Development/Tutorials/KWallet

Warning

This page needs a review and probably holds information that needs to be fixed.

Parts to be reviewed:

• Port to KF5
• Improve content

Abstract

A simple introduction for using the KWallet API, a secure storage framework.

Prerequisites: Basic KDE knowledge, C++.

Example

The API is fun and easy to use, and will guarantee you a long and stable life.

In KWallet, entries are organized in Folders (or think of it as categories), and in them there are binary data, maps, passwords and a catch-all unknown. Binary entries are application-specific arrays of bytes, maps should be known from QMaps, where a series of values are accessed by keys. Passwords are simply strings, and Unknown is for everything else.

dialog.cpp

 1 #include "dialog.h"
 2 
 3 #include <QLayout>
 4 #include <QLabel>
 5 #include <QPushButton>
 6 #include <QMap>
 7 #include <QVBoxLayout>
 8 #include <QSpacerItem>
 9 
10 Dialog::Dialog(QWidget *parent) :
11     QDialog(parent)
12 {
13     setLayout(new QVBoxLayout);
14     m_wallet = Wallet::openWallet(Wallet::NetworkWallet(),
15                                   winId(),
16                                   Wallet::Asynchronous);
17 
18     QLabel *explanation = new QLabel("<b>HELLO!</b><br/>"
19                                      "Please type in something to save in the wallet!<br/>"
20                                      "It will be saved in the form data folder, under <br/>"
21                                      "the entry <i>http://test.com/#form</i>.");
22     m_statusLabel = new QLabel("Opening wallet...", this);
23     m_statusLabel->setAlignment(Qt::AlignCenter);
24     m_keyInput = new QLineEdit(this);
25     m_valueInput = new QLineEdit(this);
26     m_launchButton = new QPushButton("Save!", this);
27     m_launchButton->setDisabled(true);
28 
29     layout()->addWidget(explanation);
30     qobject_cast<QVBoxLayout*>(layout())->addStretch();
31     layout()->addWidget(m_statusLabel);
32     layout()->addWidget(new QLabel("Key:", this));
33     layout()->addWidget(m_keyInput);
34     layout()->addWidget(new QLabel("Value:", this));
35     layout()->addWidget(m_valueInput);
36     layout()->addWidget(m_launchButton);
37 
38     connect(m_launchButton, SIGNAL(clicked()), SLOT(doSave()));
39     connect(m_wallet, SIGNAL(walletOpened(bool)), SLOT(walletOpened(bool)));
40     setMinimumSize(500, 200);
41 }
42 
43 void Dialog::walletOpened(bool ok)
44 {
45 
46     if (ok &&
47         (m_wallet->hasFolder(KWallet::Wallet::FormDataFolder()) ||
48         m_wallet->createFolder(KWallet::Wallet::FormDataFolder())) &&
49         m_wallet->setFolder(KWallet::Wallet::FormDataFolder())) {
50         m_launchButton->setDisabled(false);
51         m_statusLabel->setText("Idle.");
52     } else
53         m_statusLabel->setText("Error opening wallet!");
54 
55 }
56 
57 void Dialog::doSave()
58 {
59     if (m_keyInput->text().isEmpty() || m_valueInput->text().isEmpty()) {
60         m_statusLabel->setText("Empty field!");
61         return;
62     }
63 
64     m_launchButton->setDisabled(true);
65 
66     m_statusLabel->setText("Saving ...");
67 
68     QMap<QString, QString> map;
69     map[m_keyInput->text()] = m_valueInput->text();
70     if (m_wallet->writeMap("http://test.com/#form", map)) m_statusLabel->setText("Something went wrong!");
71     else {
72         m_statusLabel->setText("Saved!");
73         m_keyInput->clear();
74         m_valueInput->clear();
75     }
76     m_launchButton->setDisabled(false);
77 }

dialog.h

 1 #ifndef DIALOG_H
 2 #define DIALOG_H
 3 
 4 #include <QDialog>
 5 #include <QLabel>
 6 #include <QLineEdit>
 7 #include <KWallet/Wallet>
 8 
 9 using KWallet::Wallet;
10 
11 class Dialog : public QDialog
12 {
13 Q_OBJECT
14 public:
15     Dialog(QWidget *parent = 0);
16 
17 private slots:
18     void doSave();
19     void walletOpened(bool ok);
20 
21 private:
22     Wallet *m_wallet;
23     QLineEdit *m_keyInput;
24     QLineEdit *m_valueInput;
25     QLabel *m_statusLabel;
26     QPushButton *m_launchButton;
27 };
28 
29 #endif // DIALOG_H

main.cpp

 1 #include "dialog.h"
 2 
 3 #include <KAboutData>
 4 #include <KApplication>
 5 #include <KCmdLineArgs>
 6 
 7 static KAboutData about(
 8     "KWalletDemoApplication",
 9     "",
10     ki18n("KWalletDemoApplication"),
11     "1.0",
12     ki18n("Demonstrates basic KWallet usage."),
13     KAboutData::License_LGPL,
14     ki18n("(C) 2010 Martin Sandsmark"),
15     KLocalizedString(),
16     "http://www.mts.ms/");
17 
18 int main(int argc, char *argv[])
19 {
20     about.addAuthor(ki18n("Martin Sandsmark"), ki18n("Maintainer"), "martin.sandsmark@kde.org", "http://iskrembilen.com/");
21 
22     KCmdLineArgs::init(argc, argv, &about);
23     KApplication app;
24 
25     Dialog dialog;
26     dialog.show();
27     return app.exec();
28 }

CMakeLists.txt

 1 project(Importer)
 2 
 3 find_package(KDE4 REQUIRED)
 4 add_definitions(${QT_DEFINITIONS} ${KDE4_DEFINITIONS})
 5 include(KDE4Defaults)
 6 include(MacroLibrary)
 7 include_directories(${KDE4_INCLUDES} ${KDE4_INCLUDE_DIR} ${QT_INCLUDES})
 8 
 9 set(SRCS main.cpp dialog.cpp)
10 
11 kde4_add_executable(kwallet-demo ${SRCS})
12 target_link_libraries(kwallet-demo ${KDE4_KDECORE_LIBS} ${KDE4_KPARTS_LIBS} ${KDE4_KDEUI_LIBS})
13 install(TARGETS kwallet-demo ${INSTALL_TARGETS_DEFAULT_ARGS})