Merge #13791: gui: Reject dialogs if key escape is pressed

7bf22bf gui: Reject options dialog when key escape is pressed (João Barbosa)
4a43306 gui: Reject edit address dialog when key escape is pressed (João Barbosa)
f7a5531 gui: Add GUIUtil::ItemDelegate with keyEscapePressed signal (João Barbosa)

Pull request description:

  Currently `EditAddressDialog` and `OptionsDialog` don't close when the escape key is pressed. The `QDataWidgetMapper` instances prevents closing the dialogs because the escape key is used to reset the widgets values. More details and workarounds in https://stackoverflow.com/a/51487847 and http://qtramblings.blogspot.com/2010/10/qdatawidgetmapper-annoyances.html.

  The adopted solution is different from the above references. It turns out that `QDataWidgetMapper::setItemDelegate` sets the event filter for all mapped widgets. So in this PR the mapper's delegate are changed to a custom `GUIUtil::ItemDelegate` that offers the signal `keyEscapePressed`, which is connected to the `QDialog::reject` slot.

  Note that the installed event filter lets all events pass, so the current behaviour isn't changed, meaning that widgets values are reset in addition to closing the dialog.

Tree-SHA512: 9c961d488480b4ccc3880a11a8f1824b65f77570ee8918c7302c62775a1a73e52ae988a31a55ffff87b4170ddbecf833c2f09b66095c00eb6854a4d43f030f1f

Author: laanwj

src/qt/editaddressdialog.cpp

@@ -39,6 +39,10 @@ EditAddressDialog::EditAddressDialog(Mode _mode, QWidget *parent) :
 
     mapper = new QDataWidgetMapper(this);
     mapper->setSubmitPolicy(QDataWidgetMapper::ManualSubmit);
+
+    GUIUtil::ItemDelegate* delegate = new GUIUtil::ItemDelegate(mapper);
+    connect(delegate, &GUIUtil::ItemDelegate::keyEscapePressed, this, &EditAddressDialog::reject);
+    mapper->setItemDelegate(delegate);
 }
 
 EditAddressDialog::~EditAddressDialog()

src/qt/guiutil.cpp

@@ -49,6 +49,7 @@
 #include <QDoubleValidator>
 #include <QFileDialog>
 #include <QFont>
+#include <QKeyEvent>
 #include <QLineEdit>
 #include <QSettings>
 #include <QTextDocument> // for Qt::mightBeRichText
@@ -927,4 +928,14 @@ void ClickableProgressBar::mouseReleaseEvent(QMouseEvent *event)
     Q_EMIT clicked(event->pos());
 }
 
+bool ItemDelegate::eventFilter(QObject *object, QEvent *event)
+{
+    if (event->type() == QEvent::KeyPress) {
+        if (static_cast<QKeyEvent*>(event)->key() == Qt::Key_Escape) {
+            Q_EMIT keyEscapePressed();
+        }
+    }
+    return QItemDelegate::eventFilter(object, event);
+}
+
 } // namespace GUIUtil

src/qt/guiutil.h

@@ -10,6 +10,7 @@
 
 #include <QEvent>
 #include <QHeaderView>
+#include <QItemDelegate>
 #include <QMessageBox>
 #include <QObject>
 #include <QProgressBar>
@@ -232,6 +233,18 @@ namespace GUIUtil
 
     typedef ClickableProgressBar ProgressBar;
 
+    class ItemDelegate : public QItemDelegate
+    {
+        Q_OBJECT
+    public:
+        ItemDelegate(QObject* parent) : QItemDelegate(parent) {}
+
+    Q_SIGNALS:
+        void keyEscapePressed();
+
+    private:
+        bool eventFilter(QObject *object, QEvent *event);
+    };
 } // namespace GUIUtil
 
 #endif // BITCOIN_QT_GUIUTIL_H

src/qt/optionsdialog.cpp

@@ -115,6 +115,10 @@ OptionsDialog::OptionsDialog(QWidget *parent, bool enableWallet) :
     mapper->setSubmitPolicy(QDataWidgetMapper::ManualSubmit);
     mapper->setOrientation(Qt::Vertical);
 
+    GUIUtil::ItemDelegate* delegate = new GUIUtil::ItemDelegate(mapper);
+    connect(delegate, &GUIUtil::ItemDelegate::keyEscapePressed, this, &OptionsDialog::reject);
+    mapper->setItemDelegate(delegate);
+
     /* setup/change UI elements when proxy IPs are invalid/valid */
     ui->proxyIp->setCheckValidator(new ProxyAddressValidator(parent));
     ui->proxyIpTor->setCheckValidator(new ProxyAddressValidator(parent));