// This creates a find-next-prompt dialog if needed.
m_find = new KFind(pattern, options, this);

// Connect textFound() signal to code which handles highlighting of found text.
connect(m_find, &KFind::textFound, this, [this](const QString &text, int matchingIndex, int matchedLength) {
    slotHighlight(text, matchingIndex, matchedLength);
}));
// Connect findNext signal - called when pressing the button in the dialog
connect(m_find, SIGNAL(findNext()),
        this, SLOT(slotFindNext()));

void slotFindNext()
{
    KFind::Result res = KFind::NoMatch;
    while (res == KFind::NoMatch && <position not at end>) {
        if (m_find->needData())
            m_find->setData(<current text fragment>);

        // Let KFind inspect the text fragment, and display a dialog if a match is found
        res = m_find->find();

        if (res == KFind::NoMatch) {
            <Move to the next text fragment, honoring the FindBackwards setting for the direction>
        }
    }

    if (res == KFind::NoMatch) // i.e. at end
        <Call either  m_find->displayFinalDialog(); m_find->deleteLater(); m_find = nullptr;
         or           if (m_find->shouldRestart()) { reinit (w/o FromCursor); m_find->resetCounts(); slotFindNext(); }
                      else { m_find->closeFindNextDialog(); }>
}

Member Function Documentation

KFind::KFind(const QString &pattern, long options, QWidget *parent)

Only use this constructor if you don't use KFindDialog, or if you use it as a modal dialog.

KFind::KFind(const QString &pattern, long options, QWidget *parent, QWidget *findDialog)

This is the recommended constructor if you also use KFindDialog (non-modal). You should pass the pointer to it here, so that when a message box appears it has the right parent. Don't worry about deletion, KFind will notice if the find dialog is closed.

void KFind::closeFindNextDialog()

Close the "find next?" dialog. The application should do this when the last match was hit. If the application deletes the KFind, then "find previous" won't be possible anymore.

IMPORTANT: you should also call this if you are using a non-modal find dialog, to tell KFind not to pop up its own dialog.

[signal] void KFind::dialogClosed()

Emitted when the 'find next' dialog is being closed. Some apps might want to remove the highlighted text when this happens. Apps without support for "Find Next" can also do m_find->deleteLater() to terminate the find operation.

[virtual] void KFind::displayFinalDialog() const

Displays the final dialog saying "no match was found", if that was the case. Call either this or shouldRestart().

KFind::Result KFind::find()

Walk the text fragment (e.g. in a text-processor line or spreadsheet cell ...etc) looking for matches. For each match, emits the textFound() signal and displays the find-again dialog to ask if the user wants to find the same text again.

[static, since 5.70] int KFind::find(const QString &text, const QString &pattern, int index, long options, int *matchedLength, QRegularExpressionMatch *rmatch)

Search text for pattern. If a match is found, the length of the matched string will be stored in matchedLength and the index of the matched string will be returned. If no match is found -1 is returned.

If the KFind::RegularExpression flag is set, the pattern will be iterpreted as a regular expression (using QRegularExpression).

text The string to search in

pattern The pattern to search for

index The index in text from which to start the search

options The options to use

matchedLength If there is a match, its length will be stored in this parameter

rmatch If there is a regular expression match (implies that the KFind::RegularExpression flag is set) and rmatch is not a nullptr the match result will be stored in this QRegularExpressionMatch object

Returns The index at which a match was found otherwise -1

This function was introduced in 5.70.

QDialog *KFind::findNextDialog(bool create = false)

Returns (or creates if create is true) the dialog that shows the "find next?" prompt. Usually you don't need to call this. One case where it can be useful, is when the user selects the "Find" menu item while a find operation is under way. In that case, the program may want to call setActiveWindow() on that dialog.

int KFind::index() const

Returns the current matching index (or -1). Same as the matchingIndex parameter passed to the textFound() signal. You usually don't need to use this, except maybe when updating the current data, so you need to call setData(newData, index()).

bool KFind::needData() const

Returns true if the application must supply a new text fragment It also means the last call returned "NoMatch". But by storing this here the application doesn't have to store it in a member variable (between calls to slotFindNext()).

int KFind::numMatches() const

Returns the number of matches found (i.e. the number of times the textFound() signal was emitted). If 0, can be used in a dialog box to tell the user "no match was found". The final dialog does so already, unless you used setDisplayFinalDialog(false).

long KFind::options() const

Return the current options.

Warning: this is usually the same value as the one passed to the constructor, but options might change _during_ the replace operation: e.g. the "All" button resets the PromptOnReplace flag.

See also setOptions() and KFind::Options.

[signal] void KFind::optionsChanged()

Emitted when the options have changed. This can happen e.g. with "Replace All", or if our 'find next' dialog gets a "find previous" one day.

QString KFind::pattern() const

Returns the pattern we're currently looking for

See also setPattern().

[virtual] void KFind::resetCounts()

Call this to reset the numMatches count (and the numReplacements count for a KReplace). Can be useful if reusing the same KReplace for different operations, or when restarting from the beginning of the document.

void KFind::setData(const QString &data, int startPos = -1)

Call this when needData returns true, before calling find().

data is the text fragment (line).

startPos if set, the index at which the search should start.

Usually startPos is only necessary for the very first call to setData, for the 'find in selection' feature. The default value of -1 means "process all the data", i.e. either 0 or data.length()-1 depending on FindBackwards.

void KFind::setData(int id, const QString &data, int startPos = -1)

Call this when needData returns true, before calling find(). The use of ID's is especially useful if you're using the FindIncremental option.

id the id of the text fragment.

data the text fragment (line).

startPos if set, the index at which the search should start. This is only necessary for the very first call to setData usually, for the 'find in selection' feature. A value of -1 (the default value) means "process all the data", i.e. either 0 or data.length()-1 depending on FindBackwards.

[virtual] void KFind::setOptions(long options)

Set new options. Usually this is used for setting or clearing the FindBackwards options.

See also options() and KFind::Options.

void KFind::setPattern(const QString &pattern)

Sets the pattern to look for

See also pattern().

[virtual] bool KFind::shouldRestart(bool forceAsking = false, bool showNumMatches = true) const

Returns true if we should restart the search from scratch. Can ask the user, or return false (if we already searched the whole document).

forceAsking set to true if the user modified the document during the search. In that case it makes sense to restart the search again.

showNumMatches set to true if the dialog should show the number of matches. Set to false if the application provides a "find previous" action, in which case the match count will be erroneous when hitting the end, and we could even be hitting the beginning of the document (so not all matches have even been seen).

[signal, since 5.81] void KFind::textFound(const QString &text, int matchingIndex, int matchedLength)

Connect to this signal to implement highlighting of found text during the find operation.

If you've set data with setData(id, text), use the textFoundAtId(int, int, int) signal.

WARNING: If you're using the FindIncremental option, the text argument passed by this signal is not necessarily the data last set through setData(), but can also be an earlier set data block.

text is the text that was found

matchingIndex is the index of the start of the matched text

matchedLength is the length of the matched text

This function was introduced in 5.81.

See also setData().

[signal, since 5.81] void KFind::textFoundAtId(int id, int matchingIndex, int matchedLength)

Connect to this signal to implement highlighting of found text during the find operation.

Use this signal if you've set your data with setData(id, text), otherwise use the textFound(text, matchingIndex, matchedLength) signal.

WARNING: If you're using the FindIncremental option, the id passed by this signal is not necessarily the id of the data last set through setData(), but can also be of an earlier set data block.

matchingIndex is the index of the start of the matched text

matchedLength is the length of the matched text

This function was introduced in 5.81.

See also setData().

[virtual] bool KFind::validateMatch(const QString &text, int index, int matchedlength)

Virtual method, which allows applications to add extra checks for validating a candidate match. It's only necessary to reimplement this if the find dialog extension has been used to provide additional criteria.

text The current text fragment

index The starting index where the candidate match was found

matchedlength The length of the candidate match

Returns true if the candidate matches.