fix: android, touch mode, move cursor (#8419)

Signed-off-by: fufesou <linlong1266@gmail.com>

flutter/lib/common/widgets/remote_input.dart

@@ -95,7 +95,7 @@ class _RawTouchGestureDetectorRegionState
     }
     if (handleTouch) {
       // Desktop or mobile "Touch mode"
-      if (ffi.cursorModel.move(d.localPosition.dx, d.localPosition.dy)) {
+      if (ffi.cursorModel.moveTapDown(d.localPosition.dx, d.localPosition.dy)) {
         inputModel.tapDown(MouseButtons.left);
       }
     }
@@ -106,7 +106,7 @@ class _RawTouchGestureDetectorRegionState
       return;
     }
     if (handleTouch) {
-      if (ffi.cursorModel.move(d.localPosition.dx, d.localPosition.dy)) {
+      if (ffi.cursorModel.moveTapUp(d.localPosition.dx, d.localPosition.dy)) {
         inputModel.tapUp(MouseButtons.left);
       }
     }

flutter/lib/mobile/pages/remote_page.dart

@@ -717,8 +717,8 @@ class _KeyHelpToolsState extends State<KeyHelpTools> {
     if (renderObject is RenderBox) {
       final size = renderObject.size;
       Offset pos = renderObject.localToGlobal(Offset.zero);
-      gFFI.cursorModel.keyHelpToolsRect =
+      gFFI.cursorModel.keyHelpToolsVisibilityChanged(
-          Rect.fromLTWH(pos.dx, pos.dy, size.width, size.height);
+          Rect.fromLTWH(pos.dx, pos.dy, size.width, size.height));
     }
   }
 
@@ -730,7 +730,7 @@ class _KeyHelpToolsState extends State<KeyHelpTools> {
         inputModel.command;
 
     if (!_pin && !hasModifierOn && !widget.requestShow) {
-      gFFI.cursorModel.keyHelpToolsRect = null;
+      gFFI.cursorModel.keyHelpToolsVisibilityChanged(null);
       return Offstage();
     }
     final size = MediaQuery.of(context).size;
@@ -867,7 +867,7 @@ class ImagePaint extends StatelessWidget {
   Widget build(BuildContext context) {
     final m = Provider.of<ImageModel>(context);
     final c = Provider.of<CanvasModel>(context);
-    final adjust = gFFI.cursorModel.adjustForKeyboard();
+    final adjust = gFFI.cursorModel.adjustForKeyboard;
     var s = c.scale;
     return CustomPaint(
       painter: ImagePainter(
@@ -881,7 +881,7 @@ class CursorPaint extends StatelessWidget {
   Widget build(BuildContext context) {
     final m = Provider.of<CursorModel>(context);
     final c = Provider.of<CanvasModel>(context);
-    final adjust = gFFI.cursorModel.adjustForKeyboard();
+    final adjust = gFFI.cursorModel.adjustForKeyboard;
     var s = c.scale;
     double hotx = m.hotx;
     double hoty = m.hoty;

flutter/lib/models/model.dart

@@ -1807,21 +1807,30 @@ class CursorModel with ChangeNotifier {
   // But we're now using a Container(child: Stack(...)) to wrap the KeyHelpTools,
   // and the listener is on the Container.
   Rect? _keyHelpToolsRect;
+  // `lastIsBlocked` is only used in common/widgets/remote_input.dart -> _RawTouchGestureDetectorRegionState -> onDoubleTap()
+  // Because onDoubleTap() doesn't have the `event` parameter, we can't get the touch event's position.
   bool _lastIsBlocked = false;
+  // This is the flag for the touch mode.
+  // See `moveTapDown` and `moveTapUp` for more details.
+  bool _inTapDown = false;
+  // This is current adjust value for the touch mode.
+  double _adjustForKeyboard = 0.0;
+  // This is the last two adjust value for the touch mode.
+  // This value is used to avoid the cursor jumping in one tapDown and tapUp event.
+  double _adjustForKeyboard2 = 0.0;
 
-  set keyHelpToolsRect(Rect? r) {
+  keyHelpToolsVisibilityChanged(Rect? r) {
     _keyHelpToolsRect = r;
     if (r == null) {
       _lastIsBlocked = false;
     } else {
-      // `lastIsBlocked` is only used in common/widgets/remote_input.dart -> _RawTouchGestureDetectorRegionState -> onDoubleTap()
-      // Because onDoubleTap() doesn't have the `event` parameter, we can't get the touch event's position.
-      //
       // Block the touch event is safe here.
       // `lastIsBlocked` is only used in onDoubleTap() to block the touch event from the KeyHelpTools.
       // `lastIsBlocked` will be set when the cursor is moving or touch somewhere else.
       _lastIsBlocked = true;
     }
+    _adjustForKeyboard = 0.0;
+    _adjustForKeyboard2 = 0.0;
   }
 
   get lastIsBlocked => _lastIsBlocked;
@@ -1871,15 +1880,18 @@ class CursorModel with ChangeNotifier {
   }
 
   get keyboardHeight => MediaQueryData.fromWindow(ui.window).viewInsets.bottom;
+  get scale => parent.target?.canvasModel.scale ?? 1.0;
 
-  double adjustForKeyboard() {
+  get adjustForKeyboard => _adjustForKeyboard;
+  _updateAdjustForKeyboard() {
     final m = MediaQueryData.fromWindow(ui.window);
     final size = m.size;
     if (keyboardHeight < 100) return 0;
-    final s = parent.target?.canvasModel.scale ?? 1.0;
     final thresh = (size.height - keyboardHeight) / 2;
-    var h = (_y - getVisibleRect().top) * s; // local physical display height
+    final h =
-    return h - thresh;
+        (_y - getVisibleRect().top) * scale; // local physical display height
+    _adjustForKeyboard2 = _adjustForKeyboard;
+    _adjustForKeyboard = h - thresh;
   }
 
   // mobile Soft keyboard, block touch event from the KeyHelpTools
@@ -1896,23 +1908,64 @@ class CursorModel with ChangeNotifier {
     return false;
   }
 
+  // mobile touch mode
+  // We do not update adjustForKeyboard here.
+  // Because `moveTapUp` will also trigger `moveLocal` to update the cursor position.
+  // And `moveLocal` depends on `adjustForKeyboard`.
+  // If we update `adjustForKeyboard` here, the cursor will move to the wrong position.
+  //
+  // We can trigger the update in `moveTapUp` and use `_inTapDown` to control the update.
+  // If `_inTapDown` is timeout, we suppose the touch event is a long press event, and do not update `adjustForKeyboard`.
+  moveTapDown(double x, double y) {
+    if (shouldBlock(x, y)) {
+      _lastIsBlocked = true;
+      return false;
+    }
+    _lastIsBlocked = false;
+    moveLocal(x, y, adjust: _adjustForKeyboard);
+    parent.target?.inputModel.moveMouse(_x, _y);
+    _inTapDown = true;
+    Future.delayed(Duration(milliseconds: 500), () {
+      _inTapDown = false;
+    });
+    return true;
+  }
+
+  // mobile touch mode
+  moveTapUp(double x, double y) {
+    if (shouldBlock(x, y)) {
+      _lastIsBlocked = true;
+      return false;
+    }
+    _lastIsBlocked = false;
+
+    final wasInTapDown = _inTapDown;
+    if (_inTapDown) {
+      _updateAdjustForKeyboard();
+      _inTapDown = false;
+    }
+    parent.target?.inputModel.moveMouse(_x, _y);
+    moveLocal(x, y,
+        adjust: wasInTapDown ? _adjustForKeyboard2 : _adjustForKeyboard);
+    return true;
+  }
+
   move(double x, double y) {
     if (shouldBlock(x, y)) {
       _lastIsBlocked = true;
       return false;
     }
     _lastIsBlocked = false;
-    moveLocal(x, y);
     parent.target?.inputModel.moveMouse(_x, _y);
+    moveLocal(x, y, adjust: _adjustForKeyboard);
     return true;
   }
 
-  moveLocal(double x, double y) {
+  moveLocal(double x, double y, {double adjust = 0}) {
-    final scale = parent.target?.canvasModel.scale ?? 1.0;
     final xoffset = parent.target?.canvasModel.x ?? 0;
     final yoffset = parent.target?.canvasModel.y ?? 0;
     _x = (x - xoffset) / scale + _displayOriginX;
-    _y = (y - yoffset) / scale + _displayOriginY;
+    _y = (y - yoffset + adjust) / scale + _displayOriginY;
     notifyListeners();
   }