安卓纯native层模拟手指触摸

前言: 写此项目主要是因为市面上好像并没有一个像样的模拟触摸工具(不与手指触摸冲突.有人维护并且开源)

其实这个项目去年就写完了，但是还是突然想记录一下…

思路

本来想的很简单,用uinput模块创建驱动并提交事件，但是写完了才发现并没有这么简单,一但手指触摸和虚拟触摸同时存在就会冲突

然后又想着可否把真实的触摸给屏蔽掉,与虚拟触摸进行融合,然后在虚拟设备中统一提交?

说干就淦！

实现

初始化屏幕信息

void touch::InitScreenInfo()
{
    std::string window_size = exec("wm size");
    sscanf(window_size.c_str(), "Physical size: %dx%d", &this->screenInfo.width, &this->screenInfo.height);
}//初始化屏幕分辨率,方向单独放在一个线程了

初始化触摸屏信息

void touch::InitTouchScreenInfo()
{
    bool isFound{false};//是否已经找到了一个疑似触摸屏的设备
    for (const auto &entry: std::filesystem::directory_iterator("/dev/input/"))
    {
        int fd = open(entry.path().c_str(), O_RDWR);
        if(fd < 0)
        {
            std::cout<<"打开"<<entry.path()<<"失败"<<std::endl;
        }
        input_absinfo absinfo{};
        ioctl(fd, EVIOCGABS(ABS_MT_SLOT), &absinfo);
        if (absinfo.maximum == 9)
        {
            if(!isFound)
            {
                isFound = true;
                this->touchScreenInfo.fd = open(entry.path().c_str(), O_RDWR);
                close(fd);
                if(touchScreenInfo.width == 0||touchScreenInfo.height == 0)
                {
                    input_absinfo absX{}, absY{};
                    ioctl(touchScreenInfo.fd, EVIOCGABS(ABS_MT_POSITION_X), &absX);
                    ioctl(touchScreenInfo.fd, EVIOCGABS(ABS_MT_POSITION_Y), &absY);
                    if(absX.maximum!=0&&absY.maximum!=0)
                    {
                        this->touchScreenInfo.width = absX.maximum;
                        this->touchScreenInfo.height = absY.maximum;
                    }
                }
            }
            else
            {
                if(touchScreenInfo.width == 0||touchScreenInfo.height == 0)
                {
                    input_absinfo absX{}, absY{};
                    ioctl(fd, EVIOCGABS(ABS_MT_POSITION_X), &absX);
                    ioctl(fd, EVIOCGABS(ABS_MT_POSITION_Y), &absY);
                    if(absX.maximum!=0 && absY.maximum!=0)
                    {
                        this->touchScreenInfo.width = absX.maximum;
                        this->touchScreenInfo.height = absY.maximum;
                    }
                }
                ioctl(fd, EVIOCGRAB, 0x1);//独占输入,只有此进程才能接收到事件 -_-
                threads.emplace_back(&touch::PTScreenEventToFingerByFd,this,fd);
            }
        }
    }//遍历/dev/input/下所有eventX，如果ABS_MT_SLOT为9(即最大支持10点触控)就视为物理触摸屏
}

这样写是因为ABS_MT_SLOT为9的设备在部分设备上好像不止一个……

转换

把物理触摸信息转换为touchOBJ

void touch::PTScreenEventToFinger()
{
    input_event ie{};
    int latestSlot{};
    while (true)
    {
        read(touchScreenInfo.fd, &ie, sizeof(ie));
        {
            if (ie.type == EV_ABS)
            {
                if (ie.code == ABS_MT_SLOT)
                {
                    latestSlot = ie.value;
                    Fingers[0][latestSlot].TRACKING_ID = 114514 + latestSlot;
                    continue;
                }
                if (ie.code == ABS_MT_TRACKING_ID)
                {
                    if (ie.value == -1)
                    {
                        Fingers[0][latestSlot].isDown = false;
                        Fingers[0][latestSlot].isUse = false;
                    } else
                    {
                        Fingers[0][latestSlot].isUse = true;
                        Fingers[0][latestSlot].isDown = true;
                    }
                    continue;
                }
                if (ie.code == ABS_MT_POSITION_X)
                {
                    Fingers[0][latestSlot].x = ie.value;
                    continue;
                }
                if (ie.code == ABS_MT_POSITION_Y)
                {
                    Fingers[0][latestSlot].y = ie.value;
                    continue;
                }
            }
            if (ie.type == EV_SYN)
            {
                if (ie.code == SYN_REPORT)
                {
                    upLoad();
                    continue;
                }
                continue;
            }
        }
    }
}

把touchOBJ转为触摸信息并提交

void touch::upLoad()
{
    std::vector<input_event> events{};
    for (auto &fingers: Fingers)
    {
        for (auto &finger: fingers)
        {
            if (finger.isDown)
            {
                input_event down_events[]
                        {
                                {.type = EV_ABS, .code = ABS_MT_TRACKING_ID, .value = finger.TRACKING_ID},
                                {.type = EV_ABS, .code = ABS_MT_POSITION_X, .value = finger.x},
                                {.type = EV_ABS, .code = ABS_MT_POSITION_Y, .value = finger.y},
                                {.type = EV_SYN, .code = SYN_MT_REPORT, .value = 0},
                        };
                int arrCount = sizeof(down_events) / sizeof(down_events[0]);
                events.insert(events.end(), down_events, down_events + arrCount);
            }
        }
    }
    input_event touchEnd{};
    touchEnd.type = EV_SYN;
    touchEnd.code = SYN_MT_REPORT;
    touchEnd.value = 0;
    events.push_back(touchEnd);
    input_event end{};
    end.type = EV_SYN;
    end.code = SYN_REPORT;
    end.value = 0;
    events.push_back(end);
    for (const auto &event: events)
    {
        write(uinputFd, &event, sizeof(event));
    }
    events.clear();
}

BY

有几点可能要说一下

1.最后提交的时候是使用的多点触控a协议，因为b协议我写出来有bug,没找出哪里的原因,发现linux内核同时支持ab，索性就用a了

2.效率略低,有很大优化空间

3.开源地址