Sugar.graphics.alert

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Revision as of 12:33, 26 June 2008 by Fanwar (talk | contribs) (Class: Alert)
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Class: Alert

Alerts appear at the top of the body of your activity, just below the toolbox if it is visible. The image below shows what a simple alert looks like.

Sugar-simple-alert.jpg


How do I create a simple alert message?

You can create the most basic alert message by first creating a new instance of the Alert class and then calling the add_alert() method for your activity.

from sugar.graphics.alert import Alert
...
       # Create a new simple alert
        alert = Alert()
        # Populate the title and text body of the alert. 
        alert.props.title=_('Title of Alert Goes Here')
        alert.props.msg = _('Text message of alert goes here')
        # Call the add_alert() method (inherited via the sugar.graphics.Window superclass of Activity)
        # to add this alert to the activity window. 
        self.add_alert(alert)
        alert.show()


How do I create an alert message with a button that allows a user response to the alert?

The _alert_user() method below is called to alert the user about something (here it is very generic). In this example, we add a simple 'OK' button that the user can click. When this button is clicked, the _alert_response_cb() method gets called, which removes the alert from the screen.


from sugar.graphics.alert import Alert
...
    def _alert_user(self):
        # Create a new simple alert
        alert = Alert()
        # Populate the title and text body of the alert. 
        alert.props.title=_('Title of Alert Goes Here')
        alert.props.msg = _('Text message of alert goes here')

        #Add an 'OK' Button
        ok_icon = Icon(icon_name='ok-button')
        ok_icon.set_pixel_size(50)
        alert.add_button(gtk.RESPONSE_OK, _('Okay'), ok_icon)
        alert.connect('response', self._alert_response_cb)

        # Call the add_alert() method (inherited via the sugar.graphics.Window superclass of Activity)
        # to add this alert to the activity window. 
        self.add_alert(alert)
        alert.show()


    def _alert_response_cb(self, alert, response_id):
        if response_id is gtk.RESPONSE_OK:
            self.remove_alert(alert)

Class: ConfirmationAlert

What is special about a confirmation alert and how do I use it in my activity?

A confirmation alert is a nice shortcut from a standard Alert because it comes with 'OK' and 'Cancel' buttons already built-in. When clicked, the 'OK' button will emit a response with a response_id of gtk.RESPONSE_OK, while the 'Cancel' button will emit gtk.RESPONSE_CANCEL.

The code below shows how a ConfirmationAlert is created. It also shows a response method that takes care of one of the two action buttons being clicked.

from sugar.graphics.alert import ConfirmationAlert
...
    #### Method: _alert_confirmation, create a Confirmation alert (with ok and cancel buttons standard)
    # and add it to the UI. 
    def _alert_confirmation(self):
        alert = ConfirmationAlert()
        alert.props.title=_('Title of Alert Goes Here')
        alert.props.msg = _('Text message of alert goes here')
        alert.connect('response', self._alert_response_cb)
        self.add_alert(alert)


    #### Method: _alert_response_cb, called when an alert object throws a response event. 
    def _alert_response_cb(self, alert, response_id):
        #remove the alert from the screen, since either a response button was clicked or
        #there was a timeout
        self.remove_alert(alert)

        #Do any work that is specific to the type of button clicked. 
        if response_id is gtk.RESPONSE_OK:
            print 'Ok Button was clicked. Do any work upon ok here ...'
        elif response_id is gtk.RESPONSE_CANCEL:
            print 'Cancel Button was clicked.'

Class: TimeoutAlert

Class: NotifyAlert