textedit.cpp Example File

tools/customcompleter/textedit.cpp
/**************************************************************************** ** ** Copyright (C) 2016 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the examples of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** BSD License Usage ** Alternatively, you may use this file under the terms of the BSD license ** as follows: ** ** "Redistribution and use in source and binary forms, with or without ** modification, are permitted provided that the following conditions are ** met: ** * Redistributions of source code must retain the above copyright ** notice, this list of conditions and the following disclaimer. ** * Redistributions in binary form must reproduce the above copyright ** notice, this list of conditions and the following disclaimer in ** the documentation and/or other materials provided with the ** distribution. ** * Neither the name of The Qt Company Ltd nor the names of its ** contributors may be used to endorse or promote products derived ** from this software without specific prior written permission. ** ** ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." ** ** $QT_END_LICENSE$ ** ****************************************************************************/
#include "textedit.h" #include <QCompleter> #include <QKeyEvent> #include <QAbstractItemView> #include <QtDebug> #include <QApplication> #include <QModelIndex> #include <QAbstractItemModel> #include <QScrollBar> TextEdit::TextEdit(QWidget *parent) : QTextEdit(parent), c(0) { setPlainText(tr("This TextEdit provides autocompletions for words that have more than" " 3 characters. You can trigger autocompletion using ") + QKeySequence("Ctrl+E").toString(QKeySequence::NativeText)); } TextEdit::~TextEdit() { } void TextEdit::setCompleter(QCompleter *completer) { if (c) QObject::disconnect(c, 0, this, 0); c = completer; if (!c) return; c->setWidget(this); c->setCompletionMode(QCompleter::PopupCompletion); c->setCaseSensitivity(Qt::CaseInsensitive); QObject::connect(c, SIGNAL(activated(QString)), this, SLOT(insertCompletion(QString))); } QCompleter *TextEdit::completer() const { return c; } void TextEdit::insertCompletion(const QString& completion) { if (c->widget() != this) return; QTextCursor tc = textCursor(); int extra = completion.length() - c->completionPrefix().length(); tc.movePosition(QTextCursor::Left); tc.movePosition(QTextCursor::EndOfWord); tc.insertText(completion.right(extra)); setTextCursor(tc); } QString TextEdit::textUnderCursor() const { QTextCursor tc = textCursor(); tc.select(QTextCursor::WordUnderCursor); return tc.selectedText(); } void TextEdit::focusInEvent(QFocusEvent *e) { if (c) c->setWidget(this); QTextEdit::focusInEvent(e); } void TextEdit::keyPressEvent(QKeyEvent *e) { if (c && c->popup()->isVisible()) { // The following keys are forwarded by the completer to the widget switch (e->key()) { case Qt::Key_Enter: case Qt::Key_Return: case Qt::Key_Escape: case Qt::Key_Tab: case Qt::Key_Backtab: e->ignore(); return; // let the completer do default behavior default: break; } } bool isShortcut = ((e->modifiers() & Qt::ControlModifier) && e->key() == Qt::Key_E); // CTRL+E if (!c || !isShortcut) // do not process the shortcut when we have a completer QTextEdit::keyPressEvent(e); const bool ctrlOrShift = e->modifiers() & (Qt::ControlModifier | Qt::ShiftModifier); if (!c || (ctrlOrShift && e->text().isEmpty())) return; static QString eow("~!@#$%^&*()_+{}|:\"<>?,./;'[]\\-="); // end of word bool hasModifier = (e->modifiers() != Qt::NoModifier) && !ctrlOrShift; QString completionPrefix = textUnderCursor(); if (!isShortcut && (hasModifier || e->text().isEmpty()|| completionPrefix.length() < 3 || eow.contains(e->text().right(1)))) { c->popup()->hide(); return; } if (completionPrefix != c->completionPrefix()) { c->setCompletionPrefix(completionPrefix); c->popup()->setCurrentIndex(c->completionModel()->index(0, 0)); } QRect cr = cursorRect(); cr.setWidth(c->popup()->sizeHintForColumn(0) + c->popup()->verticalScrollBar()->sizeHint().width()); c->complete(cr); // popup it up! }