desktop: add trip selection dialog

A simple dialog to select a trip. Simply fill a QListWidget without
the model/view rigmarole. So much less painful! Of course that means
that the dialog has to be regenerated everytime it is used.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

desktop-widgets/tripselectiondialog.h

@@ -0,0 +1,23 @@
+// SPDX-License-Identifier: GPL-2.0
+#ifndef TRIPSELECTIONDIALOG_H
+#define TRIPSELECTIONDIALOG_H
+
+#include <QDialog>
+#include "ui_tripselectiondialog.h"
+
+struct dive_trip;
+
+class TripSelectionDialog : public QDialog {
+	Q_OBJECT
+private
+slots:
+	void selectionChanged();
+public:
+	TripSelectionDialog(QWidget *parent); // Must pass in MainWindow for QShortcut hackery.
+	dive_trip *getTrip(); // NULL if user canceled.
+private:
+	dive_trip *selectedTrip() const;
+	Ui::TripSelectionDialog ui;
+};
+
+#endif // TRIPSELECTIONDIALOG_H