[nautilus/wip/antoniof/flowbox-to-gridview: 16/16] view-icon-controller: Prevent spontaneous scrolling when loading

[António Fernandes <antoniof src gnome org>]

commit f36f912ad59108e77b0f24b5e34e478387d430e9
Author: António Fernandes <antoniof gnome org>
Date:   Wed Feb 2 19:31:00 2022 +0000

    view-icon-controller: Prevent spontaneous scrolling when loading
    
    When loading a directory with many files, GtkGridView keeps scrolling
    down spontaneously.
    
    This happens because GtkListBase anchoring doesn't cope well with our
    lazy loading.
    
    Use a hacky workaround to prevent scrolling while we are at the top.

 src/nautilus-view-icon-controller.c | 10 ++++++++++
 1 file changed, 10 insertions(+)
---
diff --git a/src/nautilus-view-icon-controller.c b/src/nautilus-view-icon-controller.c
index 0d527aa02..215b82b39 100644
--- a/src/nautilus-view-icon-controller.c
+++ b/src/nautilus-view-icon-controller.c
@@ -1104,10 +1104,20 @@ real_add_files (NautilusFilesView *files_view,
     NautilusViewIconController *self = NAUTILUS_VIEW_ICON_CONTROLLER (files_view);
     g_autoptr (GQueue) files_queue = NULL;
     g_autoptr (GQueue) item_models = NULL;
+    gdouble adjustment_value;
 
     files_queue = convert_glist_to_queue (files);
     item_models = convert_files_to_item_models (self, files_queue);
     nautilus_view_model_add_items (self->model, item_models);
+
+    /* GtkListBase anchoring doesn't cope well with our lazy loading.
+     * Assuming that GtkListBase|list.scroll-to-item resets the anchor to 0, use
+     * that as a workaround to prevent scrolling while we are at the top. */
+    adjustment_value = gtk_adjustment_get_value (self->vadjustment);
+    if (G_APPROX_VALUE (adjustment_value, 0.0, DBL_EPSILON))
+    {
+        gtk_widget_activate_action (GTK_WIDGET (self->view_ui), "list.scroll-to-item", "u", 0);
+    }
 }