MFC Controls: Tree controls (CTreeCtrl)

Tree-shaped control partitioning:

Root node: All nodes that have been shrunk

Node: able to expand

Leaf: Cannot unfold

Note: Nodes and leaves are not absolute divisions, and when a new subordinate is added to a leaf, the leaf becomes a node

The tree controls are added:

node struct: htreeitem, declaring the node variable with the struct body

To add an item to a control:

htreeitem InsertItem (lpctstr lpszitem,  　　　　　　　　　　//Item name int nImage,  // Index of the image of an item in the tree view Control image list int nselectedimage,  //tree view Control the index of the selected image of an item in the image list Htreeitem hparent = tvi_ ROOT,  //Insert The handle of the item to be inserted before the parent's handle//new item );
Note: Before adding an item, set the root node before initializing the

Tree control Mouse click:

　　Determine the mouse position

Htreeitem Cmytreedlg::getselecttree () {    CPoint pt;    GetCursorPos (&pt); // get the current mouse position    M_mytree.screentoclient (&PT); // Convert screen coordinates to client area coordinates    Htreeitem Tree_item = M_mytree.hittest (PT); // call HitTest to find the tree node    corresponding to the click return Tree_item;//return mouse position node}

Get an item of text

CString GetItemText (Htreeitem hItem) const;

Gets the specified relationship item

Htreeitem GetNextItem (Htreeitem hItem, UINT nCode) const;

　　nCodeThe flag can be one of the following values: TVGN_CARET retrieves the currently selected item . TVGN_CHILDretrieves the first subproject parameter by the specified item hItem . Retrieves the item that is the TVGN_DROPHILITE target of a drag-and-drop operation . TVGN_FIRSTVISIBLEretrieves the first visible item . TVGN_LASTVISIBLEretrieves the last expanded item in the tree. This does not retrieve the last item visible in the tree view window . TVGN_NEXTretrieves the next sibling . TVGN_NEXTVISIBLEretrieves the next visible item that follows the specified item . TVGN_PARENTretrieves the parent of the specified item . TVGN_PREVIOUSretrieves the preceding sibling . TVGN_PREVIOUSVISIBLEretrieves the first visible item that is located in the specified item. TVGN_ROOTretrieves the first child item of a root item that is part of a specified item.

Gets the parent of the specified item

Htreeitem GetParentItem (Htreeitem hItem) const;

MFC Controls: Tree controls (CTreeCtrl)