HarmonyOSAPP控制超声波小车

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1、超声波小车介绍

①.本项目采用的开发套件为HiSpark Wi-Fi IoT智能小车。

②.项目预览。

视频链接：https://www.bilibili.com/video/BV1pS4y1Y72j/。

代码开源地址：https://gitee.com/yukoyu/harmony-wifi-car。

③.框架图

④.HarmonyOS采用 JAVA方式开发

2、小车端开发

①.新建文件夹。

路径：openharmonyapplicationssamplewifi-iotapp

mkdir wificar

②.编写小车电机驱动。

路径：openharmonyapplicationssamplewifi-iotappwificarrobot_l9110s.c

代码：

#define GPIO0 0
#define GPIO1 1
#define GPIO9 9
#define GPIO10 10
#define GPIOFUNC 0
#define PWM_FREQ_FREQUENCY  (60000)
void gpio_control (unsigned int  gpio, IotGpioValue value) {
  hi_io_set_func(gpio, GPIOFUNC);
  IoTGpioSetDir(gpio, IOT_GPIO_DIR_OUT);
  IoTGpioSetOutputVal(gpio, value);
}
//后退
void car_backward(void) {
  gpio_control(GPIO0, IOT_GPIO_VALUE0);
  gpio_control(GPIO1, IOT_GPIO_VALUE1);
  gpio_control(GPIO9, IOT_GPIO_VALUE0);
  gpio_control(GPIO10, IOT_GPIO_VALUE1);
}
//前进
void car_forward(void) {
  gpio_control(GPIO0, IOT_GPIO_VALUE1);
  gpio_control(GPIO1, IOT_GPIO_VALUE0);
  gpio_control(GPIO9, IOT_GPIO_VALUE1);
  gpio_control(GPIO10, IOT_GPIO_VALUE0);
}
//左转
void car_left(void) {
  gpio_control(GPIO0, IOT_GPIO_VALUE0);
  gpio_control(GPIO1, IOT_GPIO_VALUE0);
  gpio_control(GPIO9, IOT_GPIO_VALUE1);
  gpio_control(GPIO10, IOT_GPIO_VALUE0);
}
//右转
void car_right(void) {
  gpio_control(GPIO0, IOT_GPIO_VALUE1);
  gpio_control(GPIO1, IOT_GPIO_VALUE0);
  gpio_control(GPIO9, IOT_GPIO_VALUE0);
  gpio_control(GPIO10, IOT_GPIO_VALUE0);
}
//停止转动
void car_stop(void) {
  gpio_control(GPIO0, IOT_GPIO_VALUE1);
  gpio_control(GPIO1, IOT_GPIO_VALUE1);
  gpio_control(GPIO9, IOT_GPIO_VALUE1);
  gpio_control(GPIO10, IOT_GPIO_VALUE1);
}

③.编写舵机驱动。

路径：openharmonyapplicationssamplewifi-iotappwificarrobot_sg90.c

代码：

#define GPIO2 2
void set_angle( unsigned int duty) {
  IoTGpioInit(GPIO2);
  IoTGpioSetDir(GPIO2, IOT_GPIO_DIR_OUT);
  IoTGpioSetOutputVal(GPIO2, IOT_GPIO_VALUE1);
  hi_udelay(duty);
  IoTGpioSetOutputVal(GPIO2, IOT_GPIO_VALUE0);
  hi_udelay(20000 - duty);
}
//控制电机转动角度  参数范围 1000<time<2000
void custom(int time)
{
  for (int i = 0; i <10; i++) {
    set_angle(time);
  }
}

④.编写超声波驱动。

路径：openharmonyapplicationssamplewifi-iotappwificarrobot_hcsr04.c

代码：

#define GPIO_8 8
#define GPIO_7 7
#define GPIO_FUNC 0
extern int cmm;
void GetDistance  (float *distance) {
  static unsigned long start_time = 0, time = 0;
  IotGpioValue value = IOT_GPIO_VALUE0;
  unsigned int flag = 0;
  IoTWatchDogDisable();
  hi_io_set_func(GPIO_8, GPIO_FUNC);
  IoTGpioSetDir(GPIO_8, IOT_GPIO_DIR_IN);
  IoTGpioSetDir(GPIO_7, IOT_GPIO_DIR_OUT);
  IoTGpioSetOutputVal(GPIO_7, IOT_GPIO_VALUE1);
  hi_udelay(20);
  IoTGpioSetOutputVal(GPIO_7, IOT_GPIO_VALUE0);
  while (1) {
    IoTGpioGetInputVal(GPIO_8, &value);
    if ( value == IOT_GPIO_VALUE1 && flag == 0) 
     start_time = hi_get_us();
    flag = 1;
  }
  if (value == IOT_GPIO_VALUE0 && flag == 1) {
        time = hi_get_us() - start_time;
        start_time = 0;
        break;
  }
  }
  *distance = time * 0.034 / 2;
  printf("distance is %frn",*distance);
  return ;
}

⑤.编写wifi和socket server。

路径：openharmonyapplicationssamplewifi-iotappwificarwifi_sockets.c

代码：

// 接收、发送的数据
static char request[256] = "";
// 未连接热点=0，已连接热点=1
static int g_connected = 0;
int connfd = -1;
// 输出连接信息字符串
// 打印内容样例--> bssid: 38:47:BC:49:01:FA, rssi: 0, connState: 0, reason: 0, ssid: MyMobile
void PrintLinkedInfo(WifiLinkedInfo* info) {
  if (!info) return;
  static char macAddress[32] = {0};
  unsigned char* mac = info->bssid;
  snprintf(macAddress, sizeof(macAddress), "%02X:%02X:%02X:%02X:%02X:%02X", mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
  printf("bssid: %s, rssi: %d, connState: %d, reason: %d, ssid: %srn", macAddress, info->rssi, info->connState, info->disconnectedReason, info->ssid);
}
// 连接状态改变事件处理
void OnWifiConnectionChanged(int state, WifiLinkedInfo* info) {
  if (!info) return;
  // 输出类似内容：OnWifiConnectionChanged 31, state = 1, info =
  printf("%s %d, state = %d, info = rn", __FUNCTION__, __LINE__, state);
  PrintLinkedInfo(info);
  // 根据连接状态设置g_connected
  if (state == WIFI_STATE_AVALIABLE) {
    g_connected = 1;
  } else {
    g_connected = 0;
  }
}
// 扫描状态改变事件处理
void OnWifiScanStateChanged(int state, int size) {
  printf("%s %d, state = %X, size = %drn", __FUNCTION__, __LINE__, state, size);
}
void DisconnectTcpSocket(int connfd) {
  sleep(1);
  printf("do_disconnect...rn");
  lwip_close(connfd);
  sleep(1); // for debug
}
void CloseTcpSocket(int socketfd) {
  printf("do_cleanup...rn");
  lwip_close(socketfd);
}
static void TcpServerHandler(void) {
  ssize_t retval = 0;
  unsigned short port = 20222;
  // 创建一个通信的Socket，并返回一个Socket文件描述符。第一个参数IpV4，第二个参数SOCK_STREAM类型，第三个指用到的协议
  int sockfd = socket(AF_INET, SOCK_STREAM, 0);
  // 客户端地址和地址长度
  struct sockaddr_in clientAddr = {0};
  socklen_t clientAddrLen = sizeof(clientAddr);
  // 服务端地址
  struct sockaddr_in serverAddr = {0};
  serverAddr.sin_family = AF_INET;
  // htons是将整型变量从主机字节顺序转变成网络字节顺序，就是整数在地址空间存储方式变为高位字节存放在内存的低地址处
  serverAddr.sin_port = htons(port);
  // 监听本机的所有IP地址，INADDR_ANY=0x0
  // 将主机数转换成无符号长整型的网络字节顺序
  serverAddr.sin_addr.s_addr = htonl(INADDR_ANY);
  // 服务端绑定端口
  retval = bind(sockfd, (struct sockaddr *)&serverAddr, sizeof(serverAddr));
  if (retval < 0) {
    printf("bind failed, %ld!rn", retval);
    CloseTcpSocket(sockfd);
    return;
  }
  printf("bind to port %d success!rn", port);
  // 开始监听，backlog指Pending连接队列增长到的最大长度。队列满了，再有新连接请求到达，则客户端ECONNREFUSED错误。如果支持重传，则请求忽略。
  int backlog = 1;
  retval = listen(sockfd, backlog);
  if (retval < 0) {
    printf("listen failed!rn");
    CloseTcpSocket(sockfd);
    return;
  }
  printf("listen with %d backlog success!rn", backlog);
  int outerFlag = 1;
  while (outerFlag) {
    // 接受客户端连接，成功会返回一个表示连接的 socket。clientAddr参数将会携带客户端主机和端口信息；失败返回 -1
    // 从Pending连接队列中获取第一个连接，根据sockfd的socket协议、地址族等内容创建一个新的socket文件描述，并返回。
    // 此后的 收、发 都在 表示连接的 socket 上进行；之后 sockfd 依然可以继续接受其他客户端的连接，
    // UNIX系统上经典的并发模型是“每个连接一个进程”——创建子进程处理连接，父进程继续接受其他客户端的连接
    // 鸿蒙liteos-a内核之上，可以使用UNIX的“每个连接一个进程”的并发模型liteos-m内核之上，可以使用“每个连接一个线程”的并发模型
    connfd = accept(sockfd, (struct sockaddr *)&clientAddr, &clientAddrLen);
    if (connfd < 0) {
    printf("accept failed, %d, %drn", connfd, errno);
    CloseTcpSocket(sockfd);
    //outerFlag = 0;
    }
    printf("accept success, connfd = %d !rn", connfd);
    // inet_ntoa：网络地址转换成“.”点隔的字符串格式。ntohs：16位数由网络字节顺序转换为主机字节顺序。
    printf("client addr info: host = %s, port = %drn", inet_ntoa(clientAddr.sin_addr), ntohs(clientAddr.sin_port));
    int innerFlag = 1;
    // 接收消息，然后发送回去
    while (innerFlag) {
    // 后续 收、发 都在 表示连接的 socket 上进行；
    // 在新的Socket文件描述上接收信息.
    retval = recv(connfd, request, sizeof(request), 0);
    if (retval < 0) {
      printf("recv request failed, %ld!rn", retval);
      innerFlag = 0;
    } else if (retval == 0) {
      // 对方主动断开连接
      printf("client disconnected!rn");
      innerFlag = 0;
    } else {
      //printf("recv request{%s} from client done!rn", request);
      // 发送数据
      printf("cc = %d %d %d rn",request[0],request[1],request[2]);
      if (retval <= 0) {
      printf("send response failed, %ld!rn", retval);
      innerFlag = 0;
      }
      if(retval == 3 &&  request[0] == -86)
      {
        if(request[1] = 0x00){
          retval = send(connfd, "aaok", strlen("aaok"), 0);
        }
        if(request[1] = 0x01)
        {
          switch (request[2])
          {
          case 1: car_forward();break;
          case 2: car_right();break;
          case 3: car_backward();break;
          case 4: car_left();break;
          case 0: car_stop();break;
          }
        }
      }
      //printf("send response{%s} to client done!rn", request);
      // 清空缓冲区
      memset(&request, 0, sizeof(request));
    }
    if(innerFlag == 0)
    {
      DisconnectTcpSocket(connfd);
      //outerFlag = 0;
    }
  }
  CloseTcpSocket(sockfd);
  }
}
void *TcpServerTask(void *arg) {
  (void)arg;
  // 先定义两个Wifi监听器，一个连接改变、一个状态改变
  WifiEvent eventListener = {
  .OnWifiConnectionChanged = OnWifiConnectionChanged,
  .OnWifiScanStateChanged = OnWifiScanStateChanged
  };
  // 等待10个系统Ticks。每个ticks多少个us，计算方式= 1000 * 1000 / osKernelGetTickFreq()
  osDelay(10);
  // 注册监听器
  WifiErrorCode errCode = RegisterWifiEvent(&eventListener);
  printf("RegisterWifiEvent: %drn", errCode);
  // 设置Wifi热点信息
  WifiDeviceConfig apConfig = {};
  strcpy(apConfig.ssid, "PDCN");
  strcpy(apConfig.preSharedKey, "1234567888");
  apConfig.securityType = WIFI_SEC_TYPE_PSK;
  int netId = -1;
  // 启用Wifi
  errCode = EnableWifi();
  printf("EnableWifi: %drn", errCode);
  osDelay(10);
  // 设置Wifi热点配置信息，返回生成的网络Id-netId。
  errCode = AddDeviceConfig(&apConfig, &netId);
  printf("AddDeviceConfig: %drn", errCode);
  // 根据网络Id连接到Wifi热点
  g_connected = 0;
  errCode = ConnectTo(netId);
  printf("ConnectTo(%d): %drn", netId, errCode);
  // 未连接完成，则一直等待。g_connected状态会在事件中设置。
  while (!g_connected) {
  osDelay(10);
  }
  printf("g_connected: %drn", g_connected);
  osDelay(50);
  // 联网业务开始，找到netifname=wlan0的netif。
  struct netif* iface = netifapi_netif_find("wlan0");
  if (iface) {
  // 启动DHCP客户端，获取IP地址
  err_t ret = netifapi_dhcp_start(iface);
  printf("netifapi_dhcp_start: %drn", ret);
  // 等待DHCP服务器反馈给予地址
  osDelay(300);
  // 执行线程安全的网络方法，第二个参数是voidFunc，第三个参数是errFunc。如果没有errFunc，那么就执行voidFunc。
  // netifapi_dhcp_start/netifapi_dhcp_stop等都是调用的netifapi_netif_common方法。
  // dhcp_clients_info_show显示信息
  /*
  server :
    server_id : 192.168.0.1
    mask : 255.255.255.0, 1
    gw : 192.168.0.1
    T0 : 3600
    T1 : 1800
    T2 : 3150
  clients <1> :
    mac_idx mac       addr       state  lease  tries  rto
    0    b4c9b9af69f8   192.168.0.10  10    0    1    2
  */
  ret = netifapi_netif_common(iface, dhcp_clients_info_show, NULL);
  printf("netifapi_netif_common: %drn", ret);
  }
  TcpServerHandler();
  // 联网业务结束，断开DHCP
  err_t ret = netifapi_dhcp_stop(iface);
  printf("netifapi_dhcp_stop: %drn", ret);
  // 断开Wifi热点连接
  Disconnect();
  // 移除Wifi热点的配置
  RemoveDevice(netId);
  // 关闭Wifi
  errCode = DisableWifi();
  printf("DisableWifi: %drn", errCode);
  osDelay(200);
}
void WifiSockets(void)
{
  osThreadAttr_t wifisocket;
  wifisocket.name = "TcpServerTask";
  wifisocket.attr_bits = 0U;
  wifisocket.cb_mem = NULL;
  wifisocket.cb_size = 0U;
  wifisocket.stack_mem = NULL;
  wifisocket.stack_size = 10240;
  wifisocket.priority = 25;
  if (osThreadNew(TcpServerTask, NULL, &wifisocket) == NULL) {
    printf("[Ssd1306TestDemo] Falied to create TcpServerTask!n");
  }
}
APP_FEATURE_INIT(WifiSockets);

⑥.编写主控制代码。

路径：openharmonyapplicationssamplewifi-iotappwificarrobot_control.c

代码：

static char data[128] = "";
extern int connfd;
void *RobotCarTestTask(void* param)
{
  (void)param;
  float cmm = 0.0;
  printf("switchrn");
  int i= 0;
  int flag = 0;
  while (1) {
    custom((i%11)*100 + 1000);
    GetDistance(&cmm);
    sprintf(data,"{"angle": %d,"cm":%f}",i,cmm);
    send(connfd, data, strlen(data), 0);//发送距离到APP
    //printf("rn cos = %d  cm =%frn",i,cmm);
    if(flag == 0)
    {
      i++;
      if(i%10 == 0)
      {
        flag = 1;
      }
    }else{
      i--;
      if(i%11 == 0)
      {
        flag = 0;
      }
    }
    osDelay(25); //延时 250ms
  }
}
void RobotCarDemo(void)
{
  osThreadAttr_t attr;
  attr.name = "RobotCarTestTask";
  attr.attr_bits = 0U;
  attr.cb_mem = NULL;
  attr.cb_size = 0U;
  attr.stack_mem = NULL;
  attr.stack_size = 10240;
  attr.priority = 25;
  if (osThreadNew(RobotCarTestTask, NULL, &attr) == NULL) {
    printf("[Ssd1306TestDemo] Falied to create RobotCarTestTask!n");
  }
}
APP_FEATURE_INIT(RobotCarDemo);

⑦.编写编译描述文件。

路径：openharmonyapplicationssamplewifi-iotappwificarBUILD.gn

代码：

static_library("car_wifi") {
    sources = [
        "robot_l9110s.c",
        "robot_sg90.c",
        "robot_control.c",
        "robot_hcsr04.c",
        "wifi_sockets.c",
    ]
    deps =[
    ]
    include_dirs = [
        "//utils/native/lite/include",
        "//kernel/liteos_m/kal/cmsis",
        "//base/iot_hardware/peripheral/interfaces/kits",
        "//device/hisilicon/hispark_pegasus/hi3861_adapter/hals/communication/wifi_lite/wifiservice",
        "//device/hisilicon/hispark_pegasus/hi3861_adapter/kal",
        "//device/hisilicon/hispark_pegasus/sdk_liteos/third_party/lwip_sack/include",
        "//foundation/communication/wifi_lite/interfaces/wifiservice"
    ]
}

⑧.加入编译。

路径：openharmonyapplicationssamplewifi-iotappBUILD.gn

代码：

import("//build/lite/config/component/lite_component.gni")
lite_component("app") {
    features = [
        "wificar:car_wifi"
    ]
}

⑨.编译。

（1）设置编译路径。

hb set
.(英文字符)

（2）选择wifiiot_hispark_pegasus。

（3）执行编译。

hb build -f

（4）输出路径

openharmonyouthispark_pegasuswifiiot_hispark_pegasus

⑩.烧录。

参考烧录：https://ost.51cto.com/posts/11118。

4、HarmonyOS 端开发

①.新建项目

打开 DevEco Studio 3.0.0.800。

选择File -> New ->New Project。

选择。

选择。

点击Finish。

②.应用签名。

（1）复制bundleName。

（2）打开链接。

https://developer.huawei.com/consumer/cn/service/josp/agc/index.html#/myProject。

（3）点击添加项目。

（4）输入项目名。

（5）点击添加应用。

（6）如图设置。

（7）点击。

（8）登录。

（9）获取签名(未连接手机)。

（10）获取签名(连接手机)，点击Try Again，获取成功。

③.导入gson包

implementation 'com.google.code.gson:gson:2.8.9'

④.打开网络权限

"reqPermissions": [
  {"name":"ohos.permission.GET_NETWORK_INFO"},
  {"name":"ohos.permission.SET_NETWORK_INFO"},
  {"name":"ohos.permission.INTERNET"}
],

⑤.UI设置

这里对UI就不展开讲了

⑥.编写代码

编写文件：Elements.java

代码：

package com.example.wificardemo.slice;
public class Elements {
    int angle = 0;
    float cm = 0;
}

编写文件：MainAbilitySlice.java。

代码：

package com.example.wificardemo.slice;
import com.example.wificardemo.ResourceTable;
import ohos.aafwk.ability.AbilitySlice;
import ohos.aafwk.content.Intent;
import ohos.agp.components.Button;
import ohos.agp.components.Component;
import ohos.agp.components.ProgressBar;
import ohos.agp.components.TextField;
import ohos.global.resource.Resource;
import ohos.hiviewdfx.HiLog;
import ohos.hiviewdfx.HiLogLabel;
import java.util.List;
public class MainAbilitySlice extends AbilitySlice {
    private static final HiLogLabel hilog = new HiLogLabel(HiLog.DEBUG ,0x0000, "test0002");
    SocketTest ST = null;
    ProgressBar[] PB = new ProgressBar[11];
    @Override
    public void onStart(Intent intent) {
        int pbs[] = {ResourceTable.Id_progressbar,ResourceTable.Id_progressbar1,ResourceTable.Id_progressbar2,ResourceTable.Id_progressbar3,ResourceTable.Id_progressbar4,ResourceTable.Id_progressbar5,ResourceTable.Id_progressbar6,ResourceTable.Id_progressbar7,ResourceTable.Id_progressbar8,ResourceTable.Id_progressbar9,ResourceTable.Id_progressbar10};
        super.onStart(intent);
        super.setUIContent(ResourceTable.Layout_ability_main);
        Button connects = findComponentById(ResourceTable.Id_connect_car);
        Button bt1 = findComponentById(ResourceTable.Id_button1);
        Button bt2 = findComponentById(ResourceTable.Id_button2);
        Button bt3 = findComponentById(ResourceTable.Id_button3);
        Button bt4 = findComponentById(ResourceTable.Id_button4);
        Button bt5 = findComponentById(ResourceTable.Id_button5);   
        TextField text_field = findComponentById(ResourceTable.Id_text_field);    
        for(int i = 0;i<11;i++)
        {
            PB[i] = (ProgressBar)findComponentById(pbs[i]);
        }
        bt1.setClickedListener(new Component.ClickedListener() {
            @Override
            public void onClick(Component component) {
                ST.sockerSend(1,1);
            }
        });    
        bt2.setClickedListener(new Component.ClickedListener() {
            @Override
            public void onClick(Component component) {
                ST.sockerSend(1,4);
            }
        });
        bt3.setClickedListener(new Component.ClickedListener() {
            @Override
            public void onClick(Component component) {
                ST.sockerSend(1,0);
            }
        });  
        bt4.setClickedListener(new Component.ClickedListener() {
            @Override
            public void onClick(Component component) {
                ST.sockerSend(1,2);
            }
        })   
        bt5.setClickedListener(new Component.ClickedListener() {
            @Override
            public void onClick(Component component) {
                ST.sockerSend(1,3);
            }
        });   
        connects.setClickedListener(new Component.ClickedListener() {
            @Override
            public void onClick(Component component) {
                if(ST !=null)
                {
                    ST = null; //释放
                }
                try {
                    ST = new SocketTest(MainAbilitySlice.this,text_field.getText().toString(),20222);
                    ST.start();
                    Thread.sleep(200);
                    //ST.sockerSend(5,0,0);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }   
    //Socker 接收回调函数
    public void socketCallback(Elements con) {
    
        getUITaskDispatcher().asyncDispatch(new Runnable() {
            @Override
            public void run() {
                PB[con.angle].setProgressValue(con.cm>100 ? 100:(int)con.cm);
            }
        });    
    }  
    @Override
    public void onActive() {
        super.onActive();
    }   
    @Override
    public void onForeground(Intent intent) {
        super.onForeground(intent);
    }
}

编写文件：SocketTest.java。

代码：

package com.example.wificardemo.slice;
import com.google.gson.Gson;
import ohos.hiviewdfx.HiLog;
import ohos.hiviewdfx.HiLogLabel;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
public class SocketTest extends Thread{
    private static final HiLogLabel hilog = new HiLogLabel(HiLog.DEBUG ,0x0000, "test0002");
    Socket socket = null;
    String host ="";
    int port = 0;
    InputStream inputStream = null;
    OutputStream outputStream=null;
    public boolean flag;
    MainAbilitySlice mains = null;   
    public SocketTest(MainAbilitySlice mains,String host,int port) {
        this.mains = mains;
        this.host = host;
        this.port = port;
    }    
    public void sockerSend(int a,int b){
        if(socket != null && outputStream != null)
        {
            new Thread(new Runnable() {
                @Override
                public void run() {
                    try {
                        byte[] data =  new byte[3];
                        data[0] = (byte) 0xaa;
                        data[1] = (byte) a;
                        data[2] = (byte) b;
                        //data[3] = (byte) c;
                        outputStream.write(data);
                        outputStream.flush();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }    
                }
            }).start();
        }else{
    
        }   
    }    
    @Override
    public void run() {
        try {
            flag = true;
            while (flag)
            {
                socket = new Socket(host, port);
                outputStream = socket.getOutputStream();
                inputStream =socket.getInputStream();
                init1();
                socket.close();
            }
        } catch (IOException e) {
            System.out.println("net erorr!"+e);
        }
    }    
    public void init1() {   
        try {
            byte[] b = new byte[1024];
            while (flag)
            {
                int n = inputStream.read(b);
                if(n !=-1)
                {
                    byte[] data = new byte[n];
                    for (int i=0;i<n;i++)
                    {
                        data[i] = b[i];
                    }
                    String str = new String(data);
                    Gson gson = new Gson();
                    HiLog.debug(hilog,"net !"+str,"");
                    if(n > 10) {
                        mains.socketCallback(gson.fromJson(str, Elements.class));
                    }
                }else break;
            }
        }catch (Exception e){
            HiLog.debug(hilog,"net erorr!"+e,"");
        }
    }
}

⑦.点击RUN 安装到手机。

5、测试

视频链接：https://www.bilibili.com/video/BV1pS4y1Y72j/。

代码开源地址：https://gitee.com/yukoyu/harmony-wifi-car。

测试成功!。

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