B4A Library ECS/POS printer WIFI print library

THIS libary can print string ,and picture ,

same to USB print libary,only can use for ECS/POS printer,
the other printer i guess can use
.SendDataByte() function send different data format by byte.i didn't try it.
i have try this demo can make a sleep HP printer wake up,but didn't print.


https://www.b4x.com/android/forum/threads/ecs-pos-printer-usb-print-library.87122/

 

[IdasI4A]

I'm trying to use your library and when I'm going to run the example it gives me the following error:

--------- beginning of /dev/log/main
** Service (starter) Destroy **
--------- beginning of /dev/log/system
PackageAdded: package:epson.print
Connected to B4A-Bridge (Wifi)
Installing file.
PackageAdded: package:b4a.example
*** Service (starter) Create ***
** Service (starter) Start **
main_globals (B4A line: 20)
End Sub
java.lang.VerifyError: cn/com/zj/zjwfprinter/PrintDemo
at b4a.example.main._globals(main.java:488)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:186)
at b4a.example.main.initializeGlobals(main.java:313)
at b4a.example.main.afterFirstLayout(main.java:99)
at b4a.example.main.access$000(main.java:17)
at b4a.example.main$WaitForLayout.run(main.java:80)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5001)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:787)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:603)
at dalvik.system.NativeStart.main(Native Method)

Can you help me.
Thank you.

 

[hears]

I'm trying to use your library and when I'm going to run the example it gives me the following error:

Can you help me.
Thank you.

first press connect button,after print.
when i first press print,have same erro.

have you change IP address for your printer ?

 

[Dadaista]

If it could print on a usb printer connected to a router, it would be a hit

 

[IdasI4A]

first press connect button,after print.
when i first press print,have same erro.

have you change IP address for your printer ?

The error is given before nothing appears on the screen.
The buttons do not appear.

 

[hears]

The error is given before nothing appears on the screen.
The buttons do not appear.

i have tried,here have no erro .maybe because B4A version or IDE setting
sdk i use
android-sdk\platforms\android-22\android.jar
javac i use :
Java\jdk1.8.0_111\bin\javac.exe

my b4a version is 7.8

 

[IdasI4A]

Thank you very much for your answers.
I was reviewing the paths and the Android version, and discovered that the problem was the Android version.

• With Android 4.4 the error occurred.
• With Android 5.1 the buttons appear.

Now I press the "Connect" button and then I press the "PRINT STRING" button and I get the following error:

main_button2_click (B4A line: 62)
pt.printstring("Hola Mundo")
java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.net.Socket.isConnected()' on a null object reference
at com.zj.wfsdk.WifiCommunication.sndByte(WifiCommunication.java:88)
at cn.com.zj.zjwfprinter.PrintDemo.printstring(PrintDemo.java:1090)
at b4a.example.main._button2_click(main.java:458)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:186)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:170)
at anywheresoftware.b4a.BA.raiseEvent(BA.java:166)
at anywheresoftware.b4a.objects.ViewWrapper$1.onClick(ViewWrapper.java:80)
at android.view.View.performClick(View.java:4780)
at android.view.View$PerformClick.run(View.java:19866)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5254)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:935)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:730)

You can keep helping me.
Thank you.

 

[hears]

didn't connect success,
first make sure your andriod device can success PING your printer.
second,the print must be a EPSON chip pos printer

AND have you change the IP address in code, to your printer IP?