Design Patterns 5 - 观察者模式 Observer

Design Patterns 5 -  观察者模式 Observer

https://www.bilibili.com/video/BV1kW411P7KS?p=5

 

都是亲手敲出来的，转载请注明出处，谢谢。

 

https://www.bilibili.com/video/BV1kW411P7KS?p=5

//FileSpliter.cpp
class FileSpliter{
    string m_filePath;
    int m_fileNumber;
    
public:
    FileSpliter(const string &filePath, int fileNumber):
        m_filePath(filePath),
        m_fileNumber(fileNumber){
    
    }
    
    void split(){
        //1. 读取文件
        
        //2. 分批次想小文件写入
        for (int i = 0; i < m_fileNumber; i++){
            //...
            
        }
    }
};


//MainForm.cpp
class MainForm : public Form{
    Text * textFilePath;
    Text * textFileNumber;
    
public:
    void Button1_Click(){
        string filePath = textFilePath->getText();
        int number = atoi(textFileNumber->getText.c_str());
        
        FileSpliter spliter(filePath, number);
        
        spliter.split();
    }
};


//FileSpliter1.cpp
//有什么问题?
//违背依赖倒置原则
class FileSpliter{
    string m_filePath;
    int m_fileNumber;
    
    ProgressBar *m_progressBar; //编译时依赖，实现细节
    
public:
    FileSpliter(const string &filePath, int fileNumber, ProgressBar *progressBar):
        m_filePath(filePath),
        m_fileNumber(fileNumber),
        m_progressBar(progressBar){
    
    }
    
    void split(){
        //1. 读取文件
        
        //2. 分批次想小文件写入
        for (int i = 0; i < m_fileNumber; i++){
            //...
            if(NULL != m_progressBar{
                m_progressBar->setValue((i + 1) / m_fileNumber); //更新进度条
            }
        }
    }
};


//MainForm1.cpp
//需求：增加进度条
class MainForm : public Form{
    Text * textFilePath;
    Text * textFileNumber;
    
    ProgressBar * progressBar;

public:
    void Button1_Click(){
        string filePath = textFilePath->getText();
        int number = atoi(textFileNumber->getText.c_str());
        
        FileSpliter spliter(filePath, number, progressBar);
        
        spliter.split();
    }
};


//FileSpliter2.cpp
//有什么问题?
//违背依赖倒置原则

//不依赖于具体的界面

class IPrgress{
public:
    virtual void DoProgress(float progressValue) = 0;
    virtual ~IPrgress(){}
};

class FileSpliter{
    string m_filePath;
    int m_fileNumber;
    
    //ProgressBar *m_progressBar; //具体通知控件
    IPrgress* m_iprogress; //抽象通知机制，最大的重点
    
public:
    FileSpliter(const string &filePath, int fileNumber, IPrgress* iprogress):
        m_filePath(filePath),
        m_fileNumber(fileNumber),
        m_iprogress(iprogress){
    
    }
    
    void split(){
        //1. 读取文件
        
        //2. 分批次想小文件写入
        for (int i = 0; i < m_fileNumber; i++){
            //...
            if(NULL != m_iprogress{
                float progressValue = m_fileNumber;
                progressValue = (i + 1) / m_fileNumber;
                onProgress(progressValue);
            }
        }
    }

protected:
    void onProgress(float value){
        if(NULL != m_iprogress{
            m_progressBar->DoProgress(progressValue); //更新进度条
        }
    }
};


//MainForm2.cpp
//需求：增加进度条

//C++支持多继承，推荐一个主继承类，其他都是接口
//MainForm和ProgressBar是一体的
class MainForm : public Form, public IProgress{
    Text * textFilePath;
    Text * textFileNumber;
    
    ProgressBar * progressBar;

public:
    void Button1_Click(){
        string filePath = textFilePath->getText();
        int number = atoi(textFileNumber->getText.c_str());
        
        FileSpliter spliter(filePath, number, this);
        
        spliter.split();
    }
    virtual void DoProgress(float progressValue){
        progressBar->setValue(value);
    }
};


//FileSpliter3.cpp
//有什么问题?
//违背依赖倒置原则

//不依赖于具体的界面

class IPrgress{
public:
    virtual void DoProgress(float progressValue) = 0;
    virtual ~IPrgress(){}
};

class FileSpliter{
    string m_filePath;
    int m_fileNumber;
    
    //ProgressBar *m_progressBar; //具体通知控件
    List<IPrgress*> m_iprogressList; //抽象通知机制，最大的重点
    
public:
    FileSpliter(const string &filePath, int fileNumber, IPrgress* iprogress):
        m_filePath(filePath),
        m_fileNumber(fileNumber),
        m_iprogress(iprogress){
    
    }

    void split(){
        //1. 读取文件
        
        //2. 分批次想小文件写入
        for (int i = 0; i < m_fileNumber; i++){
            //...
            if(NULL != m_iprogress{
                float progressValue = m_fileNumber;
                progressValue = (i + 1) / m_fileNumber;
                onProgress(progressValue);
            }
        }
    }
    
    void addIProgress(IPrgress *iprogress){ //attach
        m_iprogressList.add(iprogress)
    }

    void removeIProgress(IPrgress *iprogress){ //detatch
        m_iprogressList.remove(iprogress)
    }

protected:
    void onProgress(float value){  //Notify
        List<IPrgress*>::Iterator itor = m_iprogressList.begin();
        while(itor != m_iprogressList.end())
            (*itor)->DoProgress(value);
    }
};



//MainForm3.cpp
//需求：增加进度条

//C++支持多继承，推荐一个主继承类，其他都是接口
//MainForm和ProgressBar是一体的
class MainForm : public Form, public IProgress{
    Text * textFilePath;
    Text * textFileNumber;
    
    ProgressBar * progressBar;

public:
    void Button1_Click(){
        string filePath = textFilePath->getText();
        int number = atoi(textFileNumber->getText.c_str());
        
        ConsleNotifier cn;
        FileSpliter spliter(filePath, number);

        spliter.addIProgress(this); //订阅通知
        spliter.addIProgress(&cn); //订阅通知
    }
    
    virtual void DoProgress(float progressValue){
        progressBar->setValue(value);
    }
};

class ConsleNotifier : public IProgress{
public:
    virtual void DoProgress(float progressValue){
        cout<<".";
    }
}；

 

 

https://www.bilibili.com/video/BV1kW411P7KS?p=5
//FileSpliter.cppclass FileSpliter{    string m_filePath;    int m_fileNumber;    public:    FileSpliter(const string &filePath, int fileNumber):        m_filePath(filePath),        m_fileNumber(fileNumber){        }        void split(){        //1. 读取文件                //2. 分批次想小文件写入        for (int i = 0; i < m_fileNumber; i++){            //...                    }    }};

//MainForm.cppclass MainForm : public Form{    Text * textFilePath;    Text * textFileNumber;    public:    void Button1_Click(){        string filePath = textFilePath->getText();        int number = atoi(textFileNumber->getText.c_str());                FileSpliter spliter(filePath, number);                spliter.split();    }};

//FileSpliter1.cpp//有什么问题?//违背依赖倒置原则class FileSpliter{    string m_filePath;    int m_fileNumber;        ProgressBar *m_progressBar; //编译时依赖，实现细节    public:    FileSpliter(const string &filePath, int fileNumber, ProgressBar *progressBar):        m_filePath(filePath),        m_fileNumber(fileNumber),        m_progressBar(progressBar){        }        void split(){        //1. 读取文件                //2. 分批次想小文件写入        for (int i = 0; i < m_fileNumber; i++){            //...            if(NULL != m_progressBar{                m_progressBar->setValue((i + 1) / m_fileNumber); //更新进度条            }        }    }};

//MainForm1.cpp//需求：增加进度条class MainForm : public Form{    Text * textFilePath;    Text * textFileNumber;        ProgressBar * progressBar;
public:    void Button1_Click(){        string filePath = textFilePath->getText();        int number = atoi(textFileNumber->getText.c_str());                FileSpliter spliter(filePath, number, progressBar);                spliter.split();    }};

//FileSpliter2.cpp//有什么问题?//违背依赖倒置原则
//不依赖于具体的界面
class IPrgress{public:    virtual void DoProgress(float progressValue) = 0;    virtual ~IPrgress(){}};
class FileSpliter{    string m_filePath;    int m_fileNumber;        //ProgressBar *m_progressBar; //具体通知控件    IPrgress* m_iprogress; //抽象通知机制，最大的重点    public:    FileSpliter(const string &filePath, int fileNumber, IPrgress* iprogress):        m_filePath(filePath),        m_fileNumber(fileNumber),        m_iprogress(iprogress){        }        void split(){        //1. 读取文件                //2. 分批次想小文件写入        for (int i = 0; i < m_fileNumber; i++){            //...            if(NULL != m_iprogress{                float progressValue = m_fileNumber;                progressValue = (i + 1) / m_fileNumber;                onProgress(progressValue);            }        }    }
protected:    void onProgress(float value){        if(NULL != m_iprogress{            m_progressBar->DoProgress(progressValue); //更新进度条        }    }};

//MainForm2.cpp//需求：增加进度条
//C++支持多继承，推荐一个主继承类，其他都是接口//MainForm和ProgressBar是一体的class MainForm : public Form, public IProgress{    Text * textFilePath;    Text * textFileNumber;        ProgressBar * progressBar;
public:    void Button1_Click(){        string filePath = textFilePath->getText();        int number = atoi(textFileNumber->getText.c_str());                FileSpliter spliter(filePath, number, this);                spliter.split();    }    virtual void DoProgress(float progressValue){        progressBar->setValue(value);    }};

//FileSpliter3.cpp//有什么问题?//违背依赖倒置原则
//不依赖于具体的界面
class IPrgress{public:    virtual void DoProgress(float progressValue) = 0;    virtual ~IPrgress(){}};
class FileSpliter{    string m_filePath;    int m_fileNumber;        //ProgressBar *m_progressBar; //具体通知控件    List<IPrgress*> m_iprogressList; //抽象通知机制，最大的重点    public:    FileSpliter(const string &filePath, int fileNumber, IPrgress* iprogress):        m_filePath(filePath),        m_fileNumber(fileNumber),        m_iprogress(iprogress){        }
    void split(){        //1. 读取文件                //2. 分批次想小文件写入        for (int i = 0; i < m_fileNumber; i++){            //...            if(NULL != m_iprogress{                float progressValue = m_fileNumber;                progressValue = (i + 1) / m_fileNumber;                onProgress(progressValue);            }        }    }        void addIProgress(IPrgress *iprogress){ //attach        m_iprogressList.add(iprogress)    }
    void removeIProgress(IPrgress *iprogress){ //detatch        m_iprogressList.remove(iprogress)    }
protected:    void onProgress(float value){  //Notify        List<IPrgress*>::Iterator itor = m_iprogressList.begin();        while(itor != m_iprogressList.end())            (*itor)->DoProgress(value);    }};


//MainForm3.cpp//需求：增加进度条
//C++支持多继承，推荐一个主继承类，其他都是接口//MainForm和ProgressBar是一体的class MainForm : public Form, public IProgress{    Text * textFilePath;    Text * textFileNumber;        ProgressBar * progressBar;
public:    void Button1_Click(){        string filePath = textFilePath->getText();        int number = atoi(textFileNumber->getText.c_str());                ConsleNotifier cn;        FileSpliter spliter(filePath, number);
        spliter.addIProgress(this); //订阅通知        spliter.addIProgress(&cn); //订阅通知    }        virtual void DoProgress(float progressValue){        progressBar->setValue(value);    }};
class ConsleNotifier : public IProgress{public:    virtual void DoProgress(float progressValue){        cout<<".";    }}；