DuiLib（二）——控件创建

上一篇讲了窗口及消息，了解了大体的程序框架。这一篇说的是控件的创建。

duilib支持XML配置文件，即根据XML创建窗口及控件，将界面与逻辑分开，便于修改及维护。上一篇的示例中可以看到在消息WM_CREATE中有控件创建的相关代码。

 if( uMsg == WM_CREATE ) {
             m_pm.Init(m_hWnd);
             //根据XML创建控件
             CDialogBuilder builder;
             CControlUI* pRoot = builder.Create(_T("HelloWorld.xml"), (UINT), NULL, &m_pm);
             ASSERT(pRoot && "Failed to parse XML");
             m_pm.AttachDialog(pRoot);
             m_pm.AddNotifier(this);
             return ;
         }

控件创建主要牵扯到类CDialogBuilder：

• 创建控件树，返回根控件：CDialogBuilder::Create
• 将控件树关联到CPaintManagerUI对象（由名字可猜出其功能与绘制控件有关）：CPaintManagerUI::AttachDialog
• 添加消息通知：CPaintManagerUI::AddNotifier

创建控件树：

• 读取XML配置文件

   CControlUI* CDialogBuilder::Create(STRINGorID xml, LPCTSTR type, IDialogBuilderCallback* pCallback,
                                      CPaintManagerUI* pManager, CControlUI* pParent)
   {
       if( HIWORD(xml.m_lpstr) != NULL ) {
           if( *(xml.m_lpstr) == _T('<') ) {
               if( !m_xml.Load(xml.m_lpstr) ) return NULL;
           }
           else {
               if( !m_xml.LoadFromFile(xml.m_lpstr) ) return NULL;
           }
       }
       else {
           HRSRC hResource = ::FindResource(CPaintManagerUI::GetResourceDll(), xml.m_lpstr, type);
           if( hResource == NULL ) return NULL;
           HGLOBAL hGlobal = ::LoadResource(CPaintManagerUI::GetResourceDll(), hResource);
           if( hGlobal == NULL ) {
               FreeResource(hResource);
               return NULL;
           }
  
           m_pCallback = pCallback;
           if( !m_xml.LoadFromMem((BYTE*)::LockResource(hGlobal), ::SizeofResource(CPaintManagerUI::GetResourceDll(), hResource) )) return NULL;
           ::FreeResource(hResource);
           m_pstrtype = type;
       }
  
       return Create(pCallback, pManager);
   }

• 解析Image（图片）、Font（字体）、Default（默认属性）、Windows（窗口相关）项（代码太长，省略了细节）

   CControlUI* CDialogBuilder::Create(IDialogBuilderCallback* pCallback, CPaintManagerUI* pManager, CControlUI* pParent)
   {
       m_pCallback = pCallback;//回调函数，用于创建自定义控件
       CMarkupNode root = m_xml.GetRoot();
       if( !root.IsValid() ) return NULL;
  
       if( pManager ) {
           LPCTSTR pstrClass = NULL;
           int nAttributes = ;
           LPCTSTR pstrName = NULL;
           LPCTSTR pstrValue = NULL;
           LPTSTR pstr = NULL;
           for( CMarkupNode node = root.GetChild() ; node.IsValid(); node = node.GetSibling() ) {
               pstrClass = node.GetName();
               if( _tcscmp(pstrClass, _T("Image")) ==  ) {//Image
               }
               else if( _tcscmp(pstrClass, _T("Font")) ==  ) {//Font
               }
               else if( _tcscmp(pstrClass, _T("Default")) ==  ) {//Default
               }
           }
  
           pstrClass = root.GetName();
           if( _tcscmp(pstrClass, _T("Window")) ==  ) {//Window
           }
       }
       return _Parse(&root, NULL, pManager);
   }

• 创建控件：CDialogBuilder::_Parse
  • 可以通过include嵌套XML文件

     。。。。。。
     if( _tcscmp(pstrClass, _T("Include")) ==  ) {//Include
                 if( !node.HasAttributes() ) continue;
                 int count = ;
                 LPTSTR pstr = NULL;
                 TCHAR szValue[] = {  };
                 SIZE_T cchLen = lengthof(szValue) - ;
                 if ( node.GetAttributeValue(_T("count"), szValue, cchLen) )
                     count = _tcstol(szValue, &pstr, );
                 cchLen = lengthof(szValue) - ;
                 if ( !node.GetAttributeValue(_T("source"), szValue, cchLen) ) continue;
                 for ( int i = ; i < count; i++ ) {
                     CDialogBuilder builder;
                     if( m_pstrtype != NULL ) { // 使用资源dll，从资源中读取
                         WORD id = (WORD)_tcstol(szValue, &pstr, );
                         pControl = builder.Create((UINT)id, m_pstrtype, m_pCallback, pManager, pParent);
                     }
                     else {
                         pControl = builder.Create((LPCTSTR)szValue, (UINT), m_pCallback, pManager, pParent);
                     }
                 }
                 continue;
             }
     。。。。。。

  • 创建控件（自定义控件调用回调函数实现）

    。。。。。。
    else {//新建控件
                SIZE_T cchLen = _tcslen(pstrClass);
                switch( cchLen ) {
                case :
                    if( _tcscmp(pstrClass, _T("Edit")) ==  )                   pControl = new CEditUI;
                    else if( _tcscmp(pstrClass, _T("List")) ==  )              pControl = new CListUI;
                    else if( _tcscmp(pstrClass, _T("Text")) ==  )              pControl = new CTextUI;
                    break;
                case :
                    if( _tcscmp(pstrClass, _T("Combo")) ==  )                  pControl = new CComboUI;
                    else if( _tcscmp(pstrClass, _T("Label")) ==  )             pControl = new CLabelUI;
                    break;
                case :
                    if( _tcscmp(pstrClass, _T("Button")) ==  )                 pControl = new CButtonUI;
                    else if( _tcscmp(pstrClass, _T("Option")) ==  )            pControl = new COptionUI;
                    else if( _tcscmp(pstrClass, _T("Slider")) ==  )            pControl = new CSliderUI;
                    break;
                case :
                    if( _tcscmp(pstrClass, _T("Control")) ==  )                pControl = new CControlUI;
                    else if( _tcscmp(pstrClass, _T("ActiveX")) ==  )           pControl = new CActiveXUI;
                    break;
                case :
                    if( _tcscmp(pstrClass, _T("Progress")) ==  )               pControl = new CProgressUI;
                    else if(  _tcscmp(pstrClass, _T("RichEdit")) ==  )         pControl = new CRichEditUI;
                    break;
                case :
                    if( _tcscmp(pstrClass, _T("Container")) ==  )              pControl = new CContainerUI;
                    else if( _tcscmp(pstrClass, _T("TabLayout")) ==  )         pControl = new CTabLayoutUI;
                    else if( _tcscmp(pstrClass, _T("ScrollBar")) ==  )         pControl = new CScrollBarUI;
                    break;
                case :
                    if( _tcscmp(pstrClass, _T("ListHeader")) ==  )             pControl = new CListHeaderUI;
                    else if( _tcscmp(pstrClass, _T("TileLayout")) ==  )        pControl = new CTileLayoutUI;
                    break;
                case :
                    if( _tcscmp(pstrClass, _T("DialogLayout")) ==  )           pControl = new CDialogLayoutUI;
                    break;
                case :
                    if( _tcscmp(pstrClass, _T("VerticalLayout")) ==  )         pControl = new CVerticalLayoutUI;
                    else if( _tcscmp(pstrClass, _T("ListHeaderItem")) ==  )    pControl = new CListHeaderItemUI;
                    break;
                case :
                    if( _tcscmp(pstrClass, _T("ListTextElement")) ==  )        pControl = new CListTextElementUI;
                    break;
                case :
                    if( _tcscmp(pstrClass, _T("HorizontalLayout")) ==  )       pControl = new CHorizontalLayoutUI;
                    else if( _tcscmp(pstrClass, _T("ListLabelElement")) ==  )  pControl = new CListLabelElementUI;
                    break;
                case :
                    if( _tcscmp(pstrClass, _T("ListContainerElement")) ==  )   pControl = new CListContainerElementUI;
                    break;
                }
                // User-supplied control factory
                if( pControl == NULL && m_pCallback != NULL ) {
                    pControl = m_pCallback->CreateControl(pstrClass);
                }
            }
    。。。。。。

  • 添加子控件（解析子控件：递归调用_Parse、关联到父控件：CContainerUI::Add）

     。。。。。。
     // Add children
             if( node.HasChildren() ) {
                 _Parse(&node, pControl, pManager);
             }
             // Attach to parent
             // 因为某些属性和父窗口相关，比如selected，必须先Add到父窗口
             if( pParent != NULL ) {
                 if( pContainer == NULL ) pContainer = static_cast<IContainerUI*>(pParent->GetInterface(_T("IContainer")));
                 ASSERT(pContainer);
                 if( pContainer == NULL ) return NULL;
                 if( !pContainer->Add(pControl) ) {
                     delete pControl;
                     continue;
                 }
             }
     。。。。。。

  • 返回根控件

  •  。。。。。。
     // Return first item
             if( pReturn == NULL ) pReturn = pControl;
     。。。。。。

控件创建基本就这些，下一篇写控件消息。