本文在前一篇基础上，详细介绍以CrossApp跨平台框架为基础，利用mosquito库和easySQLite库设计实现了基于MQTT协议的android版步进电机控制客户端。

一、开发环境的准备

编译环境为CrossApp平台提供的一键部署windows下android开发环境的工具包：
下载地址：
http://pan.baidu.com/s/1qW6ql32#dir/path=%2FCrossApp-Ide

工具包的安装在此省略。参考文章：
https://www.oschina.net/question/1271569_160671

一步步按照向导设置好自己的软件环境。我安装的是x64版。

二、工程的构建和基本设置

安装好后，运行C:\CrossApp\eclipse下的eclipse.exe

参考：http://blog.csdn.net/j2066/article/details/47624109

菜单->file->new->other

然后next，选对相应的android工程：

导入成功后看到：

看到前面左下角有个红色的叉，这是因为框架代码没有导入进来。
接着，按照前面的方法导入CrossApp框架代码工程：

然后看到有错误提示：

[2017-10-02 20:09:21 - StepMotorController] Unable to resolve target 'android-20'
[2017-10-02 20:14:47 - libCrossApp] Unable to resolve target 'android-20'
[2017-10-02 20:14:49 - libCrossApp] Unable to resolve target 'android-20'

需要修改libCrossApp的属性。
对着libCrossApp点右键，选Properties（属性）：

在Project Build Target中选Android 4.4.2：

对于StepMotorController项目也一样设置这个地方：

接着，我们需要修改一下StepMotorController项目下的make文件:
双击项目下的jni下的Android.mk文件：

需要修改这个地方：

为去掉注释符号：

$(call import-add-path, $(LOCAL_PATH)/../../../..)
$(call import-add-path, $(LOCAL_PATH)/../../../../CrossApp/the_third_party/)

先编译一下，右击项目，Run As->Android Application：

看到命令行有个错误：

这个错误是本项目的NDK构建环境android-ndk-r9路径设置有问题造成的：
右键点StepMotorController属性（Properties）->c/c++ Build->Environment->NDK ROOT:

双击这一行，把NDK ROOT设置为自己的路径，我们装包默认的是C:\CrossApp\android-ndk-r9d：

点OK：

还有一个地方需要修改：

修改为我们安装的目录：
C:\CrossApp\android-ndk-r9d\ndk-build.cmd

点OK，编译一下，看到一条错误：

jni/../../Classes/easySQLite/SqlCommon.h:136:22: error: format not a string literal and no format arguments [-Werror=format-security]

参考网上文章，原因是：

　　android-ndk-r9与Eclipse的版本不兼容问题

解决方法:

　　在对应项目的proj.android/jni/Application.mk添加一句话

　　APP_CFLAGS += -Wno-error=format-security

　　意思就是无视这个error
　　

再次编译，又出来错误：

jni/../../Classes/MenuViewController.cpp:105:15: error: converting to execution character set: Illegal byte sequence

这个错误原因是MenuViewController.cpp这个文件的文本格式是ANSI，因为不是支持unicode的格式，所以，不支持中文编码。
解决这个问题的方法是，用记事本打开这个文件另存为UTF-8格式：

编译一下，又出现错误：

jni/../../Classes/easySQLite/SqlCommon.cpp: In member function 'sql::string sql::time::format(const char*)':
jni/../../Classes/easySQLite/SqlCommon.cpp:70:38: error: 'localtime_s' was not declared in this scopeif (localtime_s(&localtime, &_value) == 0)^
jni/../../Classes/easySQLite/SqlCommon.cpp: In function 'sql::string sql::intToStr(int)':
jni/../../Classes/easySQLite/SqlCommon.cpp:116:43: error: '_itoa_s' was not declared in this scope_itoa_s(value, buffer, sizeof(buffer), 10);^
jni/../../Classes/easySQLite/SqlCommon.cpp: In function 'sql::string sql::intToStr(sql::integer)':
jni/../../Classes/easySQLite/SqlCommon.cpp:123:45: error: '_i64toa_s' was not declared in this scope_i64toa_s(value, buffer, sizeof(buffer), 10);^
make.exe: *** [obj/local/armeabi/objs/CrossApp_cpp_shared/__/__/Classes/easySQLite/SqlCommon.o] Error 1

这些错误的原因是我们目前使用的easySQLite库版本太老了，g++编译器（ndk用的是4.8）对这些函数不支持，解决方法是下载一个更新一点的版本来替换原库。这个版本是cocos-2dx引擎提供的：
https://github.com/gelldur/easysqlite

下载下来，把easysqlite-master.zip\easysqlite-master\easySQLite中所有原代码替换原库中的对应文件，然后重新编译。
然后出现一堆错误：

jni/../../Classes/MQTT/mosquittopp.cpp:123: error: undefined reference to 'mosquitto_destroy'
jni/../../Classes/MQTT/mosquittopp.cpp:76: error: undefined reference to 'mosquitto_lib_init'
jni/../../Classes/MQTT/mosquittopp.cpp:81: error: undefined reference to 'mosquitto_lib_cleanup'
jni/../../Classes/MQTT/mosquittopp.cpp:86: error: undefined reference to 'mosquitto_strerror'
jni/../../Classes/MQTT/mosquittopp.cpp:91: error: undefined reference to 'mosquitto_connack_string'
jni/../../Classes/MQTT/mosquittopp.cpp:96: error: undefined reference to 'mosquitto_sub_topic_tokenise'
jni/../../Classes/MQTT/mosquittopp.cpp:101: error: undefined reference to 'mosquitto_sub_topic_tokens_free'
jni/../../Classes/MQTT/mosquittopp.cpp:106: error: undefined reference to 'mosquitto_topic_matches_sub'
jni/../../Classes/MQTT/mosquittopp.cpp:111: error: undefined reference to 'mosquitto_new'
jni/../../Classes/MQTT/mosquittopp.cpp:112: error: undefined reference to 'mosquitto_connect_callback_set'
jni/../../Classes/MQTT/mosquittopp.cpp:113: error: undefined reference to 'mosquitto_disconnect_callback_set'
jni/../../Classes/MQTT/mosquittopp.cpp:114: error: undefined reference to 'mosquitto_publish_callback_set'
jni/../../Classes/MQTT/mosquittopp.cpp:115: error: undefined reference to 'mosquitto_message_callback_set'
jni/../../Classes/MQTT/mosquittopp.cpp:116: error: undefined reference to 'mosquitto_subscribe_callback_set'
jni/../../Classes/MQTT/mosquittopp.cpp:117: error: undefined reference to 'mosquitto_unsubscribe_callback_set'
jni/../../Classes/MQTT/mosquittopp.cpp:118: error: undefined reference to 'mosquitto_log_callback_set'
jni/../../Classes/MQTT/mosquittopp.cpp:129: error: undefined reference to 'mosquitto_reinitialise'
jni/../../Classes/MQTT/mosquittopp.cpp:131: error: undefined reference to 'mosquitto_connect_callback_set'
jni/../../Classes/MQTT/mosquittopp.cpp:132: error: undefined reference to 'mosquitto_disconnect_callback_set'
jni/../../Classes/MQTT/mosquittopp.cpp:133: error: undefined reference to 'mosquitto_publish_callback_set'
jni/../../Classes/MQTT/mosquittopp.cpp:134: error: undefined reference to 'mosquitto_message_callback_set'
jni/../../Classes/MQTT/mosquittopp.cpp:135: error: undefined reference to 'mosquitto_subscribe_callback_set'
jni/../../Classes/MQTT/mosquittopp.cpp:136: error: undefined reference to 'mosquitto_unsubscribe_callback_set'
jni/../../Classes/MQTT/mosquittopp.cpp:137: error: undefined reference to 'mosquitto_log_callback_set'
jni/../../Classes/MQTT/mosquittopp.cpp:144: error: undefined reference to 'mosquitto_connect'
jni/../../Classes/MQTT/mosquittopp.cpp:149: error: undefined reference to 'mosquitto_connect_bind'
jni/../../Classes/MQTT/mosquittopp.cpp:154: error: undefined reference to 'mosquitto_connect_async'
jni/../../Classes/MQTT/mosquittopp.cpp:159: error: undefined reference to 'mosquitto_connect_bind_async'
jni/../../Classes/MQTT/mosquittopp.cpp:164: error: undefined reference to 'mosquitto_reconnect'
jni/../../Classes/MQTT/mosquittopp.cpp:169: error: undefined reference to 'mosquitto_reconnect_async'
jni/../../Classes/MQTT/mosquittopp.cpp:174: error: undefined reference to 'mosquitto_disconnect'
jni/../../Classes/MQTT/mosquittopp.cpp:179: error: undefined reference to 'mosquitto_socket'
jni/../../Classes/MQTT/mosquittopp.cpp:184: error: undefined reference to 'mosquitto_will_set'
jni/../../Classes/MQTT/mosquittopp.cpp:189: error: undefined reference to 'mosquitto_will_clear'
jni/../../Classes/MQTT/mosquittopp.cpp:194: error: undefined reference to 'mosquitto_username_pw_set'
jni/../../Classes/MQTT/mosquittopp.cpp:199: error: undefined reference to 'mosquitto_publish'
jni/../../Classes/MQTT/mosquittopp.cpp:204: error: undefined reference to 'mosquitto_reconnect_delay_set'
jni/../../Classes/MQTT/mosquittopp.cpp:209: error: undefined reference to 'mosquitto_max_inflight_messages_set'
jni/../../Classes/MQTT/mosquittopp.cpp:214: error: undefined reference to 'mosquitto_message_retry_set'
jni/../../Classes/MQTT/mosquittopp.cpp:219: error: undefined reference to 'mosquitto_subscribe'
jni/../../Classes/MQTT/mosquittopp.cpp:224: error: undefined reference to 'mosquitto_unsubscribe'
jni/../../Classes/MQTT/mosquittopp.cpp:229: error: undefined reference to 'mosquitto_loop'
jni/../../Classes/MQTT/mosquittopp.cpp:234: error: undefined reference to 'mosquitto_loop_misc'
jni/../../Classes/MQTT/mosquittopp.cpp:239: error: undefined reference to 'mosquitto_loop_read'
jni/../../Classes/MQTT/mosquittopp.cpp:244: error: undefined reference to 'mosquitto_loop_write'
jni/../../Classes/MQTT/mosquittopp.cpp:249: error: undefined reference to 'mosquitto_loop_forever'
jni/../../Classes/MQTT/mosquittopp.cpp:254: error: undefined reference to 'mosquitto_loop_start'
jni/../../Classes/MQTT/mosquittopp.cpp:259: error: undefined reference to 'mosquitto_loop_stop'
jni/../../Classes/MQTT/mosquittopp.cpp:264: error: undefined reference to 'mosquitto_want_write'
jni/../../Classes/MQTT/mosquittopp.cpp:269: error: undefined reference to 'mosquitto_opts_set'
jni/../../Classes/MQTT/mosquittopp.cpp:274: error: undefined reference to 'mosquitto_threaded_set'
jni/../../Classes/MQTT/mosquittopp.cpp:279: error: undefined reference to 'mosquitto_user_data_set'
jni/../../Classes/MQTT/mosquittopp.cpp:294: error: undefined reference to 'mosquitto_tls_set'
jni/../../Classes/MQTT/mosquittopp.cpp:299: error: undefined reference to 'mosquitto_tls_opts_set'
jni/../../Classes/MQTT/mosquittopp.cpp:304: error: undefined reference to 'mosquitto_tls_insecure_set'
jni/../../Classes/MQTT/mosquittopp.cpp:309: error: undefined reference to 'mosquitto_tls_psk_set'
collect2.exe: error: ld returned 1 exit status
make.exe: *** [obj/local/armeabi/libCrossApp_cpp.so] Error 1

这些错误原因，是没有把mosquitto的源代码编译进去，为什么没有编译进去呢？这需要看makefile是怎么写的。看android.mk中有这么 一行：

MY_FILES_SUFFIX := %.cpp

这是指定文件后缀为.cpp，也就是只搜索项目中的cpp文件，而不搜集c文件，在它后面加上%.c以支持编译c文件：

MY_FILES_SUFFIX := %.cpp %.c

再编译可以看到mosquitto源代码已经编译进去了，但看到一堆错误：

C:/CrossApp/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/windows-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.8/../../../../arm-linux-androideabi/bin/ld.exe: error: ./obj/local/armeabi/libCrossApp.a(sqlite3.o): multiple definition of 'sqlite3_compileoption_get'
C:/CrossApp/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/windows-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.8/../../../../arm-linux-androideabi/bin/ld.exe: ./obj/local/armeabi/objs/CrossApp_cpp_shared/__/__/Classes/easySQLite/sqlite3.o: previous definition here......C:/CrossApp/android-ndk-r9d/toolchains/arm-linux-androideabi-4.8/prebuilt/windows-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.8/../../../../arm-linux-androideabi/bin/ld.exe: ./obj/local/armeabi/objs/CrossApp_cpp_shared/__/__/Classes/easySQLite/sqlite3.o: previous definition here
jni/../../Classes/MQTT/mosquitto.c:282: error: undefined reference to 'pthread_cancel'
jni/../../Classes/MQTT/thread_mosq.c:66: error: undefined reference to 'pthread_cancel'
collect2.exe: error: ld returned 1 exit status
make.exe: *** [obj/local/armeabi/libCrossApp_cpp.so] Error 1

这一堆的错误，主要是有两个：
1、sqlite3这个目标文件已经在CrossApp链接过了，所以，这里提示重复定义；
2、mosquitto.c、thread_mosq.c所使用的pthread_cancel这个poxis函数，在android的ndk平台不支持。

对于第一个错误，需要修改android.mk，在编译时，过滤掉sqlite3.c文件。把

LOCAL_SRC_FILES  := $(MY_SRC_LIST)

修改为：

LOCAL_SRC_FILES  := $(filter-out %/sqlite3.c,$(MY_SRC_LIST)) #don't compile sqlite3.c ,becase it has been contained in the CrossApp core lib . #$(MY_SRC_LIST)

意思是从MY_SRC_LIST所包含的文件中过滤掉所有的sqlite3.c文件，当然实际上只有一个。
重新编译链接，可以看到剩下二个错误：

jni/../../Classes/MQTT/mosquitto.c:282: error: undefined reference to 'pthread_cancel'
jni/../../Classes/MQTT/thread_mosq.c:66: error: undefined reference to 'pthread_cancel'
collect2.exe: error: ld returned 1 exit status
make.exe: *** [obj/local/armeabi/libCrossApp_cpp.so] Error 1

需要修改mosquitto.c、thread_mosq.c。

对于这一部分，参考网上的解决方案，使用了pthread_kill来代替pthread_cancel，至于有没有什么不妥，就可能不好说了。目前先这样解决。
nano-CrossApp\projects\StepMotorController\Classes\MQTT\mosquitto.c中的
void _mosquitto_destroy(struct mosquitto *mosq)函数修改部分如下：

红色的部分是需要添加的。

#include "platform/CCPlatformConfig.h"void _mosquitto_destroy(struct mosquitto *mosq)
{struct _mosquitto_packet *packet;if(!mosq) return;#ifdef WITH_THREADINGif(mosq->threaded == mosq_ts_self && !pthread_equal(mosq->thread_id, pthread_self())){
#if (CC_TARGET_PLATFORM == CC_PLATFORM_ANDROID)//if ( (ESRCH= = pthread_kill(mosq->thread_id, SIGUSR1))) //{ //  printf("Error cancelling thread %d, error = %d (%s)", pthread_id, status, strerror status));//} if(pthread_kill(mosq->thread_id, 0)!= ESRCH){//printf("thread %d exists!\n", pid);pthread_kill(mosq->thread_id, SIGQUIT);//printf("after kill\n");}
#else pthread_cancel(mosq->thread_id);#endifpthread_join(mosq->thread_id, NULL);mosq->threaded = mosq_ts_none;}if(mosq->id){/* If mosq->id is not NULL then the client has already been initialised* and so the mutexes need destroying. If mosq->id is NULL, the mutexes* haven't been initialised. */pthread_mutex_destroy(&mosq->callback_mutex);pthread_mutex_destroy(&mosq->log_callback_mutex);pthread_mutex_destroy(&mosq->state_mutex);pthread_mutex_destroy(&mosq->out_packet_mutex);pthread_mutex_destroy(&mosq->current_out_packet_mutex);pthread_mutex_destroy(&mosq->msgtime_mutex);pthread_mutex_destroy(&mosq->in_message_mutex);pthread_mutex_destroy(&mosq->out_message_mutex);pthread_mutex_destroy(&mosq->mid_mutex);}
#endifif(mosq->sock != INVALID_SOCKET){_mosquitto_socket_close(mosq);}_mosquitto_message_cleanup_all(mosq);_mosquitto_will_clear(mosq);
#ifdef WITH_TLSif(mosq->ssl){SSL_free(mosq->ssl);}if(mosq->ssl_ctx){SSL_CTX_free(mosq->ssl_ctx);}if(mosq->tls_cafile) _mosquitto_free(mosq->tls_cafile);if(mosq->tls_capath) _mosquitto_free(mosq->tls_capath);if(mosq->tls_certfile) _mosquitto_free(mosq->tls_certfile);if(mosq->tls_keyfile) _mosquitto_free(mosq->tls_keyfile);if(mosq->tls_pw_callback) mosq->tls_pw_callback = NULL;if(mosq->tls_version) _mosquitto_free(mosq->tls_version);if(mosq->tls_ciphers) _mosquitto_free(mosq->tls_ciphers);if(mosq->tls_psk) _mosquitto_free(mosq->tls_psk);if(mosq->tls_psk_identity) _mosquitto_free(mosq->tls_psk_identity);
#endifif(mosq->address){_mosquitto_free(mosq->address);mosq->address = NULL;}if(mosq->id){_mosquitto_free(mosq->id);mosq->id = NULL;}if(mosq->username){_mosquitto_free(mosq->username);mosq->username = NULL;}if(mosq->password){_mosquitto_free(mosq->password);mosq->password = NULL;}if(mosq->host){_mosquitto_free(mosq->host);mosq->host = NULL;}if(mosq->bind_address){_mosquitto_free(mosq->bind_address);mosq->bind_address = NULL;}/* Out packet cleanup */if(mosq->out_packet && !mosq->current_out_packet){mosq->current_out_packet = mosq->out_packet;mosq->out_packet = mosq->out_packet->next;}while(mosq->current_out_packet){packet = mosq->current_out_packet;/* Free data and reset values */mosq->current_out_packet = mosq->out_packet;if(mosq->out_packet){mosq->out_packet = mosq->out_packet->next;}_mosquitto_packet_cleanup(packet);_mosquitto_free(packet);}_mosquitto_packet_cleanup(&mosq->in_packet);if(mosq->sockpairR != INVALID_SOCKET){COMPAT_CLOSE(mosq->sockpairR);mosq->sockpairR = INVALID_SOCKET;}if(mosq->sockpairW != INVALID_SOCKET){COMPAT_CLOSE(mosq->sockpairW);mosq->sockpairW = INVALID_SOCKET;}
}

第二个、
对于nano-CrossApp\projects\StepMotorController\Classes\MQTT\thread_mosq.c中的
int mosquitto_loop_stop(struct mosquitto *mosq, bool force)函数修改如下：

#include <errno.h>
#include "platform/CCPlatformConfig.h"int mosquitto_loop_stop(struct mosquitto *mosq, bool force)
{
#ifdef WITH_THREADING
#  ifndef WITH_BROKERchar sockpair_data = 0;
#  endifif(!mosq || mosq->threaded != mosq_ts_self) return MOSQ_ERR_INVAL;/* Write a single byte to sockpairW (connected to sockpairR) to break out* of select() if in threaded mode. */if(mosq->sockpairW != INVALID_SOCKET){
#ifndef WIN32if(write(mosq->sockpairW, &sockpair_data, 1)){}
#elsesend(mosq->sockpairW, &sockpair_data, 1, 0);
#endif}if(force){
#if (CC_TARGET_PLATFORM == CC_PLATFORM_ANDROID)//if ( (ESRCH= = pthread_kill(mosq->thread_id, SIGUSR1))) //{ //  printf("Error cancelling thread %d, error = %d (%s)", pthread_id, status, strerror status));//} if(pthread_kill(mosq->thread_id, 0)!= ESRCH){//printf("thread %d exists!\n", pid);pthread_kill(mosq->thread_id, SIGQUIT);//printf("after kill\n");}
#else pthread_cancel(mosq->thread_id);#endif}pthread_join(mosq->thread_id, NULL);mosq->thread_id = pthread_self();mosq->threaded = mosq_ts_none;return MOSQ_ERR_SUCCESS;
#elsereturn MOSQ_ERR_NOT_SUPPORTED;
#endif
}

修改之后，重新编译链接，ok。

三、验证一下android版对MQTT broker的连接功能

然后接上手机（安卓系统，我的版本是4.4.4）：

这里是还没对broker的参数进行设置，需要设置一下server ip，一般情况下，可以使用wifi在同一个局域网下连接服务器了。但是因为我使用的wifi是在台式机接的360随身wifi，因此，没别的办法，只能从外网来连接我台式机了。
所以，需要在路由上做ip映射。

我的路由是水星MAC1200R，进入路由设置界面，点右上角的高级设置，然后点开左边菜单高级用户，点虚拟服务器，看到如下界面：

然后点那个加号添加：

在常用服务器中选SOCK，外部端口和内部端口都填1883，ip地址填要映射到的台式机IP，我的是10.0.0.108，协议类型可以默认，为ALL，填完之后，点最右边保存。
这样就ok了。

下面查看一下公网IP，点右上角常用设置，然后左边菜单点上网设置，可以看到IP地址：

这个IP地址：123.xxx.xxx.xxx就是我们宽带的公网IP，也就是我们需要在手机号上填写的IP地址。这样，当我们连该IP的时候，路由就把该连接映射到我台式机上了。
下面系列图片是在手机上的操作：

可以看到这里出现了bug！

继续：

但保存之后，返回主界面，又出现了bug：连接的时候，没有使用新设置的IP地址。

以上第一个bug是布局格式选得不合适。

关于CrossApp布局格式的参数的意义请参考：
https://www.w3cschool.cn/crossapp/rv2g1pw1.html

对布局的设置在void SettingsViewController::viewDidLoad()函数中，经过测试，用比例的方式来布局，相关参数适合设置（我测试的手机是三星i9100 galaxy s2，主屏分辨率：800x480像素）如下：

void SettingsViewController::viewDidLoad()
{CAImageView* view1 = CAImageView::createWithImage(CAImage::create("image/motor_control_view.jpg"));view1->setLayout(DLayoutFill);this->getView()->addSubview(view1);CALabel* label = CALabel::create();label->setColor(ccc4(51, 204, 255, 255));label->setText( UTF8( "网络参数设置"));label->setFontSize(36);label->setTextAlignment(CATextAlignmentLeft);label->setVerticalTextAlignmet(CAVerticalTextAlignmentCenter);label->setLayout(DLayout(DHorizontalLayout_W_C(240, 0.5), DVerticalLayout_H_C(40, 0.12)));this->getView()->addSubview(label);std::string ctn;m_textField_IP = CATextField::createWithLayout(DLayout(DHorizontalLayout_W_C(400, 0.5), DVerticalLayout_H_C(70, 0.30)));m_textField_IP->setTag(200);//PlaceHolder文本内容ctn = "IP: " +m_NetworkInfo.getIP();m_textField_IP->setPlaceHolderText(ctn);//键盘类型m_textField_IP->setKeyboardType(CATextField::Default);//TextField的对齐方式m_textField_IP->setTextFieldAlign(CATextField::Left);m_textField_IP->setDelegate(this);this->getView()->addSubview(m_textField_IP);m_textField_Port = CATextField::createWithLayout(DLayout(DHorizontalLayout_W_C(400, 0.5), DVerticalLayout_H_C(70, 0.50)));m_textField_Port->setTag(201);//PlaceHolder文本内容char str[256];sprintf(str, "Port: %d", m_NetworkInfo.getPort());ctn = std::string(str);m_textField_Port->setPlaceHolderText(ctn);//键盘类型m_textField_Port->setKeyboardType(CATextField::Default);//TextField的对齐方式m_textField_Port->setTextFieldAlign(CATextField::Left);m_textField_Port->setDelegate(this);this->getView()->addSubview(m_textField_Port);//初始化viewListm_SaveBtn = CAButton::create(CAButtonTypeRoundedRect);m_SaveBtn->setLayout(DLayout(DHorizontalLayout_W_C(240, 0.5), DVerticalLayout_T_H(600, 100)));m_SaveBtn->setTag(203);m_SaveBtn->setTitleFontSize(36);m_SaveBtn->setTitleForState(CAControlStateAll, UTF8("保存参数"));m_SaveBtn->addTarget(this, CAControl_selector(SettingsViewController::alertButtonCallBack), CAControlEventTouchUpInSide);this->getView()->addSubview(m_SaveBtn);}

修改之后，运行效果：

对于第二个bug，在
void StepMotorControlView::viewDidDisappear()函数最后，加入

    if (m_MQTTInstance){delete m_MQTTInstance;m_MQTTInstance = NULL;}

改后代码：

void StepMotorControlView::viewDidDisappear()
{if (m_MQTTInstance && m_MQTTInstance->IsHardwareStarted()){m_StepMotorHardware.setActionSate(0);SendActionMessage(m_StepMotorHardware.getIDX(), m_StepMotorHardware.getActionState(),m_StepMotorHardware.getDirection(),m_StepMotorHardware.getVelocity());m_MQTTInstance->StopHardware();}if (m_MQTTInstance){delete m_MQTTInstance;m_MQTTInstance = NULL;}
}

最后的连接效果：

四、联合开发板做测试

完整源代码：
StepMotorController_2017.10.03_VS2013 Android.rar

需要说明一下的是，这个版本因为兼容android做了一些修改，而修改后的代码也在VS2013上编译运行过，是可以的，因此，这一版支持了两个平台。

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