move gesture detection into map widget

flutter_map/lib/flutter_map.dart

@@ -4,6 +4,7 @@ import 'package:flutter/widgets.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
 import 'package:flutter_map/src/core/point.dart';
+import 'package:flutter_map/src/gestures/gestures.dart';
 import 'package:flutter_map/src/map/map.dart';
 
 export 'src/layer/layer.dart';
@@ -20,7 +21,8 @@ class FlutterMap extends StatefulWidget {
   }
 }
 
-class _FlutterMapState extends State<FlutterMap> {
+class _FlutterMapState extends State<FlutterMap>
+    with MapGestureMixin, SingleTickerProviderStateMixin {
   MapOptions get options => widget.options;
   MapState mapState;
 
@@ -34,9 +36,16 @@ class _FlutterMapState extends State<FlutterMap> {
         builder: (BuildContext context, BoxConstraints constraints) {
       mapState.size =
           new Point<double>(constraints.maxWidth, constraints.maxHeight);
-      return new Container(
-        child: new Stack(
-          children: widget.layers.map(_createLayer).toList(),
+      var layerWidgets = widget.layers.map(_createLayer).toList();
+      return new GestureDetector(
+        onScaleStart: handleScaleStart,
+        onScaleUpdate: handleScaleUpdate,
+        onScaleEnd: handleScaleEnd,
+        onTapUp: handleTapUp,
+        child: new Container(
+          child: new Stack(
+            children: layerWidgets,
+          ),
         ),
       );
     });

flutter_map/lib/src/gestures/gestures.dart

@@ -0,0 +1,130 @@
+import 'dart:math' as math;
+
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+import 'package:flutter_map/src/core/point.dart';
+import 'package:latlong/latlong.dart';
+import 'package:flutter_map/flutter_map.dart';
+
+abstract class MapGestureMixin extends State<FlutterMap>
+    with SingleTickerProviderStateMixin {
+  static const double _kMinFlingVelocity = 800.0;
+
+  LatLng _mapCenterStart;
+  double _mapZoomStart;
+  Point _focalPointStart;
+
+  AnimationController _controller;
+  Animation<Offset> _flingAnimation;
+  Offset _animationOffset = Offset.zero;
+
+  FlutterMap get widget;
+  MapState get mapState;
+  MapState get map => mapState;
+  MapOptions get options;
+
+  void initState() {
+    super.initState();
+    _controller = new AnimationController(vsync: this)
+      ..addListener(_handleFlingAnimation);
+  }
+
+  void handleScaleStart(ScaleStartDetails details) {
+    setState(() {
+      _mapZoomStart = map.zoom;
+      _mapCenterStart = map.center;
+
+      // Get the widget's offset
+      var renderObject = context.findRenderObject() as RenderBox;
+      var boxOffset = renderObject.localToGlobal(Offset.zero);
+
+      // determine the focal point within the widget
+      var localFocalPoint = _offsetToPoint(details.focalPoint - boxOffset);
+      _focalPointStart = localFocalPoint;
+
+      _controller.stop();
+    });
+  }
+
+  void handleScaleUpdate(ScaleUpdateDetails details) {
+    setState(() {
+      var dScale = details.scale;
+      for (var i = 0; i < 2; i++) {
+        dScale = math.sqrt(dScale);
+      }
+      var renderObject = context.findRenderObject() as RenderBox;
+      var boxOffset = renderObject.localToGlobal(Offset.zero);
+
+      // Draw the focal point
+      var localFocalPoint = _offsetToPoint(details.focalPoint - boxOffset);
+
+      // get the focal point in global coordinates
+      var dFocalPoint = localFocalPoint - _focalPointStart;
+
+      var focalCenterDistance = localFocalPoint - (map.size / 2);
+      var newCenter = map.project(_mapCenterStart) +
+          focalCenterDistance.multiplyBy(1 - 1 / dScale) -
+          dFocalPoint;
+
+      var offsetPt = newCenter - map.project(_mapCenterStart);
+      _animationOffset = _pointToOffset(offsetPt);
+
+      var newZoom = _mapZoomStart * dScale;
+      map.move(map.unproject(newCenter), newZoom);
+    });
+  }
+
+  void handleScaleEnd(ScaleEndDetails details) {
+    final double magnitude = details.velocity.pixelsPerSecond.distance;
+    if (magnitude < _kMinFlingVelocity) return;
+    final Offset direction = details.velocity.pixelsPerSecond / magnitude;
+    final double distance = (Offset.zero & context.size).shortestSide;
+    _flingAnimation = new Tween<Offset>(
+            begin: _animationOffset,
+            end: _animationOffset - direction * distance)
+        .animate(_controller);
+    _controller
+      ..value = 0.0
+      ..fling(velocity: magnitude / 1000.0);
+  }
+
+  void handleTapUp(TapUpDetails details) {
+    if (options.onTap == null) {
+      return;
+    }
+    // Get the widget's offset
+    var renderObject = context.findRenderObject() as RenderBox;
+    var boxOffset = renderObject.localToGlobal(Offset.zero);
+    var width = renderObject.size.width;
+    var height = renderObject.size.height;
+
+    // convert the point to global coordinates
+    var localPoint = _offsetToPoint(details.globalPosition - boxOffset);
+    var localPointCenterDistance =
+        new Point((width / 2) - localPoint.x, (height / 2) - localPoint.y);
+    var mapCenter = map.project(map.center);
+    var point = mapCenter - localPointCenterDistance;
+    var latlng = map.unproject(point);
+
+    // emit the event
+    options.onTap(latlng);
+  }
+
+  void _handleFlingAnimation() {
+    setState(() {
+      _animationOffset = _flingAnimation.value;
+      var newCenterPoint = map.project(_mapCenterStart) +
+          new Point(_animationOffset.dx, _animationOffset.dy);
+      var newCenter = map.unproject(newCenterPoint);
+      map.move(newCenter, map.zoom);
+    });
+  }
+
+  Point _offsetToPoint(Offset offset) {
+    return new Point(offset.dx, offset.dy);
+  }
+
+  Offset _pointToOffset(Point point) {
+    return new Offset(point.x, point.y);
+  }
+}

flutter_map/lib/src/layer/tile_layer.dart

@@ -1,6 +1,5 @@
 import 'dart:typed_data';
 
-import 'dart:math' as math;
 import 'package:flutter/material.dart';
 import 'package:flutter/widgets.dart';
 import 'package:latlong/latlong.dart';
@@ -43,8 +42,7 @@ class TileLayer extends StatefulWidget {
   }
 }
 
-class _TileLayerState extends State<TileLayer>
-    with SingleTickerProviderStateMixin {
+class _TileLayerState extends State<TileLayer> {
   MapState get map => widget.mapState;
   TileLayerOptions get options => widget.options;
   Bounds _globalTileRange;
@@ -59,8 +57,6 @@ class _TileLayerState extends State<TileLayer>
   void initState() {
     super.initState();
     _resetView();
-    _controller = new AnimationController(vsync: this)
-      ..addListener(_handleFlingAnimation);
   }
 
   String getTileUrl(Coords coords) {
@@ -273,106 +269,14 @@ class _TileLayerState extends State<TileLayer>
       tileWidgets.add(_createTileWidget(tile.coords));
     }
 
-    return new GestureDetector(
-      onScaleStart: _handleScaleStart,
-      onScaleUpdate: _handleScaleUpdate,
-      onScaleEnd: _handleScaleEnd,
-      child: new Container(
-        child: new Stack(
-          children: tileWidgets,
-        ),
-        color: Colors.grey[300],
+    return new Container(
+      child: new Stack(
+        children: tileWidgets,
       ),
+      color: Colors.grey[300],
     );
   }
 
-  Point _offsetToPoint(Offset offset) {
-    return new Point(offset.dx, offset.dy);
-  }
-
-  Offset _pointToOffset(Point point) {
-    return new Offset(point.x, point.y);
-  }
-
-  LatLng _mapCenterStart;
-  double _mapZoomStart;
-  Point _focalPointStart;
-
-  Offset _animationOffset = Offset.zero;
-
-  void _handleScaleStart(ScaleStartDetails details) {
-    setState(() {
-      _mapZoomStart = map.zoom;
-      _mapCenterStart = map.center;
-
-      // Get the widget's offset
-      var renderObject = context.findRenderObject() as RenderBox;
-      var boxOffset = renderObject.localToGlobal(Offset.zero);
-
-      // determine the focal point within the widget
-      var localFocalPoint = _offsetToPoint(details.focalPoint - boxOffset);
-      _focalPointStart = localFocalPoint;
-
-      _controller.stop();
-    });
-  }
-
-  void _handleScaleUpdate(ScaleUpdateDetails details) {
-    setState(() {
-      var dScale = details.scale;
-      for (var i = 0; i < 2; i++) {
-        dScale = math.sqrt(dScale);
-      }
-      var renderObject = context.findRenderObject() as RenderBox;
-      var boxOffset = renderObject.localToGlobal(Offset.zero);
-
-      // Draw the focal point
-      var localFocalPoint = _offsetToPoint(details.focalPoint - boxOffset);
-
-      // get the focal point in global coordinates
-      var dFocalPoint = localFocalPoint - _focalPointStart;
-
-      var focalCenterDistance = localFocalPoint - (map.size / 2);
-      var newCenter = map.project(_mapCenterStart) +
-          focalCenterDistance.multiplyBy(1 - 1 / dScale) -
-          dFocalPoint;
-
-      var offsetPt = newCenter - map.project(_mapCenterStart);
-      _animationOffset = _pointToOffset(offsetPt);
-
-      var newZoom = _mapZoomStart * dScale;
-      map.move(map.unproject(newCenter), newZoom);
-    });
-  }
-
-  AnimationController _controller;
-  Animation<Offset> _flingAnimation;
-  static const double _kMinFlingVelocity = 800.0;
-
-  void _handleScaleEnd(ScaleEndDetails details) {
-    final double magnitude = details.velocity.pixelsPerSecond.distance;
-    if (magnitude < _kMinFlingVelocity) return;
-    final Offset direction = details.velocity.pixelsPerSecond / magnitude;
-    final double distance = (Offset.zero & context.size).shortestSide;
-    _flingAnimation = new Tween<Offset>(
-            begin: _animationOffset,
-            end: _animationOffset - direction * distance)
-        .animate(_controller);
-    _controller
-      ..value = 0.0
-      ..fling(velocity: magnitude / 1000.0);
-  }
-
-  void _handleFlingAnimation() {
-    setState(() {
-      _animationOffset = _flingAnimation.value;
-      var newCenterPoint = map.project(_mapCenterStart) +
-          new Point(_animationOffset.dx, _animationOffset.dy);
-      var newCenter = map.unproject(newCenterPoint);
-      map.move(newCenter, map.zoom);
-    });
-  }
-
   Bounds _getTiledPixelBounds(LatLng center) {
     var mapZoom = map.zoom;
     var scale = map.getZoomScale(mapZoom, this._tileZoom);

flutter_map/lib/src/map/map.dart

@@ -6,13 +6,17 @@ import 'package:flutter_map/src/core/bounds.dart';
 import 'package:flutter_map/src/core/point.dart';
 import 'package:flutter_map/src/geo/crs/crs.dart';
 
+typedef TapCallback(LatLng point);
+
 class MapOptions {
   final Crs crs;
   final double zoom;
   final double minZoom;
   final double maxZoom;
   final List<LayerOptions> layers;
   final bool debug;
+  final bool interactive;
+  final TapCallback onTap;
   LatLng center;
 
   MapOptions({
@@ -23,24 +27,27 @@ class MapOptions {
     this.maxZoom,
     this.layers,
     this.debug = false,
+    this.interactive = true,
+    this.onTap,
   }) {
     if (center == null) center = new LatLng(50.5, 30.51);
   }
 }
 
 class MapState {
   final MapOptions options;
-  final StreamController<Null> _onMovedSink;
+  final StreamController<Null> _onMoveSink;
+
   double zoom;
   LatLng _lastCenter;
   Point _pixelOrigin;
   bool _initialized = false;
 
-  MapState(this.options) : _onMovedSink = new StreamController.broadcast();
+  MapState(this.options) : _onMoveSink = new StreamController.broadcast();
 
   Point _size;
 
-  Stream<Null> get onMoved => _onMovedSink.stream;
+  Stream<Null> get onMoved => _onMoveSink.stream;
 
   Point get size => _size;
   set size(Point s) {
@@ -66,7 +73,7 @@ class MapState {
     this.zoom = zoom;
     this._lastCenter = center;
     this._pixelOrigin = this.getNewPixelOrigin(center);
-    _onMovedSink.add(null);
+    _onMoveSink.add(null);
   }
 
   LatLng getCenter() {