examples/tools/customcompleter/textedit.cpp
changeset 0 1918ee327afb
child 3 41300fa6a67c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/examples/tools/customcompleter/textedit.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,174 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "textedit.h"
+#include <QCompleter>
+#include <QKeyEvent>
+#include <QAbstractItemView>
+#include <QtDebug>
+#include <QApplication>
+#include <QModelIndex>
+#include <QAbstractItemModel>
+#include <QScrollBar>
+
+//! [0]
+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));
+}
+//! [0]
+
+//! [1]
+TextEdit::~TextEdit()
+{
+}
+//! [1]
+
+//! [2]
+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(const QString&)),
+                     this, SLOT(insertCompletion(const QString&)));
+}
+//! [2]
+
+//! [3]
+QCompleter *TextEdit::completer() const
+{
+    return c;
+}
+//! [3]
+
+//! [4]
+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);
+}
+//! [4]
+
+//! [5]
+QString TextEdit::textUnderCursor() const
+{
+    QTextCursor tc = textCursor();
+    tc.select(QTextCursor::WordUnderCursor);
+    return tc.selectedText();
+}
+//! [5]
+
+//! [6]
+void TextEdit::focusInEvent(QFocusEvent *e)
+{
+    if (c)
+        c->setWidget(this);
+    QTextEdit::focusInEvent(e);
+}
+//! [6]
+
+//! [7]
+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) // dont process the shortcut when we have a completer
+        QTextEdit::keyPressEvent(e);
+//! [7]
+
+//! [8]
+    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!
+}
+//! [8]
+