From 97f8979c535665dda1f7d7e66572d52ea2220888 Mon Sep 17 00:00:00 2001
From: Georges Basile Stavracas Neto <georges.stavracas@gmail.com>
Date: Tue, 27 Sep 2016 21:48:07 -0300
Subject: [PATCH] month-view: hide overflow popover on drag and drop

When the user starts a drag operation from the overflow popover,
it should hide itself, otherwise it can block dropping the event
below it. Currently, this is not what happens.

Fix that by making the overflow popover a drag and drop target,
and hide it when it detects drag movement.

https://bugzilla.gnome.org/show_bug.cgi?id=771663
---
 src/gcal-month-view.c | 32 ++++++++++++++++++++++++++++++--
 1 file changed, 30 insertions(+), 2 deletions(-)

diff --git a/src/gcal-month-view.c b/src/gcal-month-view.c
index 6f90bec6..f32f8fa6 100644
--- a/src/gcal-month-view.c
+++ b/src/gcal-month-view.c
@@ -838,9 +838,14 @@ gcal_month_view_drag_motion (GtkWidget      *widget,
 
   /* Setup the drag highlight */
   if (priv->dnd_cell != -1)
-    gtk_drag_highlight (widget);
+    {
+      gtk_drag_highlight (widget);
+      gtk_widget_hide (priv->overflow_popover);
+    }
   else
-    gtk_drag_unhighlight (widget);
+    {
+      gtk_drag_unhighlight (widget);
+    }
 
   /*
    * Sets the status of the drag - if it fails, sets the action to 0 and
@@ -950,6 +955,14 @@ gcal_month_view_drag_leave (GtkWidget      *widget,
   gtk_widget_queue_draw (widget);
 }
 
+static gboolean
+cancel_dnd_from_overflow_popover (GtkWidget *popover)
+{
+  gtk_widget_hide (popover);
+
+  return FALSE;
+}
+
 static void
 add_new_event_button_cb (GtkWidget *button,
                          gpointer   user_data)
@@ -1028,6 +1041,10 @@ gcal_month_view_init (GcalMonthView *self)
   priv->overflow_popover = gtk_popover_new (GTK_WIDGET (self));
   gtk_style_context_add_class (gtk_widget_get_style_context (priv->overflow_popover), "events");
   g_signal_connect (priv->overflow_popover, "hide", G_CALLBACK (overflow_popover_hide), self);
+  g_signal_connect_swapped (priv->overflow_popover,
+                            "drag-motion",
+                            G_CALLBACK (cancel_dnd_from_overflow_popover),
+                            priv->overflow_popover);
 
   grid = gtk_grid_new ();
   g_object_set (grid, "row-spacing", 6, "orientation", GTK_ORIENTATION_VERTICAL, NULL);
@@ -1053,6 +1070,17 @@ gcal_month_view_init (GcalMonthView *self)
                      NULL,
                      0,
                      GDK_ACTION_MOVE);
+
+  /*
+   * Also set the overflow popover as a drop destination, so we can hide
+   * it when the user starts dragging an event that is inside the overflow
+   * list.
+   */
+  gtk_drag_dest_set (GTK_WIDGET (priv->overflow_popover),
+                     0,
+                     NULL,
+                     0,
+                     GDK_ACTION_MOVE);
 }
 
 static void