ZebraLink SDK intermittent connectivity or connection freezes

Article ID: 37496112



Topic or Information

 This solution is useful for:

  • Users experiencing intermittent connectivity with the ZebraLink SDK
  • Users experiencing freezing after specific function calls 


Applies To

ZebraLink SDK
Zebra Mobile Printers Except ZQ110, EM Series

Excludes: 2824 Series, 2844 Series, S4M (E53 Firmware Version), 888 DD/TT Series, MZ Series, ZQ110, EM220, EM220II, All Kiosk (except KR403)


The ZebraLink SDK for mobile devices (Android, Blackberry, iOS, Windows CE/Mobile) may demonstrate semi-consistent freezes or intermittent connectivity during the execution of an application.  This behavior may or may not be directly related to specific and repeatable conditions, therefore potentially appearing at random intervals.  While this solution is not all encompassing, it provides users with known issues that have caused these symptoms before.  Check for the following if you are experiencing the symptoms:

  • Use of ZebraPrinterFactory's method getInstance: This method can cause an unknown language exception to be thrown especially with older printer firmware and older SDK versions.  Try to avoid using this method if possible.  As a workaround, create a ZebraPrinter object directly instead of calling this getInstance
  • Use of the graphic utility's printImage method that calls a bitmap object as a parameter:  This method has caused applications to freeze in very specific conditions.  It is encouraged to use the alternative printImage method that passes a file path as a parameter.  See the SDK documentation for specific details on implementing this alternate method. 
  • Successive and immediate calls to similar methods can cause the SDK to stop responding:  It is generally encouraged to leave ample time in between function calls that initiate communication with the printer.  For example - repeated calls to open and close a connection to a printer should be padded with a three to four second wait time in between. 
  • Radio frequency interference: while not common, it is possible that nearby equipment using radio signals at similar frequencies could be interfering with the device in question.  If it is possible that surrounding equipment could be interfering with the device, try to run the setup in an area without the radio traffic.

+ Product Codes

  • 105SLPlus Industrial Printers
  • 105SLPlus Industrial Printers
  • 110PAX Print Engines (disc.)
  • 110Xi4 Industrial Printer
  • 140Xi4 Industrial Printer
  • 170Xi4 Industrial Printer
  • 220Xi4 Industrial Printer
  • 2824 Plus Series
  • 2824-Z Series
  • All Surface RFID Label Solution
  • Desktop Printers
  • G-Series GC Desktop Printers
  • G-Series GK Desktop Printers
  • G-Series GX Desktop Printers
  • GC420d Desktop Printer
  • GC420t Desktop Printer
  • GK420 Healthcare Desktop Printers
  • GK420d Desktop Printer
  • GK420d Healthcare Desktop Printer
  • GK420t Desktop Printer
  • GK420t Healthcare Desktop Printer
  • GT800 Desktop Printer
  • GX420Rx Desktop Printer
  • GX420d Desktop Printer
  • GX420t Desktop Printer
  • GX430d Desktop Printer
  • GX430t Desktop Printer
  • Industrial Printers
  • KR403 Kiosk Receipt Printer
  • LP 2824 Plus Desktop Printer
  • Link-OS Multiplatform SDK
  • Mobile Printers
  • P4T Mobile Printers
  • P4T Mobile Printers
  • Print Engines
  • QL Series Mobile Printers
  • QL320 Mobile Printer
  • QL420 Mobile Printer
  • QLn Series Healthcare Mobile Printers
  • QLn Series Mobile Printers
  • QLn220 Healthcare
  • QLn220 Mobile Printer
  • QLn320 Healthcare
  • QLn320 Mobile Printer
  • QLn420 Mobile Printer
  • R110Xi4 RFID Printer
  • RFID Printers
  • RP4T RFID Printers
  • RP4T RFID Printers
  • RW 220 Mobile Printer
  • RW 420 Mobile Printer
  • RW 420 Print Station
  • RW Series Mobile Printers
  • TLP 2824Plus Desktop Printer
  • Xi Series Industrial Printers
  • ZD410 Series
  • ZD410D
  • ZD420 Series
  • ZD420-HC
  • ZD420C
  • ZD500 Desktop Printer
  • ZD500 Desktop Printer
  • ZD500R RFID Printers
  • ZD500R RFID Printers
  • ZE500 Print Engines
  • ZE500 Print Engines
  • ZE500R RFID Print Engine
  • ZE500R RFID Print Engine
  • ZM400
  • ZM600
  • ZQ500 Series Mobile Printers
  • ZQ510 Mobile Printer
  • ZQ520 Mobile Printer
  • ZR300 Series Mobile Printers
  • ZR338 Mobile Printers
  • ZR600 Series Healthcare Mobile Printers
  • ZR600 Series Mobile Printers
  • ZT200 Series Industrial Printers
  • ZT210 Industrial Printer
  • ZT220 Industrial Printer
  • ZT230 Industrial Printer
  • ZT400 Series Industrial Printers
  • ZT400 Series RFID Printers
  • ZT410 Industrial Printer
  • ZT410 RFID Industrial Printer
  • ZT420 Industrial Printer
  • ZT420 RFID Industrial Printer
  • iMZ Series Mobile Printers
  • iMZ220 Mobile Printer
  • iMZ320 Mobile Printer