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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]
62TextEdit::TextEdit(QWidget *parent)
63 : QTextEdit(parent)
64{
65 setPlainText(tr(s: "This TextEdit provides autocompletions for words that have more than"
66 " 3 characters. You can trigger autocompletion using ") +
67 QKeySequence("Ctrl+E").toString(format: QKeySequence::NativeText));
68}
69//! [0]
70
71//! [1]
72TextEdit::~TextEdit()
73{
74}
75//! [1]
76
77//! [2]
78void TextEdit::setCompleter(QCompleter *completer)
79{
80 if (c)
81 c->disconnect(receiver: 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(sender: c, signal: QOverload<const QString &>::of(ptr: &QCompleter::activated),
92 receiver: this, slot: &TextEdit::insertCompletion);
93}
94//! [2]
95
96//! [3]
97QCompleter *TextEdit::completer() const
98{
99 return c;
100}
101//! [3]
102
103//! [4]
104void 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(op: QTextCursor::Left);
111 tc.movePosition(op: QTextCursor::EndOfWord);
112 tc.insertText(text: completion.right(n: extra));
113 setTextCursor(tc);
114}
115//! [4]
116
117//! [5]
118QString TextEdit::textUnderCursor() const
119{
120 QTextCursor tc = textCursor();
121 tc.select(selection: QTextCursor::WordUnderCursor);
122 return tc.selectedText();
123}
124//! [5]
125
126//! [6]
127void TextEdit::focusInEvent(QFocusEvent *e)
128{
129 if (c)
130 c->setWidget(this);
131 QTextEdit::focusInEvent(e);
132}
133//! [6]
134
135//! [7]
136void 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(flag: 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(flag: Qt::ControlModifier) ||
160 e->modifiers().testFlag(flag: 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(s: e->text().right(n: 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(row: 0, column: 0));
177 }
178 QRect cr = cursorRect();
179 cr.setWidth(c->popup()->sizeHintForColumn(column: 0)
180 + c->popup()->verticalScrollBar()->sizeHint().width());
181 c->complete(rect: cr); // popup it up!
182}
183//! [8]
184
185

source code of qtbase/examples/widgets/tools/customcompleter/textedit.cpp