clang-tidy, qt: Fix modernize-use-default-member-init in headers

See https://clang.llvm.org/extra/clang-tidy/checks/modernize/use-default-member-init.html

Author: hebasto

src/qt/addressbookpage.cpp

@@ -64,7 +64,6 @@ class AddressBookSortFilterProxyModel final : public QSortFilterProxyModel
 AddressBookPage::AddressBookPage(const PlatformStyle *platformStyle, Mode _mode, Tabs _tab, QWidget *parent) :
     QDialog(parent, GUIUtil::dialog_flags),
     ui(new Ui::AddressBookPage),
-    model(nullptr),
     mode(_mode),
     tab(_tab)
 {

src/qt/addressbookpage.h

@@ -49,7 +49,7 @@ public Q_SLOTS:
 
 private:
     Ui::AddressBookPage *ui;
-    AddressTableModel *model;
+    AddressTableModel* model{nullptr};
     Mode mode;
     Tabs tab;
     QString returnValue;

src/qt/askpassphrasedialog.cpp

@@ -23,8 +23,6 @@ AskPassphraseDialog::AskPassphraseDialog(Mode _mode, QWidget *parent, SecureStri
     QDialog(parent, GUIUtil::dialog_flags),
     ui(new Ui::AskPassphraseDialog),
     mode(_mode),
-    model(nullptr),
-    fCapsLock(false),
     m_passphrase_out(passphrase_out)
 {
     ui->setupUi(this);

src/qt/askpassphrasedialog.h

@@ -38,8 +38,8 @@ class AskPassphraseDialog : public QDialog
 private:
     Ui::AskPassphraseDialog *ui;
     Mode mode;
-    WalletModel *model;
-    bool fCapsLock;
+    WalletModel* model{nullptr};
+    bool fCapsLock{false};
     SecureString* m_passphrase_out;
 
 private Q_SLOTS:

src/qt/bitcoin.cpp

@@ -228,14 +228,8 @@ void DebugMessageHandler(QtMsgType type, const QMessageLogContext& context, cons
 static int qt_argc = 1;
 static const char* qt_argv = "bitcoin-qt";
 
-BitcoinApplication::BitcoinApplication():
-    QApplication(qt_argc, const_cast<char **>(&qt_argv)),
-    optionsModel(nullptr),
-    clientModel(nullptr),
-    window(nullptr),
-    pollShutdownTimer(nullptr),
-    returnValue(0),
-    platformStyle(nullptr)
+BitcoinApplication::BitcoinApplication()
+    : QApplication(qt_argc, const_cast<char**>(&qt_argv))
 {
     // Qt runs setlocale(LC_ALL, "") on initialization.
     RegisterMetaTypes();

src/qt/bitcoin.h

@@ -97,16 +97,16 @@ public Q_SLOTS:
 
 private:
     std::optional<InitExecutor> m_executor;
-    OptionsModel *optionsModel;
-    ClientModel *clientModel;
-    BitcoinGUI *window;
-    QTimer *pollShutdownTimer;
+    OptionsModel* optionsModel{nullptr};
+    ClientModel* clientModel{nullptr};
+    BitcoinGUI* window{nullptr};
+    QTimer* pollShutdownTimer{nullptr};
 #ifdef ENABLE_WALLET
     PaymentServer* paymentServer{nullptr};
     WalletController* m_wallet_controller{nullptr};
 #endif
-    int returnValue;
-    const PlatformStyle *platformStyle;
+    int returnValue{0};
+    const PlatformStyle* platformStyle{nullptr};
     std::unique_ptr<QWidget> shutdownWindow;
     SplashScreen* m_splash = nullptr;
     std::unique_ptr<interfaces::Node> m_node;

src/qt/bitcoinamountfield.cpp

@@ -217,9 +217,8 @@ class AmountSpinBox: public QAbstractSpinBox
 
 #include <qt/bitcoinamountfield.moc>
 
-BitcoinAmountField::BitcoinAmountField(QWidget *parent) :
-    QWidget(parent),
-    amount(nullptr)
+BitcoinAmountField::BitcoinAmountField(QWidget* parent)
+    : QWidget(parent)
 {
     amount = new AmountSpinBox(this);
     amount->setLocale(QLocale::c());

src/qt/bitcoinamountfield.h

@@ -74,7 +74,7 @@ class BitcoinAmountField: public QWidget
     bool eventFilter(QObject *object, QEvent *event) override;
 
 private:
-    AmountSpinBox *amount;
+    AmountSpinBox* amount{nullptr};
     QValueComboBox *unit;
 
 private Q_SLOTS:

src/qt/bitcoingui.cpp

@@ -1541,10 +1541,8 @@ bool BitcoinGUI::isPrivacyModeActivated() const
     return m_mask_values_action->isChecked();
 }
 
-UnitDisplayStatusBarControl::UnitDisplayStatusBarControl(const PlatformStyle *platformStyle)
-    : optionsModel(nullptr),
-      menu(nullptr),
-      m_platform_style{platformStyle}
+UnitDisplayStatusBarControl::UnitDisplayStatusBarControl(const PlatformStyle* platformStyle)
+    : m_platform_style{platformStyle}
 {
     createContextMenu();
     setToolTip(tr("Unit to show amounts in. Click to select another unit."));

src/qt/bitcoingui.h

@@ -333,8 +333,8 @@ class UnitDisplayStatusBarControl : public QLabel
     void changeEvent(QEvent* e) override;
 
 private:
-    OptionsModel *optionsModel;
-    QMenu* menu;
+    OptionsModel* optionsModel{nullptr};
+    QMenu* menu{nullptr};
     const PlatformStyle* m_platform_style;
 
     /** Shows context menu with Display Unit options by the mouse coordinates */