[gnome-system-monitor/zbrown/tnum: 5/5] general: enable tabular numbers font feature

[Robert Roth <robertroth src gnome org>]

commit 12256992e4c606bb14ce72965e0c40409c156002
Author: Zander Brown <zbrown gnome org>
Date:   Mon Sep 21 17:04:17 2020 +0100

    general: enable tabular numbers font feature
    
    Use the tnum font feature to ensure numbers line up and reduce movement
    in the process, resource, filesystems & memory map views

 src/disks.cpp      | 19 +++++++++++++++++--
 src/interface.cpp  |  2 +-
 src/load-graph.cpp | 20 +++++++++++++-------
 src/memmaps.cpp    |  5 +++++
 src/proctable.cpp  | 28 ++++++++++++++++++++++++++++
 src/util.cpp       | 50 ++++++++++++++++++++++++++++++++++++++++++--------
 src/util.h         |  2 ++
 7 files changed, 108 insertions(+), 18 deletions(-)
---
diff --git a/src/disks.cpp b/src/disks.cpp
index fe6c7e10..fe79fae2 100644
--- a/src/disks.cpp
+++ b/src/disks.cpp
@@ -345,6 +345,7 @@ create_disk_view(GsmApplication *app, GtkBuilder *builder)
     GtkListStore *model;
     GtkTreeViewColumn *col;
     GtkCellRenderer *cell;
+    PangoAttrList *attrs = NULL;
     guint i;
 
     init_volume_monitor (app);
@@ -418,11 +419,18 @@ create_disk_view(GsmApplication *app, GtkBuilder *builder)
             case DISK_TOTAL:
             case DISK_FREE:
             case DISK_AVAIL:
-                g_object_set(cell, "xalign", 1.0f, NULL);
                 gtk_tree_view_column_set_cell_data_func(col, cell,
                                                         &procman::size_si_cell_data_func,
                                                         GUINT_TO_POINTER(i),
                                                         NULL);
+
+                attrs = make_tnum_attr_list ();
+                g_object_set (cell,
+                              "attributes", attrs,
+                              "xalign", 1.0f,
+                              NULL);
+                g_clear_pointer (&attrs, pango_attr_list_unref);
+
                 break;
 
             default:
@@ -437,7 +445,14 @@ create_disk_view(GsmApplication *app, GtkBuilder *builder)
 
     col = gtk_tree_view_column_new();
     cell = gtk_cell_renderer_text_new();
-    g_object_set(cell, "xalign", 1.0f, NULL);
+
+    attrs = make_tnum_attr_list ();
+    g_object_set (cell,
+                  "attributes", attrs,
+                  "xalign", 1.0f,
+                  NULL);
+    g_clear_pointer (&attrs, pango_attr_list_unref);
+
     gtk_tree_view_column_set_min_width(col, 72);
     gtk_tree_view_column_set_sizing(col, GTK_TREE_VIEW_COLUMN_FIXED);
     gtk_tree_view_column_pack_start(col, cell, FALSE);
diff --git a/src/interface.cpp b/src/interface.cpp
index fac941c1..1b9e0aa1 100644
--- a/src/interface.cpp
+++ b/src/interface.cpp
@@ -242,7 +242,7 @@ create_sys_view (GsmApplication *app, GtkBuilder * builder)
         gtk_widget_show (GTK_WIDGET (label));
         g_free (label_text);
 
-        cpu_label = GTK_LABEL (gtk_label_new (NULL));
+        cpu_label = make_tnum_label ();
 
         /* Reserve some space to avoid the layout changing with the values. */
         gtk_label_set_width_chars(cpu_label, 6);
diff --git a/src/load-graph.cpp b/src/load-graph.cpp
index 9d874b19..b70c7824 100644
--- a/src/load-graph.cpp
+++ b/src/load-graph.cpp
@@ -60,6 +60,7 @@ static void draw_background(LoadGraph *graph) {
     unsigned num_bars;
     char *caption;
     PangoLayout* layout;
+    PangoAttrList *attrs = NULL;
     PangoFontDescription* font_desc;
     PangoRectangle extents;
     cairo_surface_t *surface;
@@ -87,6 +88,11 @@ static void draw_background(LoadGraph *graph) {
 
     cairo_paint_with_alpha (cr, 0.0);
     layout = pango_cairo_create_layout (cr);
+
+    attrs = make_tnum_attr_list ();
+    pango_layout_set_attributes (layout, attrs);
+    g_clear_pointer (&attrs, pango_attr_list_unref);
+
     gtk_style_context_get (context, GTK_STATE_FLAG_NORMAL, GTK_STYLE_PROPERTY_FONT, &font_desc, NULL);
     pango_font_description_set_size (font_desc, 0.8 * graph->fontsize * PANGO_SCALE);
     pango_layout_set_font_description (layout, font_desc);
@@ -785,17 +791,17 @@ LoadGraph::LoadGraph(guint type)
             n = GsmApplication::get()->config.num_cpus;
 
             for(guint i = 0; i < G_N_ELEMENTS(labels.cpu); ++i)
-                labels.cpu[i] = GTK_LABEL (gtk_label_new(NULL));
+                labels.cpu[i] = make_tnum_label ();
 
             break;
 
         case LOAD_GRAPH_MEM:
             n = 2;
-            labels.memory = GTK_LABEL (gtk_label_new(NULL));
+            labels.memory = make_tnum_label ();
             gtk_widget_set_valign (GTK_WIDGET (labels.memory), GTK_ALIGN_CENTER);
             gtk_widget_set_halign (GTK_WIDGET (labels.memory), GTK_ALIGN_START);
             gtk_widget_show (GTK_WIDGET (labels.memory));
-            labels.swap = GTK_LABEL (gtk_label_new(NULL));
+            labels.swap = make_tnum_label ();
             gtk_widget_set_valign (GTK_WIDGET (labels.swap), GTK_ALIGN_CENTER);
             gtk_widget_set_halign (GTK_WIDGET (labels.swap), GTK_ALIGN_START);
             gtk_widget_show (GTK_WIDGET (labels.swap));
@@ -805,25 +811,25 @@ LoadGraph::LoadGraph(guint type)
             memset(&net, 0, sizeof net);
             n = 2;
             net.max = 1;
-            labels.net_in = GTK_LABEL (gtk_label_new(NULL));
+            labels.net_in = make_tnum_label ();
             gtk_label_set_width_chars(labels.net_in, 10);
             gtk_widget_set_valign (GTK_WIDGET (labels.net_in), GTK_ALIGN_CENTER);
             gtk_widget_set_halign (GTK_WIDGET (labels.net_in), GTK_ALIGN_END);
             gtk_widget_show (GTK_WIDGET (labels.net_in));
 
-            labels.net_in_total = GTK_LABEL (gtk_label_new(NULL));
+            labels.net_in_total = make_tnum_label ();
             gtk_widget_set_valign (GTK_WIDGET (labels.net_in_total), GTK_ALIGN_CENTER);
             gtk_widget_set_halign (GTK_WIDGET (labels.net_in_total), GTK_ALIGN_END);
             gtk_label_set_width_chars(labels.net_in_total, 10);
             gtk_widget_show (GTK_WIDGET (labels.net_in_total));
 
-            labels.net_out = GTK_LABEL (gtk_label_new(NULL));
+            labels.net_out = make_tnum_label ();
             gtk_widget_set_valign (GTK_WIDGET (labels.net_out), GTK_ALIGN_CENTER);
             gtk_widget_set_halign (GTK_WIDGET (labels.net_out), GTK_ALIGN_END);
             gtk_label_set_width_chars(labels.net_out, 10);
             gtk_widget_show (GTK_WIDGET (labels.net_out));
 
-            labels.net_out_total = GTK_LABEL (gtk_label_new(NULL));
+            labels.net_out_total = make_tnum_label ();
             gtk_widget_set_valign (GTK_WIDGET (labels.net_out_total), GTK_ALIGN_CENTER);
             gtk_widget_set_halign (GTK_WIDGET (labels.net_out), GTK_ALIGN_END);
             gtk_label_set_width_chars(labels.net_out_total, 10);
diff --git a/src/memmaps.cpp b/src/memmaps.cpp
index 02053c79..8827d9f2 100644
--- a/src/memmaps.cpp
+++ b/src/memmaps.cpp
@@ -356,6 +356,7 @@ create_memmapsdata (GsmApplication *app)
     for (i = 0; i < MMAP_COL_MAX; i++) {
         GtkCellRenderer *cell;
         GtkTreeViewColumn *col;
+        PangoAttrList *attrs;
 
         cell = gtk_cell_renderer_text_new();
         col = gtk_tree_view_column_new();
@@ -366,6 +367,10 @@ create_memmapsdata (GsmApplication *app)
         gtk_tree_view_column_set_reorderable(col, TRUE);
         gtk_tree_view_append_column(GTK_TREE_VIEW(tree), col);
 
+        attrs = make_tnum_attr_list ();
+        g_object_set (cell, "attributes", attrs, NULL);
+        g_clear_pointer (&attrs, pango_attr_list_unref);
+
         switch (i) {
             case MMAP_COL_PRIVATE_CLEAN:
             case MMAP_COL_PRIVATE_DIRTY:
diff --git a/src/proctable.cpp b/src/proctable.cpp
index 3f0026e2..868b8afd 100644
--- a/src/proctable.cpp
+++ b/src/proctable.cpp
@@ -442,6 +442,7 @@ proctable_new (GsmApplication * const app)
     for (i = COL_USER; i <= COL_PRIORITY; i++) {
         GtkTreeViewColumn *col;
         GtkCellRenderer *cell;
+        PangoAttrList *attrs = NULL;
 
 #ifndef HAVE_WNCK
         if (i == COL_MEMXSERVER)
@@ -526,6 +527,33 @@ proctable_new (GsmApplication * const app)
                 break;
         }
 
+        // Tabular Numbers
+        switch (i) {
+#ifdef HAVE_WNCK
+            case COL_MEMXSERVER:
+#endif
+            case COL_PID:
+            case COL_VMSIZE:
+            case COL_MEMRES:
+            case COL_MEMSHARED:
+            case COL_MEM:
+            case COL_CPU:
+            case COL_CPU_TIME:
+            case COL_DISK_READ_TOTAL:
+            case COL_DISK_WRITE_TOTAL:
+            case COL_DISK_READ_CURRENT:
+            case COL_DISK_WRITE_CURRENT:
+            case COL_START_TIME:
+            case COL_NICE:
+            case COL_WCHAN:
+                attrs = make_tnum_attr_list ();
+                g_object_set (cell, "attributes", attrs, NULL);
+                g_clear_pointer (&attrs, pango_attr_list_unref);
+                break;
+            default:
+                break;
+        }
+
         // sorting
         switch (i) {
 #ifdef HAVE_WNCK
diff --git a/src/util.cpp b/src/util.cpp
index 044fc925..07f7c5fe 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -373,13 +373,17 @@ namespace procman
         g_value_unset(&value);
 
         if (size == 0) {
-            char *str = g_strdup_printf ("<i>%s</i>", _("N/A"));
-            g_object_set(renderer, "markup", str, NULL);
-            g_free(str);
+            g_object_set (renderer,
+                          "text", _("N/A"),
+                          "style", PANGO_STYLE_ITALIC,
+                          NULL);
         }
         else {
             char *str = g_format_size_full(size, G_FORMAT_SIZE_IEC_UNITS);
-            g_object_set(renderer, "text", str, NULL);
+            g_object_set (renderer,
+                          "text", str,
+                          "style", PANGO_STYLE_NORMAL,
+                          NULL);
             g_free(str);
         }
 
@@ -412,12 +416,16 @@ namespace procman
         g_value_unset(&value);
 
         if (size == 0) {
-            char *str = g_strdup_printf ("<i>%s</i>", _("N/A"));
-            g_object_set(renderer, "markup", str, NULL);
-            g_free(str);
+            g_object_set (renderer,
+                          "text", _("N/A"),
+                          "style", PANGO_STYLE_ITALIC,
+                          NULL);
         }
         else {
-            g_object_set(renderer, "text", procman::format_rate(size, FALSE).c_str(), NULL);
+            g_object_set (renderer,
+                          "text", procman::format_rate(size, FALSE).c_str(),
+                          "style", PANGO_STYLE_NORMAL,
+                          NULL);
         }
 
     }
@@ -635,3 +643,29 @@ get_monospace_system_font_name ()
 {
     return Gio::Settings::create ("org.gnome.desktop.interface")->get_string ("monospace-font-name");
 }
+
+
+GtkLabel *
+make_tnum_label (void)
+{
+    PangoAttrList *attrs = make_tnum_attr_list ();
+    GtkWidget *label = gtk_label_new (NULL);
+
+    gtk_label_set_attributes (GTK_LABEL (label), attrs);
+
+    g_clear_pointer (&attrs, pango_attr_list_unref);
+
+    return GTK_LABEL (label);
+}
+
+
+PangoAttrList *
+make_tnum_attr_list (void)
+{
+    PangoAttrList *attrs = NULL;
+
+    attrs = pango_attr_list_new ();
+    pango_attr_list_insert (attrs, pango_attr_font_features_new ("tnum=1"));
+
+    return attrs;
+}
diff --git a/src/util.h b/src/util.h
index d76244e4..8e94766c 100644
--- a/src/util.h
+++ b/src/util.h
@@ -25,6 +25,8 @@ procman_debug_real(const char *file, int line, const char *func,
 #define procman_debug(FMT, ...) procman_debug_real(__FILE__, __LINE__, __func__, FMT, ##__VA_ARGS__)
 
 Glib::ustring get_monospace_system_font_name (void);
+GtkLabel *make_tnum_label (void);
+PangoAttrList *make_tnum_attr_list (void);
 
 inline string make_string(char *c_str)
 {