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Options

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

  • Defines methods that are called on specific map events

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Initial Positioning

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.

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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: .

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Permanent Rules

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 , 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

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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.

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Event Handling

When changes happen to FlutterMap's internal state, such as a change to the current position or zoom, it emits an event, some of which can be handled through callbacks, others of which can be handled through listening to a Stream.

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If building a custom layer (), consider using FlutterMapState directly instead.

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Through MapController

If you are doing any of the following, setup a MapController, and listen to its mapEventStream instead:

  • Capturing more than a couple of events & using the event's payload/data

  • Needing the events in a single Stream

  • Handling events that aren't available in the callbacks below ()

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Through MapOptions

The following callbacks are available:

  • onTap

  • onLongPress

  • onPositionChanged

interactiveFlags - see 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 on rebuild

  • onPointerDown/onPointerUp/onPointerHover/onPointerCancel

  • onMapReady Primarily used for a MapController's

  • onMapEvent (does not expose event data) Prefer

  • Event handling
    Controller
    all the available optionsarrow-up-right
    Creating New Layers
    Controllerchevron-right
    Through MapOptions
    InteractiveFlagarrow-up-right
    Initial Positioning
    Through MapController
    Usage In initState()
    MapOptions class - flutter_map library - Dart APIpub.devchevron-right
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