[gnome-panel] widget: calculate correct applet size

[Alberts Muktupāvels <muktupavels src gnome org>]

commit dc1100165a840c39b4acd6fb533373e5f7594910
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Fri Apr 30 23:37:25 2021 +0300

    widget: calculate correct applet size
    
    gtk_widget_get_preferred_size will not return correct size for
    applets that use height-for-width or width-for-height size request
    mode. With width-for-height mode gtk_widget_get_preferred_size
    first will get minimum height and then will get minimum width for
    calculated height while we really want minimum width for actual
    panel size if expand_minor is TRUE.

 gnome-panel/panel-widget.c | 58 ++++++++++++++++++++++++++++++++++------------
 1 file changed, 43 insertions(+), 15 deletions(-)
---
diff --git a/gnome-panel/panel-widget.c b/gnome-panel/panel-widget.c
index 0bf072091..432cb68d3 100644
--- a/gnome-panel/panel-widget.c
+++ b/gnome-panel/panel-widget.c
@@ -1488,6 +1488,45 @@ queue_resize_on_all_applets(PanelWidget *panel)
        }
 }
 
+static void
+get_preferred_size (PanelWidget    *self,
+                    AppletData     *ad,
+                    GtkRequisition *minimum_size)
+{
+  if (self->orient == GTK_ORIENTATION_HORIZONTAL)
+    {
+      if (ad->expand_minor)
+        minimum_size->height = self->sz;
+      else
+        gtk_widget_get_preferred_height (ad->applet,
+                                         &minimum_size->height,
+                                         NULL);
+
+      gtk_widget_get_preferred_width_for_height (ad->applet,
+                                                 minimum_size->height,
+                                                 &minimum_size->width,
+                                                 NULL);
+    }
+  else if (self->orient == GTK_ORIENTATION_VERTICAL)
+    {
+      if (ad->expand_minor)
+        minimum_size->width = self->sz;
+      else
+        gtk_widget_get_preferred_width (ad->applet,
+                                        &minimum_size->width,
+                                        NULL);
+
+      gtk_widget_get_preferred_height_for_width (ad->applet,
+                                                 minimum_size->width,
+                                                 &minimum_size->height,
+                                                 NULL);
+    }
+  else
+    {
+      g_assert_not_reached ();
+    }
+}
+
 static void
 panel_widget_size_allocate(GtkWidget *widget, GtkAllocation *allocation)
 {
@@ -1532,16 +1571,13 @@ panel_widget_size_allocate(GtkWidget *widget, GtkAllocation *allocation)
 
                        ad = list->data;
 
-                       gtk_widget_get_preferred_size (ad->applet, &chreq, NULL);
+                       get_preferred_size (panel, ad, &chreq);
 
                        ad->constrained = i;
                        
                        challoc.width = chreq.width;
                        challoc.height = chreq.height;
                        if(panel->orient == GTK_ORIENTATION_HORIZONTAL) {
-                               if (ad->expand_minor)
-                                       challoc.height = allocation->height;
-
                                if (ad->expand_major && ad->size_hints) {
                                        int width = panel->applets_using_hint[applet_using_hint_index].size;
                                        applet_using_hint_index++;
@@ -1552,9 +1588,6 @@ panel_widget_size_allocate(GtkWidget *widget, GtkAllocation *allocation)
                                challoc.x = ltr ? ad->constrained : panel->size - ad->constrained - 
challoc.width;
                                challoc.y = allocation->height / 2 - challoc.height / 2;
                        } else {
-                               if (ad->expand_minor)
-                                       challoc.width = allocation->width;
-
                                if (ad->expand_major && ad->size_hints) {
                                        int height = panel->applets_using_hint[applet_using_hint_index].size;
                                        applet_using_hint_index++;
@@ -1588,7 +1621,7 @@ panel_widget_size_allocate(GtkWidget *widget, GtkAllocation *allocation)
 
                        ad = list->data;
 
-                       gtk_widget_get_preferred_size (ad->applet, &chreq, NULL);
+                       get_preferred_size (panel, ad, &chreq);
 
                        if (!ad->expand_major || !ad->size_hints) {
                                if(panel->orient == GTK_ORIENTATION_HORIZONTAL)
@@ -1614,21 +1647,16 @@ panel_widget_size_allocate(GtkWidget *widget, GtkAllocation *allocation)
 
                        ad = list->data;
 
-                       gtk_widget_get_preferred_size (ad->applet, &chreq, NULL);
+                       get_preferred_size (panel, ad, &chreq);
+
                        challoc.width = chreq.width;
                        challoc.height = chreq.height;
                        if(panel->orient == GTK_ORIENTATION_HORIZONTAL) {
                                challoc.width = ad->cells;
-                               if (ad->expand_minor) {
-                                       challoc.height = allocation->height;
-                               }
                                challoc.x = ltr ? ad->constrained : panel->size - ad->constrained - 
challoc.width;
                                challoc.y = allocation->height / 2 - challoc.height / 2;
                        } else {
                                challoc.height = ad->cells;
-                               if (ad->expand_minor) {
-                                       challoc.width = allocation->width;
-                               }
                                challoc.x = allocation->width / 2 - challoc.width / 2;
                                challoc.y = ad->constrained;
                        }