.. _button_en:

Button
******

The button element provides a push button widget. Some elements like `Legend <../elements/legend.html>`_ , `Layertree <layertree.html>`_, `FeatureInfo <feature_info.html>`_, `Line/Area Ruler <ruler.html>`_ and  `PrintClient <printclient.html>`_ need a button to be displayed/activated if not defined in a frame.

Buttons optionally can be grouped, so that only one button in a group can be active at any given time. This is done by the group paramter.
You can define a button that refers to a website or script using the click paramter.

Configuration
=============

.. image:: ../../../../../figures/button_configuration.png
     :scale: 80

* **Show label:** Enable or disable text (title) next to the button.
* **Title:** Title of the element. The title will be listed in "Layouts" and allows to distinguish between different buttons. It will be indicated if "Show label" is activated.
* **Tooltip:** Text, that will be indicated if the mouse hovers over the button for a longer time.
* **Icon:** Symbol of the button. Based on a CSS class.
* **Target:** Target element (Title(ID)) of the button. The target element will be triggered by clicking on the button. (e.g.: Print).
* **Click:** Refers to a website or a script (e.g.: http://mapbender3.org).
* **Group:** Adds the element to a group. Only one button of the group may be activated.
* **Action:** Method that is invoked when the button is activated. 
* **Deactivate:** Method that is invoked when the button is disabled.


YAML-Definition:
----

.. code-block:: yaml

    title:        # title
    tooltip:      # text to use as tooltip
    icon: ~       # icon CSS class to use
    label: true   # false/true to label the button, default is true
    target: ~     # title (Id) of target element
    click:        # refer to a website or script like http://mapbender3.org
    group: ~      # group to put the button into. Only one button per group can be active
    action: ~     # method of target to call when button is activated
    deactivate: ~ # method of target to call when button is deactivated

Class, Widget & Style
=====================

* **Class:** Mapbender\\CoreBundle\\Element\\Button
* **Widget:** mapbender.mbButton (mapbender.element.button.js)
* **Style:** mapbender.elements.css

HTTP Callbacks
==============

None.

JavaScript API
==============

activate
--------

Activates button. Gets called on click if button is deactivated.

deactivate
----------

Deactivates button. Gets called on click if button is active or when another button of the same group gets activated.

JavaScript Signals
==================

None.