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50
51#include "googlesuggest.h"
52
53//! [1]
54const QString gsuggestUrl(QStringLiteral("http://google.com/complete/search?output=toolbar&q=%1"));
55//! [1]
56
57//! [2]
58GSuggestCompletion::GSuggestCompletion(QLineEdit *parent): QObject(parent), editor(parent)
59{
60 popup = new QTreeWidget;
61 popup->setWindowFlags(Qt::Popup);
62 popup->setFocusPolicy(Qt::NoFocus);
63 popup->setFocusProxy(parent);
64 popup->setMouseTracking(true);
65
66 popup->setColumnCount(1);
67 popup->setUniformRowHeights(true);
68 popup->setRootIsDecorated(false);
69 popup->setEditTriggers(QTreeWidget::NoEditTriggers);
70 popup->setSelectionBehavior(QTreeWidget::SelectRows);
71 popup->setFrameStyle(QFrame::Box | QFrame::Plain);
72 popup->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
73 popup->header()->hide();
74
75 popup->installEventFilter(filterObj: this);
76
77 connect(sender: popup, signal: &QTreeWidget::itemClicked,
78 receiver: this, slot: &GSuggestCompletion::doneCompletion);
79
80 timer.setSingleShot(true);
81 timer.setInterval(500);
82 connect(sender: &timer, signal: &QTimer::timeout,
83 receiver: this, slot: &GSuggestCompletion::autoSuggest);
84 connect(sender: editor, signal: &QLineEdit::textEdited,
85 receiver: &timer, slot: QOverload<>::of(ptr: &QTimer::start));
86
87 connect(sender: &networkManager, signal: &QNetworkAccessManager::finished,
88 receiver: this, slot: &GSuggestCompletion::handleNetworkData);
89
90}
91//! [2]
92
93//! [3]
94GSuggestCompletion::~GSuggestCompletion()
95{
96 delete popup;
97}
98//! [3]
99
100//! [4]
101bool GSuggestCompletion::eventFilter(QObject *obj, QEvent *ev)
102{
103 if (obj != popup)
104 return false;
105
106 if (ev->type() == QEvent::MouseButtonPress) {
107 popup->hide();
108 editor->setFocus();
109 return true;
110 }
111
112 if (ev->type() == QEvent::KeyPress) {
113 bool consumed = false;
114 int key = static_cast<QKeyEvent*>(ev)->key();
115 switch (key) {
116 case Qt::Key_Enter:
117 case Qt::Key_Return:
118 doneCompletion();
119 consumed = true;
120 break;
121
122 case Qt::Key_Escape:
123 editor->setFocus();
124 popup->hide();
125 consumed = true;
126 break;
127
128 case Qt::Key_Up:
129 case Qt::Key_Down:
130 case Qt::Key_Home:
131 case Qt::Key_End:
132 case Qt::Key_PageUp:
133 case Qt::Key_PageDown:
134 break;
135
136 default:
137 editor->setFocus();
138 editor->event(ev);
139 popup->hide();
140 break;
141 }
142
143 return consumed;
144 }
145
146 return false;
147}
148//! [4]
149
150//! [5]
151void GSuggestCompletion::showCompletion(const QVector<QString> &choices)
152{
153 if (choices.isEmpty())
154 return;
155
156 const QPalette &pal = editor->palette();
157 QColor color = pal.color(cg: QPalette::Disabled, cr: QPalette::WindowText);
158
159 popup->setUpdatesEnabled(false);
160 popup->clear();
161
162 for (const auto &choice : choices) {
163 auto item = new QTreeWidgetItem(popup);
164 item->setText(column: 0, atext: choice);
165 item->setForeground(column: 0, brush: color);
166 }
167
168 popup->setCurrentItem(popup->topLevelItem(index: 0));
169 popup->resizeColumnToContents(column: 0);
170 popup->setUpdatesEnabled(true);
171
172 popup->move(editor->mapToGlobal(QPoint(0, editor->height())));
173 popup->setFocus();
174 popup->show();
175}
176//! [5]
177
178//! [6]
179void GSuggestCompletion::doneCompletion()
180{
181 timer.stop();
182 popup->hide();
183 editor->setFocus();
184 QTreeWidgetItem *item = popup->currentItem();
185 if (item) {
186 editor->setText(item->text(column: 0));
187 QMetaObject::invokeMethod(obj: editor, member: "returnPressed");
188 }
189}
190//! [6]
191
192//! [7]
193void GSuggestCompletion::autoSuggest()
194{
195 QString str = editor->text();
196 QString url = gsuggestUrl.arg(a: str);
197 networkManager.get(request: QNetworkRequest(url));
198}
199//! [7]
200
201//! [8]
202void GSuggestCompletion::preventSuggest()
203{
204 timer.stop();
205}
206//! [8]
207
208//! [9]
209void GSuggestCompletion::handleNetworkData(QNetworkReply *networkReply)
210{
211 QUrl url = networkReply->url();
212 if (networkReply->error() == QNetworkReply::NoError) {
213 QVector<QString> choices;
214
215 QByteArray response(networkReply->readAll());
216 QXmlStreamReader xml(response);
217 while (!xml.atEnd()) {
218 xml.readNext();
219 if (xml.tokenType() == QXmlStreamReader::StartElement)
220 if (xml.name() == "suggestion") {
221 QStringRef str = xml.attributes().value(qualifiedName: "data");
222 choices << str.toString();
223 }
224 }
225
226 showCompletion(choices);
227 }
228
229 networkReply->deleteLater();
230}
231//! [9]
232

source code of qtbase/examples/network/googlesuggest/googlesuggest.cpp