定义在 TransactionCallbackInvoker.h 中。

class CallbackHandle : public RefBase {
public:
    CallbackHandle(const sp<IBinder>& transactionListener, const std::vector<CallbackId>& ids,
                   const sp<IBinder>& sc);

    sp<IBinder> listener;
    std::vector<CallbackId> callbackIds;
    wp<IBinder> surfaceControl;

    bool releasePreviousBuffer = false;
    sp<Fence> previousReleaseFence;
    nsecs_t acquireTime = -1;
    nsecs_t latchTime = -1;
    uint32_t transformHint = 0;
    uint32_t currentMaxAcquiredBufferCount = 0;
    std::shared_ptr<FenceTime> gpuCompositionDoneFence{FenceTime::NO_FENCE};
    CompositorTiming compositorTiming;
    nsecs_t refreshStartTime = 0;
    nsecs_t dequeueReadyTime = 0;
    uint64_t frameNumber = 0;
    ReleaseCallbackId previousReleaseCallbackId = ReleaseCallbackId::INVALID_ID;
};

• listener 是 ITransactionCompletedListener。
• 字段 callbackIds 是 CallbackId 向量。
• 上面两个字段和 ListenerCallbacks 字段相同。
• surfaceControl 是 layer_state_t 的字段 surface，即 SurfaceControl 的 mHandle，在 SurfaceFlinger::setClientStateLocked() 中写入的。