qt - Qt如何将选择移动到一行

Question

我有麻烦。这里我的代码是：

void TextEditor::moveToLineUp()
{
    QTextCursor cur = textCursor();

    if(cur.hasSelection()) {
        int start = cur.selectionStart();
        int end = cur.selectionEnd();
        QTextBlock startBlock = document()->findBlock(start);
        QTextBlock endBlock = document()->findBlock(end);

        cur.setPosition(startBlock.position());
        cur.setPosition(endBlock.position()+endBlock.length(), QTextCursor::KeepAnchor);
    } else {
        // I'll fill it later
    }

    // ??? I don't know how not to write remove action in undo stack
    QString text = cur.selectedText();
    cur.removeSelectedText();
    QTextCursor ncur(cur.block().previous());
    ncur.insertText(text);
}

当用户选择一些文本并单击“排队”按钮时，将调用此函数。有选择的每一行都应该移动到一行。但在那之后撤消堆栈必须执行以下步骤：删除文本并粘贴文本。我应该怎么办？我想一步一步让它变得简单。