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。

 1 if( uMsg == WM_CREATE ) {

 2             m_pm.Init(m_hWnd);

 3             //根据XML创建控件

 4             CDialogBuilder builder;

 5             CControlUI* pRoot = builder.Create(_T("HelloWorld.xml"), (UINT)0, NULL, &m_pm);

 6             ASSERT(pRoot && "Failed to parse XML");

 7             m_pm.AttachDialog(pRoot);

 8             m_pm.AddNotifier(this);

 9             return 0;

10         }

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

   1 CControlUI* CDialogBuilder::Create(STRINGorID xml, LPCTSTR type, IDialogBuilderCallback* pCallback, 
  
   2                                    CPaintManagerUI* pManager, CControlUI* pParent)
  
   3 {
  
   4     if( HIWORD(xml.m_lpstr) != NULL ) {
  
   5         if( *(xml.m_lpstr) == _T('<') ) {
  
   6             if( !m_xml.Load(xml.m_lpstr) ) return NULL;
  
   7         }
  
   8         else {
  
   9             if( !m_xml.LoadFromFile(xml.m_lpstr) ) return NULL; 10         }
  
  11     }
  
  12     else {
  
  13         HRSRC hResource = ::FindResource(CPaintManagerUI::GetResourceDll(), xml.m_lpstr, type);
  
  14         if( hResource == NULL ) return NULL;
  
  15         HGLOBAL hGlobal = ::LoadResource(CPaintManagerUI::GetResourceDll(), hResource);
  
  16         if( hGlobal == NULL ) {
  
  17             FreeResource(hResource);
  
  18             return NULL;
  
  19         }
  
  20 
  
  21         m_pCallback = pCallback;
  
  22         if( !m_xml.LoadFromMem((BYTE*)::LockResource(hGlobal), ::SizeofResource(CPaintManagerUI::GetResourceDll(), hResource) )) return NULL;
  
  23         ::FreeResource(hResource);
  
  24         m_pstrtype = type;
  
  25     }
  
  26 
  
  27     return Create(pCallback, pManager);
  
  28 }

• 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）

   1 CControlUI* CDialogBuilder::Create(IDialogBuilderCallback* pCallback, CPaintManagerUI* pManager, CControlUI* pParent)
  
   2 {
  
   3     m_pCallback = pCallback;//回调函数，用于创建自定义控件
  
   4     CMarkupNode root = m_xml.GetRoot();
  
   5     if( !root.IsValid() ) return NULL;
  
   6 
  
   7     if( pManager ) {
  
   8         LPCTSTR pstrClass = NULL;
  
   9         int nAttributes = 0;
  
  10         LPCTSTR pstrName = NULL;
  
  11         LPCTSTR pstrValue = NULL;
  
  12         LPTSTR pstr = NULL;
  
  13         for( CMarkupNode node = root.GetChild() ; node.IsValid(); node = node.GetSibling() ) {
  
  14             pstrClass = node.GetName();
  
  15             if( _tcscmp(pstrClass, _T("Image")) == 0 ) {//Image
  
  16             }
  
  17             else if( _tcscmp(pstrClass, _T("Font")) == 0 ) {//Font
  
  18             }
  
  19             else if( _tcscmp(pstrClass, _T("Default")) == 0 ) {//Default
  
  20             }
  
  21         }
  
  22 
  
  23         pstrClass = root.GetName();
  
  24         if( _tcscmp(pstrClass, _T("Window")) == 0 ) {//Window
  
  25         }
  
  26     }
  
  27     return _Parse(&root, NULL, pManager); 28 }

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

     1 。。。。。。
    
     2 if( _tcscmp(pstrClass, _T("Include")) == 0 ) {//Include
    
     3             if( !node.HasAttributes() ) continue;
    
     4             int count = 1;
    
     5             LPTSTR pstr = NULL;
    
     6             TCHAR szValue[500] = { 0 };
    
     7             SIZE_T cchLen = lengthof(szValue) - 1;
    
     8             if ( node.GetAttributeValue(_T("count"), szValue, cchLen) )
    
     9                 count = _tcstol(szValue, &pstr, 10);
    
    10             cchLen = lengthof(szValue) - 1;
    
    11             if ( !node.GetAttributeValue(_T("source"), szValue, cchLen) ) continue;
    
    12             for ( int i = 0; i < count; i++ ) {
    
    13                 CDialogBuilder builder;
    
    14                 if( m_pstrtype != NULL ) { // 使用资源dll，从资源中读取
    
    15                     WORD id = (WORD)_tcstol(szValue, &pstr, 10); 
    
    16                     pControl = builder.Create((UINT)id, m_pstrtype, m_pCallback, pManager, pParent);
    
    17                 }
    
    18                 else {
    
    19                     pControl = builder.Create((LPCTSTR)szValue, (UINT)0, m_pCallback, pManager, pParent); 20                 }
    
    21             }
    
    22             continue;
    
    23         }
    
    24 。。。。。。

  • 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 4:
    
                    if( _tcscmp(pstrClass, _T("Edit")) == 0 )                   pControl = new CEditUI;
    
                    else if( _tcscmp(pstrClass, _T("List")) == 0 )              pControl = new CListUI;
    
                    else if( _tcscmp(pstrClass, _T("Text")) == 0 )              pControl = new CTextUI;
    
                    break;
    
                case 5:
    
                    if( _tcscmp(pstrClass, _T("Combo")) == 0 )                  pControl = new CComboUI;
    
                    else if( _tcscmp(pstrClass, _T("Label")) == 0 )             pControl = new CLabelUI;
    
                    break;
    
                case 6:
    
                    if( _tcscmp(pstrClass, _T("Button")) == 0 )                 pControl = new CButtonUI;
    
                    else if( _tcscmp(pstrClass, _T("Option")) == 0 )            pControl = new COptionUI;
    
                    else if( _tcscmp(pstrClass, _T("Slider")) == 0 )            pControl = new CSliderUI;
    
                    break;
    
                case 7:
    
                    if( _tcscmp(pstrClass, _T("Control")) == 0 )                pControl = new CControlUI;
    
                    else if( _tcscmp(pstrClass, _T("ActiveX")) == 0 )           pControl = new CActiveXUI;
    
                    break;
    
                case 8:
    
                    if( _tcscmp(pstrClass, _T("Progress")) == 0 )               pControl = new CProgressUI;
    
                    else if(  _tcscmp(pstrClass, _T("RichEdit")) == 0 )         pControl = new CRichEditUI;
    
                    break;
    
                case 9:
    
                    if( _tcscmp(pstrClass, _T("Container")) == 0 )              pControl = new CContainerUI;
    
                    else if( _tcscmp(pstrClass, _T("TabLayout")) == 0 )         pControl = new CTabLayoutUI;
    
                    else if( _tcscmp(pstrClass, _T("ScrollBar")) == 0 )         pControl = new CScrollBarUI; 
    
                    break;
    
                case 10:
    
                    if( _tcscmp(pstrClass, _T("ListHeader")) == 0 )             pControl = new CListHeaderUI;
    
                    else if( _tcscmp(pstrClass, _T("TileLayout")) == 0 )        pControl = new CTileLayoutUI;
    
                    break;
    
                case 12:
    
                    if( _tcscmp(pstrClass, _T("DialogLayout")) == 0 )           pControl = new CDialogLayoutUI;
    
                    break;
    
                case 14:
    
                    if( _tcscmp(pstrClass, _T("VerticalLayout")) == 0 )         pControl = new CVerticalLayoutUI;
    
                    else if( _tcscmp(pstrClass, _T("ListHeaderItem")) == 0 )    pControl = new CListHeaderItemUI;
    
                    break;
    
                case 15:
    
                    if( _tcscmp(pstrClass, _T("ListTextElement")) == 0 )        pControl = new CListTextElementUI;
    
                    break;
    
                case 16:
    
                    if( _tcscmp(pstrClass, _T("HorizontalLayout")) == 0 )       pControl = new CHorizontalLayoutUI;
    
                    else if( _tcscmp(pstrClass, _T("ListLabelElement")) == 0 )  pControl = new CListLabelElementUI;
    
                    break;
    
                case 20:
    
                    if( _tcscmp(pstrClass, _T("ListContainerElement")) == 0 )   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）

     1 。。。。。。
    
     2 // Add children
    
     3         if( node.HasChildren() ) {
    
     4             _Parse(&node, pControl, pManager);  5         }
    
     6         // Attach to parent
    
     7         // 因为某些属性和父窗口相关，比如selected，必须先Add到父窗口
    
     8         if( pParent != NULL ) {
    
     9             if( pContainer == NULL ) pContainer = static_cast<IContainerUI*>(pParent->GetInterface(_T("IContainer")));
    
    10             ASSERT(pContainer);
    
    11             if( pContainer == NULL ) return NULL;
    
    12             if( !pContainer->Add(pControl) ) { 13                 delete pControl;
    
    14                 continue;
    
    15             }
    
    16         }
    
    17 。。。。。。

  • 返回根控件

  • 1 。。。。。。
    
    2 // Return first item
    
    3         if( pReturn == NULL ) pReturn = pControl;
    
    4 。。。。。。

 控件创建基本就这些，下一篇写控件消息。