CTreeCtrl：如何清除所选项目的焦点

Question

我是 MFC 的新手，我想复制准确的 Ctrl+Page Down 和 Ctrl+Page Up 常规 Page Down/Page Up 键的行为没有任何支持键（Ctrl/Shift)。我一直在尝试清除在点击 Page Up 和 Page Down.

键时自动选择的项目的焦点

我已经尝试使用此代码，但它不起作用：

case VK_NEXT:   // pagedown
case VK_PRIOR:  // pageup
    lhItem = GetFocusedItem();
    if (IsSelected(lhItem))
    {
        CTreeCtrl::SetItemState(lhItem, 0, TVIS_SELECTED);
    }
    break;

谁能帮我解决一下

Answer 1

代码需要写在 OnSelChanging 和 OnSelChanged 事件处理函数中

void CTreeCtrl::OnSelchanging(NMHDR *pNMHDR, LRESULT *pResult)
{
    HTREEITEM hNew = pNMTreeView->itemNew.hItem;
    HTREEITEM hOld = pNMTreeView->itemOld.hItem;

    m_bOldItemSelected = hOld && (CTreeCtrl::GetItemState(hOld, UINT(TVIS_SELECTED)) & TVIS_SELECTED);

if (GetSelectedCount() > 1)
{
    if (m_bPgUpState || m_bPgDownState)
    {
        //Check the state of New Item
        if ((pNMTreeView->itemNew.state & TVIS_SELECTED))
        {
            // If the item is selected, so make sure OnSelchanged()
            // will "select" it !
            m_bNewItemSelected = TRUE;
        }
        else if (!(pNMTreeView->itemNew.state & TVIS_SELECTED))
        {
            // The New item is not selected, so make sure OnSelchanged()
            // will not "re-select" it !
            m_bNewItemSelected = FALSE;
            CTreeCtrl::SetItemState(hNew, UINT(~TVIS_SELECTED), UINT(TVIS_SELECTED));
        }
    }
}

void TreeCtrl::OnSelchanged(NMHDR* pNMHDR, LRESULT* pResult)
{
    NM_TREEVIEW* pNMTreeView = (NM_TREEVIEW*)pNMHDR;

    HTREEITEM itemNew = pNMTreeView->itemNew.hItem;
    HTREEITEM itemOld = pNMTreeView->itemOld.hItem;
if ((m_bPgUpState || m_bPgDownState) && (GetSelectedCount() > 1)
    && (pNMTreeView->itemOld.hItem != NULL || pNMTreeView->itemNew.hItem != NULL))
{
    // It had the focus so Keep selection at old item
    if (itemOld && m_bOldItemSelected)
    {
        CTreeCtrl::SetItemState(itemOld, UINT(TVIS_SELECTED), UINT(TVIS_SELECTED));
        m_bOldItemSelected = FALSE;
    }
    else
    {
        // Do-not select the item if it is not selected
        CTreeCtrl::SetItemState(itemOld, UINT(~TVIS_SELECTED), UINT(TVIS_SELECTED));
    }

}

在本文中，您将找到有关 CTreeCtrl 的所有问题的解决方案 Full-Featured Tree Control

CTreeCtrl：如何清除所选项目的焦点

CTreeCtrl: How to clear the focus of selected item

mfc

visual-c++

visual-studio-2013