[Sugar-devel] [PATCH sugar 2/2] Add feedback in Home View, List View when there are no matching entries - SL #3838

[Manuel Quiñones]

The scrolled window widget that contains the list of activities is
replaced by a message box when there are no matching entries.  This is
the same as the Journal does.  An alert can be packed also, so we use
pack_end to add the message box or the list of activities again.

Use Gtk.TreeModel.iter_n_children() [1] to count the matches, note
that this work only for tree model lists.

The message box widget is copied from the Journal listview.  Is done
in a separate class and can be generalized later.  The only important
change here is the icon colors: to make the 'system-search' icon look
ok, the stroke color and fill color were switched.

[1] http://developer.gnome.org/gtk3/stable/GtkTreeModel.html#gtk-tree-model-iter-n-children

Signed-off-by: Manuel Quiñones <manuq at laptop.org>
---
 src/jarabe/desktop/activitieslist.py | 102 +++++++++++++++++++++++++++++++----
 src/jarabe/desktop/homebox.py        |   1 +
 src/jarabe/desktop/viewtoolbar.py    |   9 ++++
 3 files changed, 103 insertions(+), 9 deletions(-)

diff --git a/src/jarabe/desktop/activitieslist.py b/src/jarabe/desktop/activitieslist.py
index ab62b58..6731df3 100644
--- a/src/jarabe/desktop/activitieslist.py
+++ b/src/jarabe/desktop/activitieslist.py
@@ -19,6 +19,7 @@ import os
 import logging
 from gettext import gettext as _
 
+import glib
 from gi.repository import GObject
 from gi.repository import Pango
 from gi.repository import GConf
@@ -31,6 +32,7 @@ from sugar3.graphics.icon import Icon, CellRendererIcon
 from sugar3.graphics.xocolor import XoColor
 from sugar3.graphics.menuitem import MenuItem
 from sugar3.graphics.alert import Alert
+from sugar3.graphics.icon import EventIcon
 
 from jarabe.model import bundleregistry
 from jarabe.view.palettes import ActivityPalette
@@ -50,7 +52,8 @@ class ActivitiesTreeView(Gtk.TreeView):
 
         self._query = ''
 
-        self.modify_base(Gtk.StateType.NORMAL, style.COLOR_WHITE.get_gdk_color())
+        self.modify_base(Gtk.StateType.NORMAL,
+                         style.COLOR_WHITE.get_gdk_color())
         self.set_headers_visible(False)
         selection = self.get_selection()
         selection.set_mode(Gtk.SelectionMode.NONE)
@@ -147,8 +150,14 @@ class ActivitiesTreeView(Gtk.TreeView):
         misc.launch(bundle)
 
     def set_filter(self, query):
+        """Set a new query and refilter the model, return the number
+        of matching activities.
+
+        """
         self._query = query.lower()
         self.get_model().refilter()
+        matches = self.get_model().iter_n_children(None)
+        return matches
 
     def __model_visible_cb(self, model, tree_iter, data):
         title = model[tree_iter][ListModel.COLUMN_TITLE]
@@ -296,30 +305,78 @@ class CellRendererActivityIcon(CellRendererIcon):
         self.emit('erase-activated', bundle_id)
 
 
+class ClearMessageBox(Gtk.EventBox):
+    def __init__(self, message, button_callback):
+        Gtk.EventBox.__init__(self)
+
+        self.modify_bg(Gtk.StateType.NORMAL,
+                       style.COLOR_WHITE.get_gdk_color())
+
+        alignment = Gtk.Alignment.new(0.5, 0.5, 0.1, 0.1)
+        self.add(alignment)
+        alignment.show()
+
+        box = Gtk.VBox()
+        alignment.add(box)
+        box.show()
+
+        icon = EventIcon(pixel_size=style.LARGE_ICON_SIZE,
+                         icon_name='system-search',
+                         stroke_color=style.COLOR_TRANSPARENT.get_svg(),
+                         fill_color=style.COLOR_BUTTON_GREY.get_svg())
+        box.pack_start(icon, expand=True, fill=False, padding=0)
+        icon.show()
+
+        label = Gtk.Label()
+        color = style.COLOR_BUTTON_GREY.get_html()
+        label.set_markup('<span weight="bold" color="%s">%s</span>' % ( \
+                color, glib.markup_escape_text(message)))
+        box.pack_start(label, expand=True, fill=False, padding=0)
+        label.show()
+
+        button = Gtk.Button(label=_('Clear search'))
+        button.connect('clicked', button_callback)
+        button.props.image = Icon(icon_name='dialog-cancel',
+                                  icon_size=Gtk.IconSize.BUTTON)
+        box.pack_start(button, expand=True, fill=False, padding=0)
+        button.show()
+
+
 class ActivitiesList(Gtk.VBox):
     __gtype_name__ = 'SugarActivitiesList'
 
+    __gsignals__ = {
+        'clear-clicked': (GObject.SignalFlags.RUN_FIRST, None, ([])),
+    }
+
     def __init__(self):
         logging.debug('STARTUP: Loading the activities list')
 
         Gtk.VBox.__init__(self)
 
-        scrolled_window = Gtk.ScrolledWindow()
-        scrolled_window.set_policy(Gtk.PolicyType.NEVER, Gtk.PolicyType.AUTOMATIC)
-        scrolled_window.set_shadow_type(Gtk.ShadowType.NONE)
-        scrolled_window.connect('key-press-event', self.__key_press_event_cb)
-        self.pack_start(scrolled_window, True, True, 0)
-        scrolled_window.show()
+        self._scrolled_window = Gtk.ScrolledWindow()
+        self._scrolled_window.set_policy(Gtk.PolicyType.NEVER,
+                                         Gtk.PolicyType.AUTOMATIC)
+        self._scrolled_window.set_shadow_type(Gtk.ShadowType.NONE)
+        self._scrolled_window.connect('key-press-event',
+                                      self.__key_press_event_cb)
+        self.pack_start(self._scrolled_window, True, True, 0)
+        self._scrolled_window.show()
 
         self._tree_view = ActivitiesTreeView()
         self._tree_view.connect('erase-activated', self.__erase_activated_cb)
-        scrolled_window.add(self._tree_view)
+        self._scrolled_window.add(self._tree_view)
         self._tree_view.show()
 
         self._alert = None
+        self._clear_message_box = None
 
     def set_filter(self, query):
-        self._tree_view.set_filter(query)
+        matches = self._tree_view.set_filter(query)
+        if matches == 0:
+            self._show_clear_message()
+        else:
+            self._hide_clear_message()
 
     def __key_press_event_cb(self, scrolled_window, event):
         keyname = Gdk.keyval_name(event.keyval)
@@ -339,6 +396,33 @@ class ActivitiesList(Gtk.VBox):
 
         return True
 
+    def _show_clear_message(self):
+        if self._clear_message_box in self.get_children():
+            return
+        if self._scrolled_window in self.get_children():
+            self.remove(self._scrolled_window)
+
+        self._clear_message_box = ClearMessageBox(
+            message=_('No matching activities'),
+            button_callback=self.__clear_button_clicked_cb)
+
+        self.pack_end(self._clear_message_box, True, True, 0)
+        self._clear_message_box.show()
+
+    def __clear_button_clicked_cb(self, button):
+        self.emit('clear-clicked')
+
+    def _hide_clear_message(self):
+        if self._scrolled_window in self.get_children():
+            return
+        if self._clear_message_box in self.get_children():
+            self.remove(self._clear_message_box)
+
+        self._clear_message_box = None
+
+        self.pack_end(self._scrolled_window, True, True, 0)
+        self._scrolled_window.show()
+
     def add_alert(self, alert):
         if self._alert is not None:
             self.remove_alert()
diff --git a/src/jarabe/desktop/homebox.py b/src/jarabe/desktop/homebox.py
index 875ecf6..17bb609 100644
--- a/src/jarabe/desktop/homebox.py
+++ b/src/jarabe/desktop/homebox.py
@@ -45,6 +45,7 @@ class HomeBox(Gtk.VBox):
 
         toolbar.connect('query-changed', self.__toolbar_query_changed_cb)
         toolbar.connect('view-changed', self.__toolbar_view_changed_cb)
+        toolbar.attach_to_clear(self._list_view)
 
         self._set_view(_FAVORITES_VIEW)
         self._query = ''
diff --git a/src/jarabe/desktop/viewtoolbar.py b/src/jarabe/desktop/viewtoolbar.py
index 340ab73..59798c6 100644
--- a/src/jarabe/desktop/viewtoolbar.py
+++ b/src/jarabe/desktop/viewtoolbar.py
@@ -92,6 +92,15 @@ class ViewToolbar(Gtk.Toolbar):
         self._favorites_button.hide()
         self._list_button.hide()
 
+    def attach_to_clear(self, widget):
+        widget.connect('clear-clicked', self.__clear_clicked_cb)
+
+    def __clear_clicked_cb(self, widget):
+        self.clear_query()
+
+    def clear_query(self):
+        self.search_entry.props.text = ''
+
     def _add_separator(self, expand=False):
         separator = Gtk.SeparatorToolItem()
         separator.props.draw = False
-- 
1.7.11.4