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50
51 #include "textedit.h"
52 #include <QCompleter>
53 #include <QKeyEvent>
54 #include <QAbstractItemView>
55 #include <QtDebug>
56 #include <QApplication>
57 #include <QModelIndex>
58 #include <QAbstractItemModel>
59 #include <QScrollBar>
60
61 //! [0]
TextEdit(QWidget * parent)62 TextEdit::TextEdit(QWidget *parent)
63 : QTextEdit(parent)
64 {
65 setPlainText(tr("This TextEdit provides autocompletions for words that have more than"
66 " 3 characters. You can trigger autocompletion using ") +
67 QKeySequence("Ctrl+E").toString(QKeySequence::NativeText));
68 }
69 //! [0]
70
71 //! [1]
~TextEdit()72 TextEdit::~TextEdit()
73 {
74 }
75 //! [1]
76
77 //! [2]
setCompleter(QCompleter * completer)78 void TextEdit::setCompleter(QCompleter *completer)
79 {
80 if (c)
81 c->disconnect(this);
82
83 c = completer;
84
85 if (!c)
86 return;
87
88 c->setWidget(this);
89 c->setCompletionMode(QCompleter::PopupCompletion);
90 c->setCaseSensitivity(Qt::CaseInsensitive);
91 QObject::connect(c, QOverload<const QString &>::of(&QCompleter::activated),
92 this, &TextEdit::insertCompletion);
93 }
94 //! [2]
95
96 //! [3]
completer() const97 QCompleter *TextEdit::completer() const
98 {
99 return c;
100 }
101 //! [3]
102
103 //! [4]
insertCompletion(const QString & completion)104 void TextEdit::insertCompletion(const QString &completion)
105 {
106 if (c->widget() != this)
107 return;
108 QTextCursor tc = textCursor();
109 int extra = completion.length() - c->completionPrefix().length();
110 tc.movePosition(QTextCursor::Left);
111 tc.movePosition(QTextCursor::EndOfWord);
112 tc.insertText(completion.right(extra));
113 setTextCursor(tc);
114 }
115 //! [4]
116
117 //! [5]
textUnderCursor() const118 QString TextEdit::textUnderCursor() const
119 {
120 QTextCursor tc = textCursor();
121 tc.select(QTextCursor::WordUnderCursor);
122 return tc.selectedText();
123 }
124 //! [5]
125
126 //! [6]
focusInEvent(QFocusEvent * e)127 void TextEdit::focusInEvent(QFocusEvent *e)
128 {
129 if (c)
130 c->setWidget(this);
131 QTextEdit::focusInEvent(e);
132 }
133 //! [6]
134
135 //! [7]
keyPressEvent(QKeyEvent * e)136 void TextEdit::keyPressEvent(QKeyEvent *e)
137 {
138 if (c && c->popup()->isVisible()) {
139 // The following keys are forwarded by the completer to the widget
140 switch (e->key()) {
141 case Qt::Key_Enter:
142 case Qt::Key_Return:
143 case Qt::Key_Escape:
144 case Qt::Key_Tab:
145 case Qt::Key_Backtab:
146 e->ignore();
147 return; // let the completer do default behavior
148 default:
149 break;
150 }
151 }
152
153 const bool isShortcut = (e->modifiers().testFlag(Qt::ControlModifier) && e->key() == Qt::Key_E); // CTRL+E
154 if (!c || !isShortcut) // do not process the shortcut when we have a completer
155 QTextEdit::keyPressEvent(e);
156 //! [7]
157
158 //! [8]
159 const bool ctrlOrShift = e->modifiers().testFlag(Qt::ControlModifier) ||
160 e->modifiers().testFlag(Qt::ShiftModifier);
161 if (!c || (ctrlOrShift && e->text().isEmpty()))
162 return;
163
164 static QString eow("~!@#$%^&*()_+{}|:\"<>?,./;'[]\\-="); // end of word
165 const bool hasModifier = (e->modifiers() != Qt::NoModifier) && !ctrlOrShift;
166 QString completionPrefix = textUnderCursor();
167
168 if (!isShortcut && (hasModifier || e->text().isEmpty()|| completionPrefix.length() < 3
169 || eow.contains(e->text().right(1)))) {
170 c->popup()->hide();
171 return;
172 }
173
174 if (completionPrefix != c->completionPrefix()) {
175 c->setCompletionPrefix(completionPrefix);
176 c->popup()->setCurrentIndex(c->completionModel()->index(0, 0));
177 }
178 QRect cr = cursorRect();
179 cr.setWidth(c->popup()->sizeHintForColumn(0)
180 + c->popup()->verticalScrollBar()->sizeHint().width());
181 c->complete(cr); // popup it up!
182 }
183 //! [8]
184
185