switch scale mode if 3 fingers tap

flutter_hbb/lib/drag.dart

@@ -0,0 +1,104 @@
+import 'package:flutter/gestures.dart';
+
+class MultiTouchGestureRecognizer extends MultiTapGestureRecognizer {
+  MultiTouchGestureRecognizerCallback onMultiTap;
+  var numberOfTouches = 0;
+
+  MultiTouchGestureRecognizer() {
+    this
+      ..onTapDown = addTouch
+      ..onTapUp = removeTouch
+      ..onTapCancel = cancelTouch
+      ..onTap = captureDefaultTap;
+  }
+
+  void addTouch(int pointer, TapDownDetails details) {
+    numberOfTouches++;
+    onMultiTap(numberOfTouches, true);
+  }
+
+  void removeTouch(int pointer, TapUpDetails details) {
+    numberOfTouches--;
+    onMultiTap(numberOfTouches, false);
+  }
+
+  void cancelTouch(int pointer) {
+    numberOfTouches = 0;
+  }
+
+  void captureDefaultTap(int pointer) {}
+}
+
+typedef MultiTouchGestureRecognizerCallback = void Function(
+    int touchCount, bool addOrRemove);
+
+typedef OnUpdate(DragUpdateDetails details);
+
+class CustomMultiDrag extends Drag {
+  CustomMultiDrag({this.events, this.offset});
+
+  List<PointerDownEvent> events;
+  Offset offset;
+
+  @override
+  void update(DragUpdateDetails details) {
+    var n = events.length;
+    print('$n $details');
+  }
+
+  @override
+  void end(DragEndDetails details) {
+    super.end(details);
+  }
+}
+
+typedef OnDisposeState();
+
+// clone _ImmediatePointerState
+class CustomPointerState extends MultiDragPointerState {
+  final OnDisposeState onDisposeState;
+  CustomPointerState(Offset initialPosition, PointerDeviceKind kind,
+      {this.onDisposeState})
+      : super(initialPosition, kind);
+
+  @override
+  void checkForResolutionAfterMove() {
+    assert(pendingDelta != null);
+    if (pendingDelta.distance > computeHitSlop(kind))
+      resolve(GestureDisposition.accepted);
+  }
+
+  @override
+  void accepted(GestureMultiDragStartCallback starter) {
+    starter(initialPosition);
+  }
+
+  @override
+  void dispose() {
+    onDisposeState.call();
+    super.dispose();
+  }
+}
+
+// clone ImmediateMultiDragGestureRecognizer
+class CustomMultiDragGestureRecognizer
+    extends MultiDragGestureRecognizer<CustomPointerState> {
+  var events = List<PointerDownEvent>();
+
+  /// Create a gesture recognizer for tracking multiple pointers at once.
+  CustomMultiDragGestureRecognizer({
+    Object debugOwner,
+    PointerDeviceKind kind,
+  }) : super(debugOwner: debugOwner, kind: kind);
+
+  @override
+  CustomPointerState createNewPointerState(PointerDownEvent event) {
+    events.add(event);
+    return CustomPointerState(event.position, event.kind, onDisposeState: () {
+      events.remove(event);
+    });
+  }
+
+  @override
+  String get debugDescription => 'custom_multidrag';
+}

flutter_hbb/lib/remote_page.dart

@@ -7,9 +7,10 @@ import 'package:flutter_easyloading/flutter_easyloading.dart';
 import 'dart:async';
 import 'dart:math' as math;
 import 'package:tuple/tuple.dart';
-import 'common.dart';
-import 'model.dart';
 import 'package:wakelock/wakelock.dart';
+import 'common.dart';
+import 'drag.dart';
+import 'model.dart';
 
 class RemotePage extends StatefulWidget {
   RemotePage({Key key, this.id}) : super(key: key);
@@ -26,6 +27,7 @@ class _RemotePageState extends State<RemotePage> {
   bool _showBar = true;
   double _bottom = 0;
   bool _pan = false;
+  var _scaleMode = false;
   final FocusNode _focusNode = FocusNode();
 
   @override
@@ -162,19 +164,35 @@ class _RemotePageState extends State<RemotePage> {
                 )
               : null,
           body: RawGestureDetector(
-              gestures: {
+              gestures: buildGuestures(),
-                MultiTouchGestureRecognizer:
+              child: FlutterEasyLoading(
-                    GestureRecognizerFactoryWithHandlers<
+                child: Container(
-                        MultiTouchGestureRecognizer>(
+                    color: MyTheme.canvasColor,
-                  () => MultiTouchGestureRecognizer(),
+                    child: Stack(children: [
-                  (MultiTouchGestureRecognizer instance) {
+                      ImagePaint(),
-                    instance.onMultiTap = (
+                      CursorPaint(),
-                      touchCount,
+                      SizedBox(
-                      addOrRemove,
+                        width: 0,
-                    ) =>
+                        height: 0,
-                        print('$touchCount, $addOrRemove');
+                        child: _bottom < 100
-                  },
+                            ? Container()
+                            : TextField(
+                                textInputAction: TextInputAction.newline,
+                                autocorrect: false,
+                                enableSuggestions: false,
+                                focusNode: _focusNode,
+                                maxLines: null,
+                                keyboardType: TextInputType.multiline,
+                                onChanged: (x) => print('$x'),
                               ),
+                      ),
+                    ])),
+              )),
+        ));
+  }
+
+  Map<Type, GestureRecognizerFactory> buildGuestures() {
+    var m = {
       TapGestureRecognizer:
           GestureRecognizerFactoryWithHandlers<TapGestureRecognizer>(
         () => TapGestureRecognizer(),
@@ -184,20 +202,32 @@ class _RemotePageState extends State<RemotePage> {
           };
         },
       ),
-                ImmediateMultiDragGestureRecognizer:
+      MultiTouchGestureRecognizer:
-                    GestureRecognizerFactoryWithHandlers<
+          GestureRecognizerFactoryWithHandlers<MultiTouchGestureRecognizer>(
-                        ImmediateMultiDragGestureRecognizer>(
+        () => MultiTouchGestureRecognizer(),
-                  () => ImmediateMultiDragGestureRecognizer(),
+        (MultiTouchGestureRecognizer instance) {
-                  (ImmediateMultiDragGestureRecognizer instance) {
+          instance.onMultiTap = (
+            touchCount,
+            addOrRemove,
+          ) {
+            if (touchCount == 3 && addOrRemove) {
+              setState(() => _scaleMode = !_scaleMode);
+            }
+          };
+        },
+      ),
+      CustomMultiDragGestureRecognizer: GestureRecognizerFactoryWithHandlers<
+          CustomMultiDragGestureRecognizer>(
+        () => CustomMultiDragGestureRecognizer(),
+        (CustomMultiDragGestureRecognizer instance) {
           instance
-                      ..onStart = (x) {
+            ..onStart = (offset) {
-                        return CustomDrag();
+              return CustomMultiDrag(events: instance.events, offset: offset);
             };
         },
       ),
       LongPressGestureRecognizer:
-                    GestureRecognizerFactoryWithHandlers<
+          GestureRecognizerFactoryWithHandlers<LongPressGestureRecognizer>(
-                        LongPressGestureRecognizer>(
         () => LongPressGestureRecognizer(),
         (LongPressGestureRecognizer instance) {
           var x = 0.0;
@@ -225,21 +255,8 @@ class _RemotePageState extends State<RemotePage> {
             };
         },
       ),
-                PanGestureRecognizer:
+      ScaleGestureRecognizer:
-                    GestureRecognizerFactoryWithHandlers<PanGestureRecognizer>(
+          GestureRecognizerFactoryWithHandlers<ScaleGestureRecognizer>(
-                  () => PanGestureRecognizer(),
-                  (PanGestureRecognizer instance) {
-                    instance
-                      ..onStart = (detail) {
-                        print('pan start');
-                      }
-                      ..onUpdate = (detail) {
-                        print('$detail');
-                      };
-                  },
-                ),
-                ScaleGestureRecognizer: GestureRecognizerFactoryWithHandlers<
-                    ScaleGestureRecognizer>(
         () => ScaleGestureRecognizer(),
         (ScaleGestureRecognizer instance) {
           instance
@@ -252,8 +269,7 @@ class _RemotePageState extends State<RemotePage> {
         },
       ),
       DoubleTapGestureRecognizer:
-                    GestureRecognizerFactoryWithHandlers<
+          GestureRecognizerFactoryWithHandlers<DoubleTapGestureRecognizer>(
-                        DoubleTapGestureRecognizer>(
         () => DoubleTapGestureRecognizer(),
         (DoubleTapGestureRecognizer instance) {
           instance.onDoubleTap = () {
@@ -261,31 +277,13 @@ class _RemotePageState extends State<RemotePage> {
           };
         },
       ),
-              },
+    };
-              child: FlutterEasyLoading(
+    if (_scaleMode) {
-                child: Container(
+      m.remove(CustomMultiDragGestureRecognizer);
-                    color: MyTheme.canvasColor,
+    } else {
-                    child: Stack(children: [
+      m.remove(ScaleGestureRecognizer);
-                      ImagePaint(),
+    }
-                      CursorPaint(),
+    return m;
-                      SizedBox(
-                        width: 0,
-                        height: 0,
-                        child: _bottom < 100
-                            ? Container()
-                            : TextField(
-                                textInputAction: TextInputAction.newline,
-                                autocorrect: false,
-                                enableSuggestions: false,
-                                focusNode: _focusNode,
-                                maxLines: null,
-                                keyboardType: TextInputType.multiline,
-                                onChanged: (x) => print('$x'),
-                              ),
-                      ),
-                    ])),
-              )),
-        ));
   }
 
   void close() {
@@ -503,52 +501,3 @@ void showActions(BuildContext context) {
       true,
       0);
 }
-
-class MultiTouchGestureRecognizer extends MultiTapGestureRecognizer {
-  MultiTouchGestureRecognizerCallback onMultiTap;
-  var numberOfTouches = 0;
-
-  MultiTouchGestureRecognizer() {
-    this
-      ..onTapDown = addTouch
-      ..onTapUp = removeTouch
-      ..onTapCancel = cancelTouch
-      ..onTap = captureDefaultTap;
-  }
-
-  void addTouch(int pointer, TapDownDetails details) {
-    numberOfTouches++;
-    onMultiTap(numberOfTouches, true);
-  }
-
-  void removeTouch(int pointer, TapUpDetails details) {
-    numberOfTouches--;
-    onMultiTap(numberOfTouches, false);
-  }
-
-  void cancelTouch(int pointer) {
-    numberOfTouches--;
-    print('$numberOfTouches x');
-  }
-
-  void captureDefaultTap(int pointer) {
-    print('$pointer');
-  }
-}
-
-typedef MultiTouchGestureRecognizerCallback = void Function(
-    int touchCount, bool addOrRemove);
-
-typedef OnUpdate(DragUpdateDetails details);
-
-class CustomDrag extends Drag {
-  @override
-  void update(DragUpdateDetails details) {
-    print('xx $details');
-  }
-
-  @override
-  void end(DragEndDetails details) {
-    super.end(details);
-  }
-}