Overview

This document describes the mechanism of functional buttons support for the Opera TV Store.

Functional buttons allow content developers to use hardware buttons in their applications, despite the different characteristics of various hardware their application is used by. This is achieved by mapping hardware-specific key codes like “37” to more generic key codes (functional codes) like VK_LEFT.

Functional buttons provide support for such basic keys as left, right, up, down or select. They can also be used as shortcuts to commonly used functions, such as “options” or “red key”.

Functional buttons list and JS APIs

This API can easily be added to an application with the inclusion of the following script element:

Full API as specified in this document is available after such inclusion. Without the inclusion Javascript key codes such as VK_RED will be available but helper functions defined in the opera.tv object will not.

List of available functional buttons

Example hardware key	JavaScript key code	Comment
←	VK_LEFT	Always available*
→	VK_RIGHT	Always available*
↑	VK_UP	Always available*
↓	VK_DOWN	Always available*
Confirm/Select/OK	VK_ENTER	Always available*
Exit	N/A	Always available (handled by native firmware)
Back/Return	VK_BACK_SPACE	Optional but recommended
BLUE	VK_BLUE	Optional but recommended
RED	VK_RED	Optional but recommended
GREEN	VK_GREEN	Optional but recommended
YELLOW	VK_YELLOW	Optional but recommended
Menu	VK_MENU	Optional
0	VK_0	Optional
1	VK_1	Optional
2	VK_2	Optional
3	VK_3	Optional
4	VK_4	Optional
5	VK_5	Optional
6	VK_6	Optional
7	VK_7	Optional
8	VK_8	Optional
9	VK_9	Optional
PLAY	VK_PLAY	Optional
PAUSE	VK_PAUSE	Optional
STOP	VK_STOP	Optional
NEXT	VK_TRACK_NEXT	Optional
PREV	VK_TRACK_PREV	Optional
FF (Fast-Forward)	VK_FAST_FWD	Optional
REWIND	VK_REWIND	Optional
SUBTITLE	VK_SUBTITLE	Optional
INFORMATION	VK_INFO	Optional

*Confirm, exit and directional buttons are mandatory, so they are always available for the end user via the remote control of any device that the Opera TV Store is integrated with. The exit key is handled by the native application to ensure that each application can be closed, therefore VK_EXIT will not be sent to the application.

Not supported buttons should return null value.

Buttons event API

Key events should be reached via standard JavaScript function or in HTML:

In HTML for a particular element:

In JavaScript use one of the following:

object.onkeypress = handler;
object.addEventListener ("keypress", handler, useCapture);
object.attachEvent ("onkeypress", handler);

To get the pressed key, use: event.keyCode in the handler function:

function handler(event){
    if (VK_RED == event.keyCode){
        ShowRedMenu();
    }
}

List of available buttons API

The buttons list is reachable via the functional button object and contains the buttons list supported by the device with paths to the button’s graphic representation:

opera.tv.getButtonsList();

Key for returned list is button code and value of that key is button name. Example implementation of the getButtonsList function:

Return
{
   [val(VK_LEFT)]: ‘VK_LEFT’,
   [val(VK_BACK)]: ‘VK_BACK’,
   [val(VK_MENU)]: ‘VK_MENU’
}

Example usage:

var list = opera.tv.getButtonsList();

Specific button check API

Availability of specific button can be checked as well as follows:

opera.tv.isButtonSupported(buttonID);

Returns true if a button with buttonID exists and is supported by the device, or false if it is not supported.

Example usage:

if(opera.tv.isButtonSupported(VK_RED))
ShowRedButton();

The same can be achieved with:

if(VK_RED)
ShowRedButton();