sounds plausible. have a patch ?

Created attachment 295371 [details] [review]
scrolledwindow: add a new edge-reached signal

This will be used to just detect when an edge of the scrollable area is
reached - as opposed to the edge-overshot signal that is emitted when
the user scrolls past the edge.

--

This is a solution me and Carlos agreed upon; add a different signal, since the intent of "edge-overshot" is really to detect when scrolling goes past the boundaries of the scrollable area (e.g. to trigger a refresh), as opposed to detecting when the edge is reached.

Review of attachment 295371 [details] [review]:

Looks fine to me, with those cosmetic fixes

::: gtk/gtkscrolledwindow.c
@@ +674,3 @@
                   G_TYPE_NONE, 1, GTK_TYPE_POSITION_TYPE);
+  /**
+   * GtkScrolledWindow::edge-reached:

Please add a newline before the comment

@@ +678,3 @@
+   * @pos: edge side that was reached
+   *
+   * The ::edge-reached signal is emitted whenever user initiated scrolling

Should probably be user-initiated

@@ +3272,3 @@
+    edge_pos = (edge_pos == GTK_POS_LEFT) ? GTK_POS_RIGHT : GTK_POS_LEFT;
+
+  g_signal_emit (scrolled_window, signals[EDGE_REACHED], 0, edge_pos);

I'll point out that you can have value == lower and value == upper - page at the same time. But then, in that case the value should be fixed at lower, and no value-changed signal will ever be emitted...

@@ +3282,3 @@
   GtkScrolledWindowPrivate *priv = scrolled_window->priv;
 
+  maybe_emit_edge_reached (scrolled_window, adjustment);

I guess in theory, you can also end up with value == lower or value == upper by changing the limits - probably a corner case not worth worrying about.

Pushed to master with those changes - thanks for the review.

Attachment 295371 [details] pushed as 404e275 - scrolledwindow: add a new edge-reached signal