lighton()

Syntax:

[void] sysinfo.lighton(Int lighttarget, Int duration, Int intensity, Bool fadein)

Description:

The lighton method switches the specified target light on for a specified duration with the brightness defined by a specified light intensity.

Argument:

lighttarget:
+ +
Defines which target light should be turned on. Use one of the supported target light properties to specify a target light.
+ +
duration:
+ +
Defines the period during which the target light is switched on. The period is measured in milliseconds.
+
After the duration expires, the light state of the target will be changed to whatever state was caused by the last infinite time duration call. If there has not been a previous infinite time duration call in a session, the default state determined by the inactivity timer (system backlight timeout) is used.
+
If duration is lightinfiniteduration, the target light can be turned off only when some other light control method is called.
+
Duration can also have the maximum value of lightmaxduration
+ +
intensity:
+ +
Defines the intensity (brightness) of the light. If intensity is lightdefaultintensity, the device default intensity will be used.
+
Use the lightminintensity and the lightmaxintensity to detect the range of supported light intensity, and use any value between the range to avoid providing an invalid intensity value.
+ +

Note: All devices might not support a user-defined intensity, in which case the device will behave in its default manner.

fadein:
+ +
If true, target lights will not turn on instantly but fade-in smoothly instead. if false, target lights will be turned on without the fading effect.
+ +

Note: All devices might not support fade-in, in which case the device will behave in its default manner.

Return value:

This method does not return a value.

Remarks:

Switching and keeping the mobile device lights on consumes energy. Therefore, it is recommended that you carefully consider the need for using the lights.

Example code:

function callLightOn()
+{
+   // get the Embed element reference
+   var sysinfo = document.embeds[0];
+   /*********************
+   call lighton() method, which turns on the light 
+   of all displays and keyboard with the maximum duration 
+   and using the default light intensity with the fade-in 
+   effect
+   *********************/
+   var target =  sysinfo.lighttargetsystem;
+   var duration = sysinfo.lightmaxduration;
+   var intensity = sysinfo.lightdefaultintensity;
+   sysinfo.lighton(target, duration, intensity, true);
+}