Added BottomAppBar docked FloatingActionButtonLocations (#16167)

* Added BottomAppBar docked FloationActionButtonLocations

* Moved the startTop FloatingActionButtonLocation to the demo

* fixed a typo

examples/flutter_gallery/lib/demo/material/fab_motion_demo.dart

@@ -19,9 +19,9 @@ class FabMotionDemo extends StatefulWidget {
 
 class _FabMotionDemoState extends State<FabMotionDemo> {
   static const List<FloatingActionButtonLocation> _floatingActionButtonLocations = const <FloatingActionButtonLocation>[
-    FloatingActionButtonLocation.endFloat, 
+    FloatingActionButtonLocation.endFloat,
     FloatingActionButtonLocation.centerFloat,
-    const _TopStartFloatingActionButtonLocation(),
+    const _StartTopFloatingActionButtonLocation(),
   ];
 
   bool _showFab = true;
@@ -29,25 +29,25 @@ class _FabMotionDemoState extends State<FabMotionDemo> {
 
   @override
   Widget build(BuildContext context) {
-    final Widget floatingActionButton = _showFab 
+    final Widget floatingActionButton = _showFab
       ? new Builder(builder: (BuildContext context) {
         // We use a widget builder here so that this inner context can find the Scaffold.
         // This makes it possible to show the snackbar.
         return new FloatingActionButton(
           backgroundColor: Colors.yellow.shade900,
           onPressed: () => _showSnackbar(context),
-          child: const Icon(Icons.add), 
+          child: const Icon(Icons.add),
         );
-      }) 
+      })
       : null;
     return new Scaffold(
       appBar: new AppBar(
-        title: const Text('FAB Location'), 
+        title: const Text('FAB Location'),
         // Add 48dp of space onto the bottom of the appbar.
         // This gives space for the top-start location to attach to without
         // blocking the 'back' button.
         bottom: const PreferredSize(
-          preferredSize: const Size.fromHeight(48.0), 
+          preferredSize: const Size.fromHeight(48.0),
           child: const SizedBox(),
         ),
       ),
@@ -93,8 +93,8 @@ class _FabMotionDemoState extends State<FabMotionDemo> {
 
 // Places the Floating Action Button at the top of the content area of the
 // app, on the border between the body and the app bar.
-class _TopStartFloatingActionButtonLocation extends FloatingActionButtonLocation {
-  const _TopStartFloatingActionButtonLocation();
+class _StartTopFloatingActionButtonLocation extends FloatingActionButtonLocation {
+  const _StartTopFloatingActionButtonLocation();
 
   @override
   Offset getOffset(ScaffoldPrelayoutGeometry scaffoldGeometry) {
@@ -130,7 +130,7 @@ class _TopStartFloatingActionButtonLocation extends FloatingActionButtonLocation
         fabX = startPadding;
         break;
     }
-    // Finally, we'll place the Y coordinate for the Floating Action Button 
+    // Finally, we'll place the Y coordinate for the Floating Action Button
     // at the top of the content body.
     //
     // We want to place the middle of the Floating Action Button on the

packages/flutter/test/material/floating_action_button_location_test.dart

@@ -7,53 +7,31 @@ import 'package:flutter/material.dart';
 import 'package:flutter_test/flutter_test.dart';
 
 void main() {
-  group('Floating action button positioner', () {
-    Widget build(FloatingActionButton fab, FloatingActionButtonLocation fabLocation, [_GeometryListener listener]) {
-      return new Directionality(
-        textDirection: TextDirection.ltr,
-        child: new MediaQuery(
-          data: const MediaQueryData(
-            viewInsets: const EdgeInsets.only(bottom: 200.0),
-          ),
-          child: new Scaffold(
-            appBar: new AppBar(title: const Text('FabLocation Test')),
-            floatingActionButtonLocation: fabLocation,
-            floatingActionButton: fab,
-            body: listener,
-          ),
-        ),
-      );
-    }
-
-    const FloatingActionButton fab1 = const FloatingActionButton(
-        onPressed: null,
-        child: const Text('1'),
-      );
-
+  group('Basic floating action button locations', () {
     testWidgets('still animates motion when the floating action button is null', (WidgetTester tester) async {
-      await tester.pumpWidget(build(null, null));
+      await tester.pumpWidget(buildFrame(fab: null, location: null));
 
       expect(find.byType(FloatingActionButton), findsNothing);
       expect(tester.binding.transientCallbackCount, 0);
 
-      await tester.pumpWidget(build(null, FloatingActionButtonLocation.endFloat));
+      await tester.pumpWidget(buildFrame(fab: null, location: FloatingActionButtonLocation.endFloat));
 
       expect(find.byType(FloatingActionButton), findsNothing);
       expect(tester.binding.transientCallbackCount, greaterThan(0));
 
-      await tester.pumpWidget(build(null, FloatingActionButtonLocation.centerFloat));
+      await tester.pumpWidget(buildFrame(fab: null, location: FloatingActionButtonLocation.centerFloat));
 
       expect(find.byType(FloatingActionButton), findsNothing);
       expect(tester.binding.transientCallbackCount, greaterThan(0));
     });
 
     testWidgets('moves fab from center to end and back', (WidgetTester tester) async {
-      await tester.pumpWidget(build(fab1, FloatingActionButtonLocation.endFloat));
+      await tester.pumpWidget(buildFrame(location: FloatingActionButtonLocation.endFloat));
 
       expect(tester.getCenter(find.byType(FloatingActionButton)), const Offset(756.0, 356.0));
       expect(tester.binding.transientCallbackCount, 0);
 
-      await tester.pumpWidget(build(fab1, FloatingActionButtonLocation.centerFloat));
+      await tester.pumpWidget(buildFrame(location: FloatingActionButtonLocation.centerFloat));
 
       expect(tester.binding.transientCallbackCount, greaterThan(0));
 
@@ -62,8 +40,8 @@ void main() {
       expect(tester.getCenter(find.byType(FloatingActionButton)), const Offset(400.0, 356.0));
       expect(tester.binding.transientCallbackCount, 0);
 
-      await tester.pumpWidget(build(fab1, FloatingActionButtonLocation.endFloat));
-      
+      await tester.pumpWidget(buildFrame(location: FloatingActionButtonLocation.endFloat));
+
       expect(tester.binding.transientCallbackCount, greaterThan(0));
 
       await tester.pumpAndSettle();
@@ -73,11 +51,11 @@ void main() {
     });
 
     testWidgets('moves to and from custom-defined positions', (WidgetTester tester) async {
-      await tester.pumpWidget(build(fab1, _kTopStartFabLocation));
+      await tester.pumpWidget(buildFrame(location: const _StartTopFloatingActionButtonLocation()));
 
       expect(tester.getCenter(find.byType(FloatingActionButton)), const Offset(44.0, 56.0));
 
-      await tester.pumpWidget(build(fab1, FloatingActionButtonLocation.centerFloat));
+      await tester.pumpWidget(buildFrame(location: FloatingActionButtonLocation.centerFloat));
       expect(tester.binding.transientCallbackCount, greaterThan(0));
 
       await tester.pumpAndSettle();
@@ -85,8 +63,8 @@ void main() {
       expect(tester.getCenter(find.byType(FloatingActionButton)), const Offset(400.0, 356.0));
       expect(tester.binding.transientCallbackCount, 0);
 
-      await tester.pumpWidget(build(fab1, _kTopStartFabLocation));
-      
+      await tester.pumpWidget(buildFrame(location: const _StartTopFloatingActionButtonLocation()));
+
       expect(tester.binding.transientCallbackCount, greaterThan(0));
 
       await tester.pumpAndSettle();
@@ -122,23 +100,76 @@ void main() {
 
       // We'll listen to the Scaffold's geometry for any 'jumps' to a size of 1 to detect changes in the size and rotation of the fab.
       // Creating a scaffold with the fab at endFloat
-      await tester.pumpWidget(build(fab1, FloatingActionButtonLocation.endFloat, geometryListener));
-      
+      await tester.pumpWidget(buildFrame(location: FloatingActionButtonLocation.endFloat, listener: geometryListener));
+
       listenerState = tester.state(find.byType(_GeometryListener));
       listenerState.geometryListenable.addListener(check);
-      
+
       // Moving the fab to centerFloat'
-      await tester.pumpWidget(build(fab1, FloatingActionButtonLocation.centerFloat, geometryListener));
+      await tester.pumpWidget(buildFrame(location: FloatingActionButtonLocation.centerFloat, listener: geometryListener));
       await tester.pumpAndSettle();
 
       // Moving the fab to the top start after finishing the previous motion
-      await tester.pumpWidget(build(fab1, _kTopStartFabLocation, geometryListener));
+      await tester.pumpWidget(buildFrame(location: const _StartTopFloatingActionButtonLocation(), listener: geometryListener));
 
       // Interrupting motion to move to the end float
-      await tester.pumpWidget(build(fab1, FloatingActionButtonLocation.endFloat, geometryListener));
+      await tester.pumpWidget(buildFrame(location: FloatingActionButtonLocation.endFloat, listener: geometryListener));
       await tester.pumpAndSettle();
     });
+  });
+
+  testWidgets('Docked floating action button locations', (WidgetTester tester) async {
+    await tester.pumpWidget(
+      buildFrame(
+        location: FloatingActionButtonLocation.endDocked,
+        bab: const SizedBox(height: 100.0),
+        viewInsets: EdgeInsets.zero,
+      ),
+    );
+
+    // Scaffold 800x600, FAB is 56x56, BAB is 800x100, FAB's center is
+    // at the top of the BAB.
+    expect(tester.getCenter(find.byType(FloatingActionButton)), const Offset(756.0, 500.0));
 
+    await tester.pumpWidget(
+      buildFrame(
+        location: FloatingActionButtonLocation.centerDocked,
+        bab: const SizedBox(height: 100.0),
+        viewInsets: EdgeInsets.zero,
+      ),
+    );
+    await tester.pumpAndSettle();
+    expect(tester.getCenter(find.byType(FloatingActionButton)), const Offset(400.0, 500.0));
+
+
+    await tester.pumpWidget(
+      buildFrame(
+        location: FloatingActionButtonLocation.endDocked,
+        bab: const SizedBox(height: 100.0),
+        viewInsets: EdgeInsets.zero,
+      ),
+    );
+    await tester.pumpAndSettle();
+    expect(tester.getCenter(find.byType(FloatingActionButton)), const Offset(756.0, 500.0));
+  });
+
+  testWidgets('Docked floating action button locations: no BAB, small BAB', (WidgetTester tester) async {
+    await tester.pumpWidget(
+      buildFrame(
+        location: FloatingActionButtonLocation.endDocked,
+        viewInsets: EdgeInsets.zero,
+      ),
+    );
+    expect(tester.getCenter(find.byType(FloatingActionButton)), const Offset(756.0, 572.0));
+
+    await tester.pumpWidget(
+      buildFrame(
+        location: FloatingActionButtonLocation.endDocked,
+        bab: const SizedBox(height: 16.0),
+        viewInsets: EdgeInsets.zero,
+      ),
+    );
+    expect(tester.getCenter(find.byType(FloatingActionButton)), const Offset(756.0, 572.0));
   });
 }
 
@@ -169,7 +200,7 @@ class _GeometryListenerState extends State<_GeometryListener> {
 
     if (geometryListenable != null)
       geometryListenable.removeListener(onGeometryChanged);
-    
+
     geometryListenable = newListenable;
     geometryListenable.addListener(onGeometryChanged);
     cache = new _GeometryCachePainter(geometryListenable);
@@ -201,15 +232,50 @@ class _GeometryCachePainter extends CustomPainter {
   }
 }
 
-const _TopStartFabLocation _kTopStartFabLocation = const _TopStartFabLocation();
+Widget buildFrame({
+  FloatingActionButton fab: const FloatingActionButton(
+    onPressed: null,
+    child: const Text('1'),
+  ),
+  FloatingActionButtonLocation location,
+  _GeometryListener listener,
+  TextDirection textDirection: TextDirection.ltr,
+  EdgeInsets viewInsets: const EdgeInsets.only(bottom: 200.0),
+  Widget bab,
+}) {
+  return new Directionality(
+    textDirection: textDirection,
+    child: new MediaQuery(
+      data: new MediaQueryData(viewInsets: viewInsets),
+      child: new Scaffold(
+        appBar: new AppBar(title: const Text('FabLocation Test')),
+        floatingActionButtonLocation: location,
+        floatingActionButton: fab,
+        bottomNavigationBar: bab,
+        body: listener,
+      ),
+    ),
+  );
+}
 
-class _TopStartFabLocation extends FloatingActionButtonLocation {
-  const _TopStartFabLocation();
+class _StartTopFloatingActionButtonLocation extends FloatingActionButtonLocation {
+  const _StartTopFloatingActionButtonLocation();
 
   @override
   Offset getOffset(ScaffoldPrelayoutGeometry scaffoldGeometry) {
-    final double fabX = 16.0 + scaffoldGeometry.minInsets.left;
+    double fabX;
+    assert(scaffoldGeometry.textDirection != null);
+    switch (scaffoldGeometry.textDirection) {
+      case TextDirection.rtl:
+        final double startPadding = kFloatingActionButtonMargin + scaffoldGeometry.minInsets.right;
+        fabX = scaffoldGeometry.scaffoldSize.width - scaffoldGeometry.floatingActionButtonSize.width - startPadding;
+        break;
+      case TextDirection.ltr:
+        final double startPadding = kFloatingActionButtonMargin + scaffoldGeometry.minInsets.left;
+        fabX = startPadding;
+        break;
+    }
     final double fabY = scaffoldGeometry.contentTop - (scaffoldGeometry.floatingActionButtonSize.height / 2.0);
     return new Offset(fabX, fabY);
   }
-}
+}
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