provide childAnimation as param (#247)

* provide childAnimation as param

* Fixed crash

_MyHomePageState is a SingleTickerProviderStateMixin but multiple tickers were created.
This was triggered when clicking on anything

* Changed passed argument

Just passing the animation Curve is sufficient, more efficient and just work

* Made example work

Also increased duration to see the actual animation

Co-authored-by: Luca <79720135+luca-colazzo@users.noreply.github.com>

example/lib/main.dart

@@ -42,7 +42,8 @@ class MyHomePage extends StatefulWidget {
   _MyHomePageState createState() => _MyHomePageState();
 }
 
-class _MyHomePageState extends State<MyHomePage> {
+class _MyHomePageState extends State<MyHomePage>
+    with TickerProviderStateMixin {
   var renderOverlay = true;
   var visible = true;
   var switchLabelPosition = false;
@@ -189,15 +190,17 @@ class _MyHomePageState extends State<MyHomePage> {
                                           vertical: 4, horizontal: 10),
                                       child: Align(
                                           alignment: Alignment.centerLeft,
-                                          child: Text( describeEnum(item).toUpperCase())),
+                                          child: Text(describeEnum(item)
+                                              .toUpperCase())),
                                     );
                                   }).toList();
                                 },
                                 items: SpeedDialDirection.values
                                     .toList()
                                     .map((item) {
                                   return DropdownMenuItem<SpeedDialDirection>(
-                                    child: Text(describeEnum(item).toUpperCase()),
+                                    child:
+                                        Text(describeEnum(item).toUpperCase()),
                                     value: item,
                                   );
                                 }).toList(),
@@ -388,8 +391,9 @@ class _MyHomePageState extends State<MyHomePage> {
           // activeForegroundColor: Colors.red,
           // activeBackgroundColor: Colors.blue,
           elevation: 8.0,
+          animationCurve: Curves.elasticInOut
           isOpenOnStart: false,
-          animationDuration: const Duration(milliseconds: 200),
+          animationDuration: const Duration(milliseconds: 1500),
           shape: customDialRoot
               ? const RoundedRectangleBorder()
               : const StadiumBorder(),

lib/src/speed_dial.dart

@@ -131,6 +131,9 @@ class SpeedDial extends StatefulWidget {
 
   final bool switchLabelPosition;
 
+  /// This is the animation of the child of the FAB, if specified it will animate b/w this
+  final Curve? animationCurve;
+
   const SpeedDial({
     Key? key,
     this.children = const [],
@@ -178,6 +181,7 @@ class SpeedDial extends StatefulWidget {
     this.childPadding = const EdgeInsets.symmetric(vertical: 5),
     this.spaceBetweenChildren,
     this.spacing,
+    this.animationCurve,
   }) : super(key: key);
 
   @override
@@ -276,6 +280,7 @@ class _SpeedDialState extends State<SpeedDial>
           layerLink: _layerLink,
           controller: _controller,
           toggleChildren: _toggleChildren,
+          animationCurve: widget.animationCurve,
         ),
       );
       if (widget.renderOverlay) {
@@ -459,31 +464,32 @@ class _ChildrensOverlay extends StatelessWidget {
     required this.dialKey,
     required this.controller,
     required this.toggleChildren,
+    this.childAnimation,
   }) : super(key: key);
 
   final SpeedDial widget;
   final GlobalKey<State<StatefulWidget>> dialKey;
   final LayerLink layerLink;
   final AnimationController controller;
   final Function toggleChildren;
+  final Curve? animationCurve;
+
   List<Widget> _getChildrenList() {
     return widget.children
         .map((SpeedDialChild child) {
           int index = widget.children.indexOf(child);
 
-          var childAnimation = Tween(begin: 0.0, end: 1.0).animate(
-            CurvedAnimation(
-              parent: controller,
-              curve: Interval(
-                index / widget.children.length,
-                1.0,
-                curve: Curves.ease,
-              ),
-            ),
-          );
-
           return AnimatedChild(
-            animation: childAnimation,
+            animation: Tween(begin: 0.0, end: 1.0).animate(
+                  CurvedAnimation(
+                    parent: controller,
+                    curve: Interval(
+                      index / widget.children.length,
+                      1.0,
+                      curve: widget.animationCurve ?? Curves.ease,
+                    ),
+                  ),
+                ),
             index: index,
             margin: widget.spaceBetweenChildren != null
                 ? EdgeInsets.fromLTRB(