
Limits how far the map can be moved by the user to a coordinate-based boundary
interactiveFlags
- see InteractiveFlag
for available options
Limits what methods the user can interact with the map through (for example, preventing rotation)
keepAlive
If FlutterMap
is located inside a PageView
, ListView
or another complex lazy layout, set this true
to prevent the map from resetting to the #initial-positioning on rebuild
Instead of maxZoom
(or in addition to), consider setting maxNativeZoom
per TileLayer
instead, to allow tiles to scale (and lose quality) on the final zoom level, instead of setting a hard limit.