QPlainTextEdit

Question

我想在QPlainTextEdit中搜索从当前光标到末尾的字符串。如果什么都找不到，我想从头开始继续搜索。只有在这个阶段，如果什么都没有找到，就会出现一条消息。这是代码：

void BasicEdit::findString(QString s, bool reverse, bool casesens, bool words) {
QTextDocument::FindFlags flag;
if (reverse) flag |= QTextDocument::FindBackward;
if (casesens) flag |= QTextDocument::FindCaseSensitively;
if (words) flag |= QTextDocument::FindWholeWords;

QTextCursor cursor = this->textCursor();

if (!find(s, flag)) {
    //nothing is found | jump to start/end
    cursor.movePosition(reverse?QTextCursor::End:QTextCursor::Start);
    setTextCursor(cursor); //!!!!!!
    if (!find(s, flag)) {
        //no match in whole document
        QMessageBox msgBox;
        msgBox.setText(tr("String not found."));
        msgBox.setStandardButtons(QMessageBox::Ok);
        msgBox.setDefaultButton(QMessageBox::Ok);
        msgBox.exec();
    }
  }
}

问题是行setTextCursor(cursor);

没有这一行，搜索不会从 beginning/end
对于这一行，一切都很好，除了当找不到字符串时，光标位于文档的开头/结尾，并且用户在文档中的当前位置丢失。

如何在文档中搜索字符串并且如果找到 none 则不更改当前位置？

更新

感谢 IAmInPLS，代码如下所示。我为 verticalScrollBar 添加了保值。即便如此，当没有发现生成的内容时，会出现短暂的闪烁：cursor.movePosition(reverse?QTextCursor::End:QTextCursor::Start);

我们怎样才能摆脱它？怎样才能看起来像专业的编辑？创建另一个不可见的 QPlainTextEdit 元素以在其中搜索是一个想法吗？

void BasicEdit::findString(QString s, bool reverse, bool casesens, bool words)
{
QTextDocument::FindFlags flag;
if (reverse) flag |= QTextDocument::FindBackward;
if (casesens) flag |= QTextDocument::FindCaseSensitively;
if (words) flag |= QTextDocument::FindWholeWords;

QTextCursor cursor = this->textCursor();
// here we save the cursor position and the verticalScrollBar value
QTextCursor cursorSaved = cursor;
int scroll = verticalScrollBar()->value();

if (!find(s, flag))
{
    //nothing is found | jump to start/end
    cursor.movePosition(reverse?QTextCursor::End:QTextCursor::Start);
    setTextCursor(cursor);

    if (!find(s, flag))
    {
        // word not found : we set the cursor back to its initial position and restore verticalScrollBar value
        setTextCursor(cursorSaved);
        verticalScrollBar()->setValue(scroll);
        QMessageBox msgBox(this);
        msgBox.setText(tr("String not found."));
        msgBox.setStandardButtons(QMessageBox::Ok);
        msgBox.setDefaultButton(QMessageBox::Ok);
        msgBox.exec();
    }
}
}

Answer 1

想法是在开始搜索单词之前保持光标位置。然后，在研究之后，你将光标设置回你保存的位置。

void BasicEdit::findString(QString s, bool reverse, bool casesens, bool words) { QTextDocument::FindFlags flag; if (reverse) flag |= QTextDocument::FindBackward; if (casesens) flag |= QTextDocument::FindCaseSensitively; if (words) flag |= QTextDocument::FindWholeWords; QTextCursor cursor = this->textCursor(); // here , you save the cursor position QTextCursor cursorSaved = cursor; if (!find(s, flag)) { //nothing is found | jump to start/end cursor.movePosition(reverse?QTextCursor::End:QTextCursor::Start); /* following line : - the cursor is set at the beginning/end of the document (if search is reverse or not) - in the next "find", if the word is found, now you will change the cursor position */ setTextCursor(cursor); if (!find(s, flag)) { //no match in whole document QMessageBox msgBox; msgBox.setText(tr("String not found.")); msgBox.setStandardButtons(QMessageBox::Ok); msgBox.setDefaultButton(QMessageBox::Ok); msgBox.exec(); // word not found : we set the cursor back to its initial position setTextCursor(cursorSaved); } } }

QPlainTextEdit - 搜索文档到最后，然后再从头开始

QPlainTextEdit - searches the document to the end and again from the beginning

c++

qt

find

qtextcursor

更新