How to do a wrapped text finder? - c++

Question

I am working on a text finder in QtCreator(c++). I used a "QtextEdit::find" function and it finds every occurrence of the searched word until the document reaches the end, when a NEXT button is pushed. Now I want to add a "QCheckBox" that when checked restart the "finder" at the beginning of the document and continues the search.
Do you have any suggestions how to do that, considering that the "QTextEdit::find" returns a bool?
Here is the my find function:
void textFinder(const QString& textToFind, bool rev, bool wrappedSearch)
{
QTextDocument *document = this->document();
QTextCursor cursor (document);
QTextDocument::FindFlags flag;
if (rev == flag)
flag |= QTextDocument::FindBackward;
bool found = find(textToFind, flag);
if (wrappedSearch == true){
cursor.movePosition(QTextCursor::Start);
}
}
The tool bar that I did contains a QLineEdit, QPushButton, and a QCheckBox.

Answer 1

Thank you for your answears ! Those helped me a lot. For my code, it worked like this:
if (searchWrapped == true && !found){
if (rev == false && cursor.atStart() == true){
cursor.movePosition(QTextCursor::End);
found = find (text, flag);
}
if (rev && cursor.atEnd() == true){
cursor.movePosition(QTextCursor::Start);
found = find (text, flag);
}
}
setTextCursor(cursor);
}

Answer 2

If I have understood the question you want help with implementing wrapped search. Then I think it will suffice to perform another search after having moved the cursor to either start or end of document depending on whether reversed search or not:
void textFinder(const QString& textToFind, bool rev, bool wrappedSearch)
{
QTextDocument *document = this->document();
QTextCursor cursor (document);
QTextDocument::FindFlags flag;
if (rev == flag)
flag |= QTextDocument::FindBackward;
bool found = find(textToFind, flag);
if (!found&&wrappedSearch == true)
{
cursor.movePosition(rev?QTextCursor::End:QTextCursor::Start);
found = find(textToFind, flag);
}
}

Answer 3

Theres a few problems with your code and the logic inside it.
First of all, I don't understand why you are comparing your rev bool to the flag variable. Shouldn't you compare it against true? I'd also set the initial value of the flag variable to 0.
Second of all, if the wrapped search is set to true, you should only wrap it if QTextEdit::find returned false. Otherwise you'd be stuck at the beginning of the document.
Then you should also check if the value rev is true before setting the cursor to the beginning. If you are searching backwards, you should set the cursor to the end of the document when wrapping.
And you also have to set the text cursor back to your text edit after modifying it.
Here is my working search function, I didn't subclass QTextEdit because I was lazy, but the logic is the same.
void MainWindow::findText(const QString &text, bool rev, bool wrapped)
{
QTextDocument::FindFlags flag = 0;
if(rev)
flag = flag | QTextDocument::FindBackward;
bool found = ui->textEdit->find(text, flag);
if(!found && wrapped)
{
QTextCursor cursor = ui->textEdit->textCursor();
if(!rev)
cursor.movePosition(QTextCursor::Start);
else
cursor.movePosition(QTextCursor::End);
ui->textEdit->setTextCursor(cursor);
ui->textEdit->find(text, flag);
}
}