Display Manager

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EMDK For Xamarin - 4.0

Overview

The Display Manager (DisplayMgr) provides control of certain display screen features on the device.

Main Functionality

  • Enable/disable:
    • Screen shot usage
    • Stay Awake mode
    • Screen blanking
  • Set the display screen timeout interval
  • Set the screen blanking signal port
  • Set the screen blanking signal polarity
  • Set the screen blanking signal debounce delay

Screen Shot Enable/Disable

Controls whether a device can use Android's built-in screen capture capability, which captures the contents of the screen and saves it to a file on the device.

Note: The method of capturing the screen generally involves a combination of simultaneous key presses that varies from one device to another.

Parm Name: ScreenShotUsage

Option Name Description Note Requires
0 Do Nothing This value (or the absence of this parm from the XML) causes no change to the current behavior; any previously selected setting is retained.

OSX: 3.6,4.5 ONLY

NOT IN OSX: 4.0 - 4.4

MX: 5.0+

1 Enable Enables the ability to use the Android screen capture feature.

OSX: 3.6,4.5 ONLY

NOT IN OSX: 4.0 - 4.4

MX: 5.0+

2 Disable Disables the ability to use the Android screen capture feature.

OSX: 3.6,4.5 ONLY

NOT IN OSX: 4.0 - 4.4

MX: 5.0+

Stay Awake Enable/Disable

Controls whether a device enters suspend (sleep) mode based on its connection to an external power source. Device otherwise operates according to settings in the Developer Options section of the Android Settings panel. Note: This feature is enabled by default on Zebra VC80x vehicle computers.

Parm Name: StayAwake

Option Name Description Note Requires
0 Do Nothing This value (or the absence of this parm from the XML) will cause no change to the current behavior; any previously selected setting will be retained.

MX: 7.2+

Android API: 17+

1 Enable Prevents the device from entering suspend (sleep) mode when it is connected to an external power source.

MX: 7.2+

Android API: 17+

2 Disable Allows the device to enter suspend (sleep) mode regardless of its connection to an external power source.

MX: 7.2+

Android API: 17+

Set Screen Timeout Interval

Used to set the length of time the device waits during periods of inactivity (without screen touches or key presses) before turning off the screen to conserve power. Ideally, this interval should represent a balance between battery preservation and user convenience.

Note: Android supports only the display-screen timeout settings shown in the table below. Specifying a value between any two supported values will change the setting to the closest supported value. Specifying a value outside the minimum or maximum shown causes an error in the Result XML document and the setting change is ignored.

Parm Name: TimeoutInterval

Option Name Description Note Requires
0 Do not change This value (or the absence of this parm from the XML) causes no change to the current display screen timeout interval; any previously selected setting is retained.

MX: 4.3+

Android API: 1+

15 15 seconds after Display Timeout Causes the display screen to timeout after 15 seconds of device-user inaction.

MX: 4.3+

Android API: 1+

30 30 seconds after Display Timeout Causes the display screen to timeout after 30 seconds of device-user inaction.

MX: 4.3+

Android API: 1+

60 1 minute after Display Timeout Causes the display screen to timeout after one minute of device-user inaction.

MX: 4.3+

Android API: 1+

120 2 minutes after Display Timeout Causes the display screen to timeout after two minutes of device-user inaction.

MX: 4.3+

Android API: 1+

300 5 minutes after Display Timeout Causes the display screen to timeout after five minutes of device-user inaction.

MX: 4.3+

Android API: 1+

600 10 minutes after Display Timeout Causes the display screen to timeout after 10 minutes of device-user inaction.

MX: 4.3+

Android API: 1+

1800 30 minutes after Display Timeout Causes the display screen to timeout after 30 minutes of device-user inaction.

MX: 4.3+

Android API: 1+

65535 Never Keeps the display screen on at all times despite any period of device-user inaction.

MX: 9.2+

Android API: 1+

Screen Blanking Enable/Disable

Controls whether a device display can be made blank when triggered by the signal set in the Screen Blanking Signal parameter. Blanking the screen blocks all user interaction with the device and its apps.

This feature was developed for safety reasons and is intended for use with vehicle-mount computers while the vehicle is in motion. It can be activated, for example, by an electrical signal wired to the vehicle accelerator. For more information about connecting a Zebra device to vehicle wiring, please refer to the Integrator Guide that accommpanied the unit.

Parm Name: ScreenBlanking

Option Name Description Note Requires
0 Do Nothing This value (or the absence of this parm from the XML) will cause no change to the current behavior; any previously selected setting will be retained.

MX: 7.1+

1 Never blanked Prevents blanking of the screen.

MX: 7.1+

2 When Triggered by Signal Enables the screen to be blanked when triggered by a signal external to the device.

MX: 7.1+

Set Screen Blanking Signal

Used to specify which external signal will control Screen Blanking, if enabled. Inputs 1 and 2 correspond to serial ports 1 and 2 on the Zebra VC80x vehicle-mounted computer. Other devices might differ. The serial port can be used to determine whether the vehicle’s accelerator pedal is pressed. For more information about connecting a Zebra device to vehicle wiring, please refer to the Integrator Guide that accommpanied the unit.

Parm Name: ScreenBlankingSignal

Option Name Description Note Requires
1 Input 1 Sets the screen blanking signal to Input 1 (VC80x serial port 1).

MX: 7.1+

2 Input 2 Sets the screen blanking signal to Input 2 (VC80x serial port 2).

MX: 7.1+

Set Blanking Signal Polarity

Controls whether to blank the screen when the signal designated in the Screen Blank Signal parameter is present or absent.

Parm Name: ScreenBlankingSignalPolarity

Option Name Description Note Requires
1 Blank screen when vehicle goes active (ON) Sets the screen to go blank when a signal is present.

MX: 7.1+

2 Blank screen when vehicle goes inactive (OFF) Sets the screen to go blank when a signal is absent.

MX: 7.1+

Set Blanking Debounce Delay

Used to specify a delay (in ms) after a signal change is detected before blanking or unblanking the screen. Default value is 1000 ms (one second).

Parm value input rules:

  • Accepts an integer from 250-32767
  • If no value is entered, default value of 1000 will be used

Parm Name: ScreenBlankingDebounceDelay

Requires:

  • MX: 7.1+

Font Size

used to select the size of alpha-numeric characters for all UI elements displayed on the device screen.

Parm Name: FontSize

Option Name Description Note Requires
0 Do Nothing This value (or the absence of this parm from the XML) causes no change to the current behavior; any previously selected setting is retained.

MX: 9.2+

0.85 Small Sets the font to one size smaller than the Android default size.

MX: 9.2+

1 Default Sets the font to the Android default size.

MX: 9.2+

1.15 Large Sets the font to one size larger than the Android default size.

MX: 9.2+

1.3 Largest Sets the font to two sizes larger than the Android default size.

MX: 9.2+

Display Size

Used to select the size of UI elements displayed on the device.

Parm Name: DisplaySize

Option Name Description Note Requires
0 Do Nothing This value (or the absence of this parm from the XML) causes no change to the current behavior; any previously selected setting is retained.

MX: 9.2+

Android API: 27+

SMALL Small Sets the size of UI elements at one step smaller than Android default size.

MX: 9.2+

Android API: 27+

DEFAULT Default Sets the Android default size for UI elements.

MX: 9.2+

Android API: 27+

LARGE Large Sets the size of UI elements at one step larger than Android default size.

MX: 9.2+

Android API: 27+

LARGER Larger Sets the size of UI elements at two steps larger than Android default size.

MX: 9.2+

Android API: 27+

LARGEST Largest Sets the size of UI elements at three steps larger than Android default size.

MX: 9.2+

Android API: 27+

Examples

Turn On Screen Blanking

The sample below turns on the screen-blanking feature, selects serial port 1 on the Zebra VC80x vehicle-mounted computer as the signal port with standard-polarity wiring, and sets a two second (2000 ms) delay.

<wap-provisioningdoc>
    <characteristic type="DisplayMgr">
        <parm name="ScreenBlanking" value="2" />
        <characteristic type="screen-blanking-details">
            <parm name="ScreenBlankingSignal" value="1" />
            <parm name="ScreenBlankingPolarity" value="1" />
            <parm name="ScreenBlankingDebounceDelay" value="2000" />
        </characteristic>
    </characteristic>
</wap-provisioningdoc>

Turn Off Screen Blanking

<wap-provisioningdoc>
    <characteristic type="DisplayMgr">
        <parm name="ScreenBlanking" value="1" />
    </characteristic>
</wap-provisioningdoc>

Turn off the stay-awake feature

<wap-provisioningdoc>
    ​<characteristic type="DisplayMgr">
        ​​<parm name="StayAwake" value="2" />
    ​</characteristic>
</wap-provisioningdoc>