HarmonyOSAPP控制超声波小车

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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

①.新建文件夹。

路径：openharmony\applications\sample\wifi-iot\app\

mkdir wificar

②.编写小车电机驱动。

路径：openharmony\applications\sample\wifi-iot\app\wificar\robot_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：openharmony\applications\sample\wifi-iot\app\wificar\robot_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：openharmony\applications\sample\wifi-iot\app\wificar\robot_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 %f\r\n",*distance);
 return ;
}

⑤.编写wifi和socket server。

路径：openharmony\applications\sample\wifi-iot\app\wificar\wifi_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 \r\n",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：openharmony\applications\sample\wifi-iot\app\wificar\robot_control.c

代码：

static char data[128] = "";
extern int connfd;
void *RobotCarTestTask(void* param)
{
 (void)param;
 float cmm = 0.0;
 printf("switch\r\n");
 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("\r\n cos = %d cm =%f\r\n",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：openharmony\applications\sample\wifi-iot\app\wificar\BUILD.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：openharmony\applications\sample\wifi-iot\app\BUILD.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

openharmony\out\hispark_pegasus\wifiiot_hispark_pegasus

⑩.烧录。

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

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。

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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