PyMaemo/UI tutorial/Additions to GTK+

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Hildon defines the following sizes to be used as sizes for widgets such as buttons or entries in your Hildon application.
Hildon defines the following sizes to be used as sizes for widgets such as buttons or entries in your Hildon application.
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Note: these constants are all defined in the gtk module.
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Revision as of 21:17, 8 December 2009

Contents

Additions to GTK+

A Hildon application might use any Gtk widget but in some cases could be needed to adapt those widgets to get that they fit perfectly.

Hildon provides a set of convenience functions to do that. The next sections explains these additions.

Hildon Size Types

Hildon defines the following sizes to be used as sizes for widgets such as buttons or entries in your Hildon application.

Note: these constants are all defined in the gtk module.

Const Description
HILDON_SIZE_HALFSCREEN_WIDTH set to 50% screen width
HILDON_SIZE_FULLSCREEN_WIDTH set to 100% screen width
HILDON_SIZE_AUTO_HEIGHT set to automatic height
HILDON_SIZE_FINGER_HEIGHT set to finger height
HILDON_SIZE_THUMB_HEIGHT set to thumb height
HILDON_SIZE_AUTO set to automatic width and automatic height

Hildon widgets allows to set their sizes in their construction functions, but in case you want to set the size of a GTK+ widget, Hildon also provides functions to do that:

   GtkButton(size)
   GtkToggleButton(size)
   GtkRadioButton(type_size, group)
   hildon_gtk_radio_button_new_from_widget(size, radio_group_member)

UI Modes

Hildon defines two modes in the UI that change the way user interacts with certain widgets. The main purpose of these modes is to enable direct manipulation of items, while still allowing user to select single or multiple items, when it is necessary. The following modes are supported:

Normal mode

It is the default mode. In lists and grids, tapping on an item causes a direct action. In views, this direct action could open a new subview to perform a certain action with the item.

Edit mode

Edit mode is used in views. The purpose of this mode is providing multiple selection functionality in list or grid and providing standard UI for editing single content item.

Hildon provides the following functions to set mode for a treeview or icon view:

   GtkTreeView(mode)
   GtkTreeView(mode, model)
   hildon_gtk_tree_view_set_ui_mode(treeview, mode)
   GtkIconView(mode)
   GtkIconView(mode, model)
   hildon_gtk_icon_view_set_ui_mode(iconview, mode)

The enum HildonUIMode defines the following flags:

  • HILDON_UI_MODE_NORMAL
  • HILDON_UI_MODE_EDIT

When you use a list or grid in edit mode inside a window you should use a hildon.EditToolbar to control the edition and set the window to fullscreen, building an Edit subview. To know more about edit views you can check chapter toolbars. In that chapter you can check an example of HildonToolbar which uses the concepts explained above.

Seek bars

The seek bars are useful to select a value from a range of predetermined values by adjusting the slider with a finger. These seek bars could be horizontal or vertical and are implemented using GtkVScale and GtkHScale. Thus, you can use this GTK+ widget in your Hildon application as seek bar but you should use following creation function instead of the GTK ones:

   GtkHScale()
   GtkVScale()

Scales created by using these constructors has a hildonized behavior, meaning that when user tap or click in a point of the bar immediately jumps to the desired position.

Progress indicators

A convenience way to inform the user that a long-term task is being performed is to show a progress indicator icon in the window or dialog title.

Hildon provides the following function to show a progress icon. This function applies to hildon.Window and gtk.Dialog.

   def hildon_gtk_window_set_progress_indicator(window, state)

The argument state should be 1 to show the indicator and 0 to hide it.

Here, a little example that sets a progress indicator in a GtkDialog. Click outside the dialog to close the example.

   # Based on C code from:
   # "Hildon Tutorial" version 2009-04-28
   # Example 8.1, "Adding a progress indicator to a dialog"
   
   import gtk
   import hildon
   
   def main():
       dialog = gtk.Dialog()
       dialog.set_title("Performing a long task")
       dialog.show_all()
       hildon.hildon_gtk_window_set_progress_indicator(dialog, 1)
       dialog.run()
   
   if __name__ == "__main__":
       main()


Additionally, if you consider that aditional text information should be give to the user you could use an informational banner.

Another convenience way to indicate to users that a long operation is being performed is using the gtk.ProgressBar widget. This is the usual way in GTK+ applications and you can use them like you would use them in a GTK+ application. This widget is specially useful if you need to show the status of the operation.