Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Handle out-of-order add/remove pointer events #55740

Merged
merged 4 commits into from
Oct 16, 2024
Merged

Handle out-of-order add/remove pointer events #55740

Show file tree
Hide file tree
Changes from 2 commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
3250fe0
Synthesize pointer remove event
hbatagelo Oct 8, 2024
31d6c00
Add test
hbatagelo Oct 8, 2024
ba8c56a
Merge branch 'flutter:main' into fix-multi-window-pointer-event
hbatagelo Oct 15, 2024
3506111
Add test for double remove events, simplify synthesized event creatio…
hbatagelo Oct 15, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
43 changes: 42 additions & 1 deletion lib/ui/window/pointer_data_packet_converter.cc
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -74,7 +74,42 @@ void PointerDataPacketConverter::ConvertPointerData(
break;
}
case PointerData::Change::kAdd: {
FML_DCHECK(states_.find(pointer_data.device) == states_.end());
auto iter = states_.find(pointer_data.device);
if (iter != states_.end()) {
// Synthesizes a remove event if the pointer was not previously
// removed.
PointerState state = iter->second;
PointerData synthesized_data = pointer_data;
synthesized_data.physical_x = state.physical_x;
synthesized_data.physical_y = state.physical_y;
synthesized_data.pan_x = state.pan_x;
synthesized_data.pan_y = state.pan_y;
synthesized_data.scale = state.scale;
synthesized_data.rotation = state.rotation;
synthesized_data.buttons = state.buttons;

if (delegate_.ViewExists(state.view_id)) {
loic-sharma marked this conversation as resolved.
Show resolved Hide resolved
synthesized_data.view_id = state.view_id;

if (state.is_down) {
// Synthesizes cancel event if the pointer is down.
PointerData synthesized_cancel_event = synthesized_data;
synthesized_cancel_event.change = PointerData::Change::kCancel;
synthesized_cancel_event.synthesized = 1;
loic-sharma marked this conversation as resolved.
Show resolved Hide resolved
UpdatePointerIdentifier(synthesized_cancel_event, state, false);

state.is_down = false;
converted_pointers.push_back(synthesized_cancel_event);
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I'm not very familiar with this code. Could you explain why the cancel event is synthesized only if the view exists? That's not immediately obvious to me

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I replicated the behavior of the non-synthesized/original remove event. When a non-synthesized "remove" is handled, a "cancel" is synthesized if the pointer is down, and a "hover" is synthesized if the pointer location has changed. Here, I replicate the synthesized "cancel" event, but not the "hover" event, since the pointer location is unchanged.

My reasoning for synthesizing the "cancel" event only for valid views is that the framework will ignore events for non-existing views.

}
}

PointerData synthesized_remove_event = synthesized_data;
synthesized_remove_event.change = PointerData::Change::kRemove;
synthesized_remove_event.synthesized = 1;

converted_pointers.push_back(synthesized_remove_event);
}

EnsurePointerState(pointer_data);
converted_pointers.push_back(pointer_data);
break;
Expand All @@ -84,6 +119,11 @@ void PointerDataPacketConverter::ConvertPointerData(
auto iter = states_.find(pointer_data.device);
FML_DCHECK(iter != states_.end());
PointerState state = iter->second;
if (state.view_id != pointer_data.view_id) {
// Ignores remove event if the pointer was previously added to a
// different view.
break;
loic-sharma marked this conversation as resolved.
Show resolved Hide resolved
}

if (state.is_down) {
// Synthesizes cancel event if the pointer is down.
Expand Down Expand Up @@ -362,6 +402,7 @@ PointerState PointerDataPacketConverter::EnsurePointerState(
state.physical_y = pointer_data.physical_y;
state.pan_x = 0;
state.pan_y = 0;
state.view_id = pointer_data.view_id;
states_[pointer_data.device] = state;
return state;
}
Expand Down
1 change: 1 addition & 0 deletions lib/ui/window/pointer_data_packet_converter.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -38,6 +38,7 @@ struct PointerState {
double scale;
double rotation;
int64_t buttons;
int64_t view_id;
};

//------------------------------------------------------------------------------
Expand Down
56 changes: 56 additions & 0 deletions lib/ui/window/pointer_data_packet_converter_unittests.cc
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -510,6 +510,62 @@ TEST(PointerDataPacketConverterTest, CanSynthesizeAdd) {
ASSERT_EQ(result[3].buttons, 0);
}

TEST(PointerDataPacketConverterTest, CanSynthesizeRemove) {
TestDelegate delegate;
delegate.AddView(100);
delegate.AddView(200);
PointerDataPacketConverter converter(delegate);
auto packet = std::make_unique<PointerDataPacket>(3);

PointerData data;
CreateSimulatedPointerData(data, PointerData::Change::kAdd, 0, 0.0, 0.0, 0);
data.view_id = 100;
packet->SetPointerData(0, data);
CreateSimulatedPointerData(data, PointerData::Change::kDown, 0, 3.0, 4.0, 1);
data.view_id = 100;
packet->SetPointerData(1, data);
CreateSimulatedPointerData(data, PointerData::Change::kAdd, 0, 0.0, 0.0, 0);
data.view_id = 200;
packet->SetPointerData(2, data);
auto converted_packet = converter.Convert(*packet);

std::vector<PointerData> result;
UnpackPointerPacket(result, std::move(converted_packet));

ASSERT_EQ(result.size(), (size_t)6);
ASSERT_EQ(result[0].synthesized, 0);
ASSERT_EQ(result[0].view_id, 100);

// A hover should be synthesized.
ASSERT_EQ(result[1].change, PointerData::Change::kHover);
ASSERT_EQ(result[1].synthesized, 1);
ASSERT_EQ(result[1].physical_delta_x, 3.0);
ASSERT_EQ(result[1].physical_delta_y, 4.0);
ASSERT_EQ(result[1].buttons, 0);

ASSERT_EQ(result[2].change, PointerData::Change::kDown);
ASSERT_EQ(result[2].pointer_identifier, 1);
ASSERT_EQ(result[2].synthesized, 0);
ASSERT_EQ(result[2].buttons, 1);

// A cancel should be synthesized.
ASSERT_EQ(result[3].change, PointerData::Change::kCancel);
ASSERT_EQ(result[3].pointer_identifier, 1);
ASSERT_EQ(result[3].synthesized, 1);
ASSERT_EQ(result[3].physical_x, 3.0);
ASSERT_EQ(result[3].physical_y, 4.0);
ASSERT_EQ(result[3].buttons, 1);

// A remove should be synthesized.
ASSERT_EQ(result[4].physical_x, 3.0);
ASSERT_EQ(result[4].physical_y, 4.0);
ASSERT_EQ(result[4].synthesized, 1);
ASSERT_EQ(result[4].view_id, 100);

ASSERT_EQ(result[5].synthesized, 0);
ASSERT_EQ(result[5].view_id, 200);
}

TEST(PointerDataPacketConverterTest, CanHandleThreeFingerGesture) {
// Regression test https://github.com/flutter/flutter/issues/20517.
TestDelegate delegate;
Expand Down