Duilib实现 Windows资源管理器前进后退原理

一、用两个vector保存路径

vector<wstring> vctBacks;//保存后退路径的集合

vector<wstring> vctForwards//保存前进路径集合

CButtonUI*  pBackbtn;//后退按钮

CButtonUI* pForwardbtn;//前进按钮

1.程序初始化时，两个按钮不可用状态

2.当点击一系列目录后，后退集合把这些路径保存，后退按钮设为可用状态

3.当点击后退按钮，把vctBacks最后一个元素取出来 wstring temp = vctBacks.back()，放进前进集合里 vctForwards.push_back(temp),然后后退集合删除掉最后一个 vctBacks.pop_back()

4.再点击前进按钮，把vctForwards最后一个元素取出来 wstring temp = vctForwards.back(),，放进前进集合里 vctBacks.push_back(temp),然后后退集合删除掉最后一个 vctForwards.pop_back()

5.若前进集合还有一个元素时，取出元素push到后退集合里。然后把前进按钮设为不可用；若后退集合还有一个元素时，取出元素push到前几集合里，然后把后退按钮设为不可用

 void OnClickBtnForward()
 {
     if (m_vctForwards.size() > )
     {
         if (m_vctForwards.size() == )
         {
             wstring wstr = m_vctForwards.back();
             CListLabelElementUI* pElement = (CListLabelElementUI*)(m_pLeftTree->FindSubControl(wstr.c_str()));

             if (pElement)
             {
                 pElement->Select();
             }

             m_vctBacks.push_back(wstr);
             m_vctForwards.pop_back();

             if (m_vctForwards.empty())//在此判断有点多余
             {
                 m_pForwardbtn->SetEnabled(false);
             }

             if (!m_vctBacks.empty())
             {
                 m_pBackbtn->SetEnabled(true);
             }

             m_pPath->SetText(wstr.c_str());
             m_pFileList->RemoveAll();
             InitFileList(wstr.c_str());
             return;
         }
         else
         {
             wstring  temp = m_vctForwards.back();
             m_vctBacks.push_back(temp);
             m_vctForwards.pop_back();
             temp = m_vctBacks.back();

             CListLabelElementUI* pElement = (CListLabelElementUI*)(m_pLeftTree->FindSubControl(temp.c_str()));
             if (pElement != NULL)
             {
                 pElement->Select();
             }

             if (!m_vctBacks.empty())
             {
                 m_pBackbtn->SetEnabled(true);
             }

             m_pFileList->RemoveAll();
             InitFileList(temp.c_str());
             m_pPath->SetText(temp.c_str());
         }
     }
 }

 void OnClickBtnBack()
 {
     if (m_vctBacks.size() > )
     {

         if (m_vctBacks.size() == )
         {
             wstring wstr = m_vctBacks.back();
             CListLabelElementUI* pElement = (CListLabelElementUI*)(m_pLeftTree->FindSubControl(wstr.c_str()));

             if (pElement)
             {
                 pElement->Select();
             }
             m_vctForwards.push_back(wstr);
             m_vctBacks.pop_back();
             m_pPath->SetText(_T(""));
             m_pBackbtn->SetEnabled(false);
             m_pFileList->RemoveAll();
             return;
         }
         else
         {
             wstring temp = m_vctBacks.back();
             m_vctForwards.push_back(temp);//只要执行这行代码,前进按钮就可用
             if (!m_vctForwards.empty())
             {
                 m_pForwardbtn->SetEnabled(true);
             }
             m_vctBacks.pop_back();
             temp = m_vctBacks.back();

             CListLabelElementUI* pElement = (CListLabelElementUI*)(m_pLeftTree->FindSubControl(temp.c_str()));

             if (pElement != NULL)
             {
                 pElement->Select();
             }
             m_pFileList->RemoveAll();
             InitFileList(temp.c_str());
             m_pPath->SetText(temp.c_str());
         }
     }
 }