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50
51#include "echowindow.h"
52
53#include <QCoreApplication>
54#include <QDir>
55#include <QLabel>
56#include <QLayout>
57#include <QLineEdit>
58#include <QMessageBox>
59#include <QPluginLoader>
60#include <QPushButton>
61
62//! [0]
63EchoWindow::EchoWindow()
64{
65 createGUI();
66 setLayout(layout);
67 setWindowTitle("Echo Plugin Example");
68
69 if (!loadPlugin()) {
70 QMessageBox::information(parent: this, title: "Error", text: "Could not load the plugin");
71 lineEdit->setEnabled(false);
72 button->setEnabled(false);
73 }
74}
75//! [0]
76
77//! [1]
78void EchoWindow::sendEcho()
79{
80 QString text = echoInterface->echo(message: lineEdit->text());
81 label->setText(text);
82}
83//! [1]
84
85//! [2]
86void EchoWindow::createGUI()
87{
88 lineEdit = new QLineEdit;
89 label = new QLabel;
90 label->setFrameStyle(QFrame::Box | QFrame::Plain);
91 button = new QPushButton(tr(s: "Send Message"));
92
93 connect(sender: lineEdit, signal: &QLineEdit::editingFinished,
94 receiver: this, slot: &EchoWindow::sendEcho);
95 connect(sender: button, signal: &QPushButton::clicked,
96 receiver: this, slot: &EchoWindow::sendEcho);
97
98 layout = new QGridLayout;
99 layout->addWidget(new QLabel(tr(s: "Message:")), row: 0, column: 0);
100 layout->addWidget(lineEdit, row: 0, column: 1);
101 layout->addWidget(new QLabel(tr(s: "Answer:")), row: 1, column: 0);
102 layout->addWidget(label, row: 1, column: 1);
103 layout->addWidget(button, row: 2, column: 1, Qt::AlignRight);
104 layout->setSizeConstraint(QLayout::SetFixedSize);
105}
106//! [2]
107
108//! [3]
109bool EchoWindow::loadPlugin()
110{
111 QDir pluginsDir(QCoreApplication::applicationDirPath());
112#if defined(Q_OS_WIN)
113 if (pluginsDir.dirName().toLower() == "debug" || pluginsDir.dirName().toLower() == "release")
114 pluginsDir.cdUp();
115#elif defined(Q_OS_MAC)
116 if (pluginsDir.dirName() == "MacOS") {
117 pluginsDir.cdUp();
118 pluginsDir.cdUp();
119 pluginsDir.cdUp();
120 }
121#endif
122 pluginsDir.cd(dirName: "plugins");
123 const QStringList entries = pluginsDir.entryList(filters: QDir::Files);
124 for (const QString &fileName : entries) {
125 QPluginLoader pluginLoader(pluginsDir.absoluteFilePath(fileName));
126 QObject *plugin = pluginLoader.instance();
127 if (plugin) {
128 echoInterface = qobject_cast<EchoInterface *>(object: plugin);
129 if (echoInterface)
130 return true;
131 pluginLoader.unload();
132 }
133 }
134
135 return false;
136}
137//! [3]
138

source code of qtbase/examples/widgets/tools/echoplugin/echowindow/echowindow.cpp