[gtk/fontconfig-speedup: 1/3] widget-factory: Improve the error states example

[Matthias Clasen <matthiasc src gnome org>]

commit 8acd60fda9948f5429f7aa6e46ee1dc7ecf3e047
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Aug 15 08:26:28 2020 -0400

    widget-factory: Improve the error states example
    
    Elaborate the error state handling, and make it show
    delayed states in GtkSwitch too.

 demos/widget-factory/widget-factory.c  | 51 ++++++++++++++++++++++++++++++++++
 demos/widget-factory/widget-factory.ui |  7 +++--
 2 files changed, 55 insertions(+), 3 deletions(-)
---
diff --git a/demos/widget-factory/widget-factory.c b/demos/widget-factory/widget-factory.c
index 0b17ed05d4..48329d4018 100644
--- a/demos/widget-factory/widget-factory.c
+++ b/demos/widget-factory/widget-factory.c
@@ -1896,6 +1896,48 @@ validate_more_details (GtkEntry   *entry,
     }
 }
 
+static gboolean
+mode_switch_state_set (GtkSwitch *sw, gboolean state)
+{
+  GtkWidget *dialog = gtk_widget_get_ancestor (GTK_WIDGET (sw), GTK_TYPE_DIALOG);
+  GtkWidget *scale = GTK_WIDGET (g_object_get_data (G_OBJECT (dialog), "level_scale"));
+  GtkWidget *label = GTK_WIDGET (g_object_get_data (G_OBJECT (dialog), "error_label"));
+
+  if (!state ||
+      (gtk_range_get_value (GTK_RANGE (scale)) > 50))
+    {
+      gtk_widget_hide (label);
+      gtk_switch_set_state (sw, state);
+    }
+  else
+    {
+      gtk_widget_show (label);
+    }
+
+  return TRUE;
+}
+
+static void
+level_scale_value_changed (GtkRange *range)
+{
+  GtkWidget *dialog = gtk_widget_get_ancestor (GTK_WIDGET (range), GTK_TYPE_DIALOG);
+  GtkWidget *sw = GTK_WIDGET (g_object_get_data (G_OBJECT (dialog), "mode_switch"));
+  GtkWidget *label = GTK_WIDGET (g_object_get_data (G_OBJECT (dialog), "error_label"));
+
+  if (gtk_switch_get_active (GTK_SWITCH (sw)) &&
+      !gtk_switch_get_state (GTK_SWITCH (sw)) &&
+      (gtk_range_get_value (range) > 50))
+    {
+      gtk_widget_hide (label);
+      gtk_switch_set_state (GTK_SWITCH (sw), TRUE);
+    }
+  else if (gtk_switch_get_state (GTK_SWITCH (sw)) &&
+          (gtk_range_get_value (range) <= 50))
+    {
+      gtk_switch_set_state (GTK_SWITCH (sw), FALSE);
+    }
+}
+
 static void
 activate (GApplication *app)
 {
@@ -1978,6 +2020,8 @@ activate (GApplication *app)
           "osd_frame_pressed", (GCallback)osd_frame_pressed,
           "age_entry_changed", (GCallback)age_entry_changed,
           "validate_more_details", (GCallback)validate_more_details,
+          "mode_switch_state_set", (GCallback)mode_switch_state_set,
+          "level_scale_value_changed", (GCallback)level_scale_value_changed,
           NULL);
   gtk_builder_set_scope (builder, scope);
   g_object_unref (scope);
@@ -2101,6 +2145,13 @@ activate (GApplication *app)
   widget = (GtkWidget *)gtk_builder_get_object (builder, "circular_button");
   g_signal_connect (widget, "clicked", G_CALLBACK (show_dialog), dialog);
 
+  widget = (GtkWidget *)gtk_builder_get_object (builder, "level_scale");
+  g_object_set_data (G_OBJECT (dialog), "level_scale", widget);
+  widget = (GtkWidget *)gtk_builder_get_object (builder, "mode_switch");
+  g_object_set_data (G_OBJECT (dialog), "mode_switch", widget);
+  widget = (GtkWidget *)gtk_builder_get_object (builder, "error_label");
+  g_object_set_data (G_OBJECT (dialog), "error_label", widget);
+
   dialog = (GtkWidget *)gtk_builder_get_object (builder, "selection_dialog");
   g_object_set_data (G_OBJECT (window), "selection_dialog", dialog);
   widget = (GtkWidget *)gtk_builder_get_object (builder, "text3");
diff --git a/demos/widget-factory/widget-factory.ui b/demos/widget-factory/widget-factory.ui
index fccbb520d9..b77fa7b2ca 100644
--- a/demos/widget-factory/widget-factory.ui
+++ b/demos/widget-factory/widget-factory.ui
@@ -3078,6 +3078,7 @@ bad things might happen.</property>
                 <property name="valign">baseline</property>
                 <property name="draw-value">0</property>
                 <property name="adjustment">adjustment1</property>
+                <signal name="value-changed" handler="level_scale_value_changed"/>
                 <layout>
                   <property name="column">1</property>
                   <property name="row">2</property>
@@ -3105,6 +3106,7 @@ bad things might happen.</property>
               <object class="GtkSwitch" id="mode_switch">
                 <property name="halign">start</property>
                 <property name="valign">baseline</property>
+                <signal name="state-set" handler="mode_switch_state_set"/>
                 <layout>
                   <property name="column">1</property>
                   <property name="row">3</property>
@@ -3112,12 +3114,11 @@ bad things might happen.</property>
               </object>
             </child>
             <child>
-              <object class="GtkLabel" id="switch_error">
+              <object class="GtkLabel" id="error_label">
                 <property name="visible">0</property>
                 <property name="halign">start</property>
                 <property name="valign">baseline</property>
-                <property name="label">Error!</property>
-                <property name="visible" bind-source="mode_switch" bind-property="active"></property>
+                <property name="label">Level too low</property>
                 <style>
                   <class name="error"/>
                 </style>