Make the Qt ComboBox behave in a Better Way

So, the ComboBox is a beast, and when used on a Delegate
it's very hard to get things right, wich is a pitty, because
I overly like qt. So:

1 - Combobox needs to show the popup when user press ↓ and ↑ keys
2 - Combobox needs to select when user press enter, not twice.
3 - Combobox neesds to select when user selects from the mouse, not
pressing enter after.
4 - Combobox needs to not mess with stuff when moving around.

Everything that I listed there works on a non-delegate combobox,
but for some reason, a delegate missed those, so I reimplemented
all. not nice, but now we have a code that will work, I hope.
*fingers crossed*

Signed-off-by: Tomaz Canabrava <tcanabrava@kde.org>

qt-ui/modeldelegates.cpp

@@ -80,6 +80,7 @@ struct CurrSelected{
 	int currRow;
 	QString activeText;
 	QAbstractItemModel *model;
+	bool ignoreSelection;
 } currCombo;
 
 QWidget* ComboBoxDelegate::createEditor(QWidget* parent, const QStyleOptionViewItem& option, const QModelIndex& index) const
@@ -90,9 +91,11 @@ QWidget* ComboBoxDelegate::createEditor(QWidget* parent, const QStyleOptionViewI
 	comboDelegate->setAutoCompletion(true);
 	comboDelegate->setAutoCompletionCaseSensitivity(Qt::CaseInsensitive);
 	comboDelegate->completer()->setCompletionMode(QCompleter::PopupCompletion);
+	comboDelegate->view()->setEditTriggers(QAbstractItemView::AllEditTriggers);
 	comboDelegate->lineEdit()->installEventFilter( const_cast<QObject*>(qobject_cast<const QObject*>(this)));
 	comboDelegate->view()->installEventFilter( const_cast<QObject*>(qobject_cast<const QObject*>(this)));
 	connect(comboDelegate, SIGNAL(highlighted(QString)), this, SLOT(testActivation(QString)));
+	connect(comboDelegate, SIGNAL(activated(QString)), this, SLOT(fakeActivation()));
 	currCombo.comboEditor = comboDelegate;
 	currCombo.currRow = index.row();
 	currCombo.model = const_cast<QAbstractItemModel*>(index.model());
@@ -105,6 +108,23 @@ void ComboBoxDelegate::testActivation(const QString& s)
 	setModelData(currCombo.comboEditor, currCombo.model, QModelIndex());
 }
 
+// HACK, send a fake event so Qt thinks we hit 'enter' on the line edit.
+void ComboBoxDelegate::fakeActivation(){
+	/* this test is needed because as soon as I show the selector,
+	 * the first item gots selected, this sending an activated signal,
+	 * calling this fakeActivation code and setting as the current,
+	 * thig that we don't want. so, let's just set the ignoreSelection
+	 * to false and be happy, because the next activation  ( by click
+	 * or keypress) is real.
+	 */
+	if(currCombo.ignoreSelection){
+		currCombo.ignoreSelection = false;
+		return;
+	}
+	QKeyEvent ev(QEvent::KeyPress, Qt::Key_Return, Qt::NoModifier);
+	QStyledItemDelegate::eventFilter(currCombo.comboEditor, &ev);
+}
+
 bool ComboBoxDelegate::eventFilter(QObject* object, QEvent* event)
 {
 	// Reacts on Key_UP and Key_DOWN to show the QComboBox - list of choices.
@@ -112,6 +132,7 @@ bool ComboBoxDelegate::eventFilter(QObject* object, QEvent* event)
 		if (object == currCombo.comboEditor){ // the 'LineEdit' part
 			QKeyEvent *ev = static_cast<QKeyEvent*>(event);
 			if(ev->key() == Qt::Key_Up || ev->key() == Qt::Key_Down){
+				currCombo.ignoreSelection = true;
 				currCombo.comboEditor->showPopup();
 			}
 		}

qt-ui/modeldelegates.h

@@ -24,6 +24,8 @@ public:
     virtual bool eventFilter(QObject* object, QEvent* event);
 public slots:
 	void testActivation(const QString& s);
+	//HACK: try to get rid of this in the future.
+	void fakeActivation();
 	virtual void revertModelData(QWidget* widget, QAbstractItemDelegate::EndEditHint hint) = 0;
 protected:
 	QAbstractItemModel *model;