Fix non primary buttons not being captured on windows (#188394)
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Closes #166309.
Windows only captured mouse input for primary-button drags. As a result,
drag gestures using middle, secondary, or X buttons received a pointer
remove when leaving the client area.
Capture is now enabled for every supported mouse button and released
only
after the last pressed mouse button is released.
Also tested on my universal flutter input demo:
https://github.com/CodeDoctorDE/flutter-input-demo/tree/e448c2cf42981d9c8b5186a7e43d1b82a0239619.
~~Currently in draft since I cannot have 2 pull requests open at the
same time.~~
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---------
Co-authored-by: Matthew Kosarek <matt.kosarek@canonical.com>
diff --git a/engine/src/flutter/shell/platform/windows/flutter_window.cc b/engine/src/flutter/shell/platform/windows/flutter_window.cc
index 2b778dd..24398ee 100644
--- a/engine/src/flutter/shell/platform/windows/flutter_window.cc
+++ b/engine/src/flutter/shell/platform/windows/flutter_window.cc
@@ -735,14 +735,11 @@
break;
}
- if (message == WM_LBUTTONDOWN) {
- // Capture the pointer in case the user drags outside the client area.
- // In this case, the "mouse leave" event is delayed until the user
- // releases the button. It's only activated on left click given that
- // it's more common for apps to handle dragging with only the left
- // button.
- SetCapture(window_handle_);
- }
+ // Capture the pointer in case the user drags outside the client area.
+ // In this case, the "mouse leave" event is delayed until the user
+ // releases the button.
+ SetCapture(window_handle_);
+
button_pressed = message;
if (message == WM_XBUTTONDOWN) {
button_pressed = GET_XBUTTON_WPARAM(wparam);
@@ -764,9 +761,6 @@
break;
}
- if (message == WM_LBUTTONUP) {
- ReleaseCapture();
- }
button_pressed = message;
if (message == WM_XBUTTONUP) {
button_pressed = GET_XBUTTON_WPARAM(wparam);
@@ -775,6 +769,17 @@
y_pos = GET_Y_LPARAM(lparam);
flutter_button = ConvertWinButtonToFlutterButton(button_pressed);
+ // WM_*BUTTONUP messages use wparam to report which buttons remain
+ // pressed after this event; release capture only after the last mouse
+ // button is released. WM_*BUTTONDOWN messages already identify the newly
+ // pressed button via the message itself.
+ // See:
+ // https://learn.microsoft.com/en-us/windows/win32/inputdev/wm-lbuttonup
+ if ((wparam & (MK_LBUTTON | MK_RBUTTON | MK_MBUTTON | MK_XBUTTON1 |
+ MK_XBUTTON2)) == 0) {
+ ReleaseCapture();
+ }
+
OnPointerUp(static_cast<double>(x_pos), static_cast<double>(y_pos),
device_kind, kDefaultPointerDeviceId, flutter_button);
break;
diff --git a/engine/src/flutter/shell/platform/windows/flutter_window_unittests.cc b/engine/src/flutter/shell/platform/windows/flutter_window_unittests.cc
index e1fbcfe..3c3a3f0 100644
--- a/engine/src/flutter/shell/platform/windows/flutter_window_unittests.cc
+++ b/engine/src/flutter/shell/platform/windows/flutter_window_unittests.cc
@@ -853,6 +853,80 @@
50);
}
+TEST_F(FlutterWindowTest, NonPrimaryMouseButtonCapturesPointer) {
+ MockFlutterWindow win32window(100, 100);
+ MockWindowBindingHandlerDelegate delegate;
+ EXPECT_CALL(win32window, OnWindowStateEvent).Times(AnyNumber());
+ EXPECT_CALL(delegate, OnWindowStateEvent).Times(AnyNumber());
+ win32window.SetView(&delegate);
+
+ HWND window_handle = win32window.FlutterWindow::GetWindowHandle();
+ ASSERT_NE(window_handle, nullptr);
+ ReleaseCapture();
+ ASSERT_EQ(GetCapture(), nullptr);
+
+ EXPECT_CALL(delegate,
+ OnPointerDown(10.0, 10.0, kFlutterPointerDeviceKindMouse,
+ kDefaultPointerDeviceId,
+ kFlutterPointerButtonMouseSecondary, 0, 0))
+ .Times(1);
+ win32window.InjectWindowMessage(WM_RBUTTONDOWN, MK_RBUTTON,
+ MAKELPARAM(10, 10));
+ EXPECT_EQ(GetCapture(), window_handle);
+
+ EXPECT_CALL(delegate, OnPointerUp(10.0, 10.0, kFlutterPointerDeviceKindMouse,
+ kDefaultPointerDeviceId,
+ kFlutterPointerButtonMouseSecondary))
+ .Times(1);
+ win32window.InjectWindowMessage(WM_RBUTTONUP, 0, MAKELPARAM(10, 10));
+ EXPECT_EQ(GetCapture(), nullptr);
+}
+
+TEST_F(FlutterWindowTest, MouseButtonCaptureReleasedAfterAllButtonsReleased) {
+ MockFlutterWindow win32window(100, 100);
+ MockWindowBindingHandlerDelegate delegate;
+ EXPECT_CALL(win32window, OnWindowStateEvent).Times(AnyNumber());
+ EXPECT_CALL(delegate, OnWindowStateEvent).Times(AnyNumber());
+ win32window.SetView(&delegate);
+
+ HWND window_handle = win32window.FlutterWindow::GetWindowHandle();
+ ASSERT_NE(window_handle, nullptr);
+ ReleaseCapture();
+ ASSERT_EQ(GetCapture(), nullptr);
+
+ EXPECT_CALL(delegate,
+ OnPointerDown(10.0, 10.0, kFlutterPointerDeviceKindMouse,
+ kDefaultPointerDeviceId,
+ kFlutterPointerButtonMouseSecondary, 0, 0))
+ .Times(1);
+ win32window.InjectWindowMessage(WM_RBUTTONDOWN, MK_RBUTTON,
+ MAKELPARAM(10, 10));
+ EXPECT_EQ(GetCapture(), window_handle);
+
+ EXPECT_CALL(delegate,
+ OnPointerDown(10.0, 10.0, kFlutterPointerDeviceKindMouse,
+ kDefaultPointerDeviceId,
+ kFlutterPointerButtonMousePrimary, 0, 0))
+ .Times(1);
+ win32window.InjectWindowMessage(WM_LBUTTONDOWN, MK_LBUTTON | MK_RBUTTON,
+ MAKELPARAM(10, 10));
+ EXPECT_EQ(GetCapture(), window_handle);
+
+ EXPECT_CALL(delegate, OnPointerUp(10.0, 10.0, kFlutterPointerDeviceKindMouse,
+ kDefaultPointerDeviceId,
+ kFlutterPointerButtonMouseSecondary))
+ .Times(1);
+ win32window.InjectWindowMessage(WM_RBUTTONUP, MK_LBUTTON, MAKELPARAM(10, 10));
+ EXPECT_EQ(GetCapture(), window_handle);
+
+ EXPECT_CALL(delegate, OnPointerUp(10.0, 10.0, kFlutterPointerDeviceKindMouse,
+ kDefaultPointerDeviceId,
+ kFlutterPointerButtonMousePrimary))
+ .Times(1);
+ win32window.InjectWindowMessage(WM_LBUTTONUP, 0, MAKELPARAM(10, 10));
+ EXPECT_EQ(GetCapture(), nullptr);
+}
+
TEST_F(FlutterWindowTest, OnTouchPointerDown) {
auto mock_proc_table = std::make_shared<MockWindowsProcTable>();
