B4J Question ParseHexToFloat

Declan

Well-Known Member
Licensed User
Longtime User
Hi, I am trying to parse the data as follows:
B4X:
' Input Data (cFrame) HEX = 53193315451c0a2d2a410000
    Dim GEOLat As String
    Dim GEOLon As String

GEOLat = cFrame.SubString2(2,8)
GEOLon = cFrame.SubString2(10,16)
GEOLat = ParseHexToFloat(GEOLat)
GEOLon = ParseHexToFloat(GEOLon)

B4X:
Sub ParseHexToFloat(hex As String) As Float
    Dim BC As ByteConverter
    Return BC.FloatsFromBytes(BC.HexToBytes(hex))(0) '<<---Error
End Sub

I Receive the following Error:
B4X:
Error occurred on line: 103
java.lang.ArrayIndexOutOfBoundsException
    at java.lang.reflect.Array.get(Native Method)
    at anywheresoftware.b4a.shell.ArraysUtils.getElement(ArraysUtils.java:76)
    at anywheresoftware.b4a.shell.Shell.getArrayElement(Shell.java:471)
    at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:263)
    at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:159)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at anywheresoftware.b4a.BA.raiseEvent2(BA.java:90)
    at anywheresoftware.b4a.ShellBA.raiseEvent2(ShellBA.java:93)
    at anywheresoftware.b4a.debug.Debug.delegate(Debug.java:61)
    at b4j.example.sigfox._hnsconvertreturn(sigfox.java:223)
    at b4j.example.sigfox._handle(sigfox.java:206)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at anywheresoftware.b4a.shell.Shell.runMethod(Shell.java:614)
    at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:231)
    at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:159)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at anywheresoftware.b4a.BA.raiseEvent2(BA.java:90)
    at anywheresoftware.b4a.ShellBA.raiseEvent2(ShellBA.java:93)
    at anywheresoftware.b4a.BA.raiseEvent(BA.java:77)
    at anywheresoftware.b4j.object.JServlet$Handle.run(JServlet.java:130)
    at anywheresoftware.b4a.keywords.SimpleMessageLoop.runMessageLoop(SimpleMessageLoop.java:30)
    at anywheresoftware.b4a.StandardBA.startMessageLoop(StandardBA.java:26)
    at anywheresoftware.b4a.ShellBA.startMessageLoop(ShellBA.java:114)
    at anywheresoftware.b4a.keywords.Common.StartMessageLoop(Common.java:146)
    at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:303)
    at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:159)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at anywheresoftware.b4a.BA.raiseEvent2(BA.java:90)
    at anywheresoftware.b4a.ShellBA.raiseEvent2(ShellBA.java:93)
    at anywheresoftware.b4a.BA.raiseEvent(BA.java:77)
    at b4j.example.main.main(main.java:29)
 

Daestrum

Well-Known Member
Licensed User
Longtime User
Think you need to help the compiler determine what the string represents
Try
B4X:
GEOLat = "0x" & cFrame.SubString2(2,8)
GEOLon = "0x" & cFrame.SubString2(10,16)
 
Upvote 0

stevel05

Expert
Licensed User
Longtime User
A float should be represented as 4 bytes, you are only passing 3.
 
Upvote 0
Top