flutter::testing::ShellTestVsyncWaiter Class Reference

#include <vsync_waiters_test.h>

Inheritance diagram for flutter::testing::ShellTestVsyncWaiter:

Public Member Functions
	ShellTestVsyncWaiter (const TaskRunners &task_runners, std::shared_ptr< ShellTestVsyncClock > clock)
Public Member Functions inherited from flutter::VsyncWaiter
virtual	~VsyncWaiter ()
void	AsyncWaitForVsync (const Callback &callback)
void	ScheduleSecondaryCallback (uintptr_t id, const fml::closure &callback)

Protected Member Functions
void	AwaitVSync () override
Protected Member Functions inherited from flutter::VsyncWaiter
	VsyncWaiter (const TaskRunners &task_runners)
virtual void	AwaitVSyncForSecondaryCallback ()
void	FireCallback (fml::TimePoint frame_start_time, fml::TimePoint frame_target_time, bool pause_secondary_tasks=true)

Additional Inherited Members
Public Types inherited from flutter::VsyncWaiter
using	Callback = std::function< void(std::unique_ptr< FrameTimingsRecorder >)>
Protected Attributes inherited from flutter::VsyncWaiter
const TaskRunners	task_runners_

Detailed Description

Definition at line 33 of file vsync_waiters_test.h.

Constructor & Destructor Documentation

ShellTestVsyncWaiter()

flutter::testing::ShellTestVsyncWaiter::ShellTestVsyncWaiter ( const TaskRunners &  task_runners, std::shared_ptr< ShellTestVsyncClock >  clock  )

inline

Definition at line 35 of file vsync_waiters_test.h.

      : VsyncWaiter(task_runners), clock_(std::move(clock)) {}

Member Function Documentation

AwaitVSync()

void flutter::testing::ShellTestVsyncWaiter::AwaitVSync ( )

overrideprotectedvirtual

Implements flutter::VsyncWaiter.

Definition at line 35 of file vsync_waiters_test.cc.

                                      {
  FML_DCHECK(task_runners_.GetUITaskRunner()->RunsTasksOnCurrentThread());
  auto vsync_future = clock_->NextVSync();
 
  auto async_wait = std::async([&vsync_future, this]() {
    vsync_future.wait();
 
    // Post the `FireCallback` to the Platform thread so earlier Platform tasks
    // (specifically, the `VSyncFlush` call) will be finished before
    // `FireCallback` is executed. This is only needed for our unit tests.
    //
    // Without this, the repeated VSYNC signals in `VSyncFlush` may start both
    // the current frame in the UI thread and the next frame in the secondary
    // callback (both of them are waiting for VSYNCs). That breaks the unit
    // test's assumption that each frame's VSYNC must be issued by different
    // `VSyncFlush` call (which resets the `will_draw_new_frame` bit).
    //
    // For example, HandlesActualIphoneXsInputEvents will fail without this.
    task_runners_.GetPlatformTaskRunner()->PostTask([this]() {
      FireCallback(fml::TimePoint::Now(), fml::TimePoint::Now());
    });
  });
}

References flutter::VsyncWaiter::FireCallback(), FML_DCHECK, flutter::TaskRunners::GetPlatformTaskRunner(), flutter::TaskRunners::GetUITaskRunner(), fml::TimePoint::Now(), fml::TaskRunner::RunsTasksOnCurrentThread(), and flutter::VsyncWaiter::task_runners_.

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The documentation for this class was generated from the following files:

• shell/common/vsync_waiters_test.h
• shell/common/vsync_waiters_test.cc