flutter_map_polywidget

flutter_map_polywidget is a flutter_map plugin for displaying any widget on the map.

polywidget.webm

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Features

  • choose the location and size of the desired area and display any widget you want
  • define the location by
    • center, width, height and angle
    • two exact and one approximated point
  • constrain your custom widget so that it does not get too big or too small when you zoom in or out
  • define whether the widget should rotate with the users view, restrict it to one orientation or disable rotation completely

Getting started

Add flutter_map_polywidget to your pubspec.yaml:

dependencies:
  flutter_map_polywidget: any # or latest verion

Usage

Start by adding a PolyWidgetLayer to your map:

FlutterMap(
  children: [
    ...
    PolyWidgetLayer(
      polyWidgets: [
        ...
      ],
    ),
  ],
),

Add PolyWidget widgets inside your PolyWidgetLayer. PolyWidgets can be created in two ways.

First, by defining the center location, the width, the height and the angle of your widget:

PolyWidget(
  center: LatLng(50.933465, 6.875109),
  widthInMeters: 100,
  heightInMeters: 200,
  angle: 90,
  child: ...,
),

Second, by defining three corners of the desired widget on the map. The first and second corners are fixed and will be used to define the width and angle of your widget. The third corner is only fixed if it is placed in a 90° angle from the second corner. Otherwise the distance from the second to the third corner is used to calculate the actual third corner. All three corners are used to calculate the center location.

PolyWidget.threePoints(
  pointA: LatLng(50.936614, 6.876283),
  pointB: LatLng(50.936498, 6.877663),
  approxPointC: LatLng(50.935312, 6.877419),
  child: ...,
),

Constraints

By default, your widget is unconstrained. The more you zoom out, the smaller your widget gets. If your widget needs a minimum size, this can result in layout errors. To prevent that, you can define constraints on your polywidget. This wraps your widget in a FittedBox and ensures, that it fits your constraints.

PolyWidget(
  ...,
  constraints: BoxConstraints(
    minWidth: 250,
    maxWidth: 350,
  ),
  child: ...,
),

polywidget_with_constraints.webm

Disable rotation

By default, your widget rotates automatically so it lines up with the current rotation of the map. To disable that, set noRotation to true:

PolyWidget(
  ...,
  noRotation: true,
  child: ...,
),

Force orientation

If you want your widget to only rotate to portrait or landscape orientation, you can do that by defining forceOrientation:

PolyWidget(
  ...,
  forceOrientation: Orientation.landscape, //or Orientation.portrait
  child: ...,
),

Example

You can find the example shown in the showcase video in /example.

Libraries

flutter_map_polywidget