I am trying to use the ZXing Scanner library with B4X Page and it generates the following error:
The error code
Important !! If I use the library in a project that does not use B4XPage it works correctly
B4X:
Sub Class_Globals
Private Root As B4XView 'ignore
Private xui As XUI 'ignore
Private zx1 As BarcodeScanner
Private pmain As Panel
Private b1 As Button
Private b2 As Button
Private b3 As Button
Private b4 As Button
Private b5 As Button
Private lResult As Label
Private lAuto As Label
Private l3 As Label
Private view As Panel
Private flag As Int = 0
Private runningavg As Int = 127
Private scanStarted As Boolean = False
End Sub
'You can add more parameters here.
Public Sub Initialize
End Sub
'This event will be called once, before the page becomes visible.
Private Sub B4XPage_Created (Root1 As B4XView)
Root = Root1
'load the layout to Root
End Sub
Private Sub B4XPage_Appear
Root.LoadLayout("scanner")
lResult.Text = "Result"
lAuto.Text = ""
b4.Text = "+"
b4.TextSize = 20
b5.Text = "-"
b5.TextSize = 20
CreateScanner
End Sub
'You can see the list of page related events in the B4XPagesManager object. The event name is B4XPage.
Private Sub CreateScanner
Dim rp As RuntimePermissions
Dim Result As Boolean = True
If Not(rp.Check(rp.PERMISSION_CAMERA)) Then
rp.CheckAndRequest(rp.PERMISSION_CAMERA)
Wait For Activity_PermissionResult (Permission As String, Result As Boolean)
End If
If Result Then
Dim x, y, w, h As Int
x = 20
y = 220
w = 640
h = 420
view.Initialize("")
Root.Color = Colors.White
pmain.AddView(view, x, y, w, h)
zx1.Initialize("zx1") <----------------------------------------------HERE ERROR
zx1.LaserColor = Colors.Green
zx1.MaskColor = Colors.ARGB(150, 0, 0, 200)
zx1.BorderColor = Colors.Magenta
zx1.BorderStrokeWidth = 5
zx1.BorderLineLength = 40
zx1.Beep = True
zx1.Vibrate = True
zx1.AutoFocusInterval = 500
zx1.AutoFocus = True
zx1.FocusMode = zx1.FOCUS_MODE_AUTO
zx1.AddPanel(view)
l3.Text = zx1.Width & "/" & zx1.Left
Log($"Camera is : ${zx1.checkCameraHardware} "$)
Else
ToastMessageShow("Permission not granted", True)
End If
End Sub
Sub b1_Click
zx1.ToggleFlash
End Sub
Sub b2_Click
zx1.Visible = True
zx1.startScanner
' zx1.TurnFlashOn
' Log(zx1.isFlashOn)
scanStarted = True
b2.Enabled = False
b1.Enabled = True
End Sub
Sub b3_Click
zx1.Visible = False
zx1.stopScanner
lResult.Text = ""
lAuto.Text = ""
l3.Text = ""
scanStarted = False
b2.Enabled = True
b1.Enabled = False
End Sub
Sub b4_Click
Log("Zoom b4")
Dim zoomInValue As Int = 5 'positive values -> zoon in
If scanStarted Then
If zx1.CurrentZoomValue <= (zx1.MaxZoomValue - zoomInValue) Then
zx1.zoomIn(zoomInValue)
Else
zx1.zoomIn(zx1.MaxZoomValue - zx1.CurrentZoomValue)
End If
Log("Zoom +")
End If
End Sub
Sub b5_Click
Log("Zoom b5")
Dim zoomInValue As Int = -5 'negative values -> zoom out
If scanStarted Then
If zx1.CurrentZoomValue > (-1* zoomInValue) Then
zx1.zoomIn(zoomInValue)
Else
zx1.zoomIn(0 - zx1.CurrentZoomValue)
End If
Log("Zoom -")
End If
End Sub
Sub zx1_scan_result (scantext As String, scanformat As String)
' Dim tim As Long = 100
Log ("B4A scan text = " & scantext)
Log ("B4A scan format = " & scanformat)
' Log("isFlashOn = " & zx1.isFlashOn)
lResult.Text = "Text : " & scantext & CRLF & " Format : " & scanformat
ToastMessageShow("Text : " & scantext & CRLF & " Format : " & scanformat, True)
zx1.Visible = False
zx1.stopScanner
scanStarted = False
End Sub
Sub zx1_brightness_changed (bright As Int ) 'ADDED 6 MARCH 2016
' Log("bright = " & bright) 'this is the average brightness of the frame that was captured for possible barcode extraction
flag = flag + 1
lAuto.Text = "Brigtness = " & bright
If flag = 30 Then 'I only want to use the average brightness of every 30th frame to calculate a running brigtness average
flag = 0 'reset the count to zero for the next 30 frames
If bright < 150 Then 'discard excessive high brigness values
runningavg = (runningavg + bright) / 2
' Log("runningavg brightness = " & runningavg)
If runningavg < 70 Then
If zx1.isFlashOn = False Then zx1.TurnFlashOn
Else if runningavg > 115 Then
If zx1.isFlashOn = True Then zx1.TurnFlashOff
End If
End If
End If
' l3.Text = "isFlashOn = " & zx1.isFlashOn
End Sub
Sub B4XPage_Foreground
If zx1.Autofocus = True Then
lAuto.Text = "AUTO : ON"
Else
lAuto.Text = "AUTO : OFF"
End If
zx1.Visible = True
zx1.Autofocus = True
zx1.startScanner
End Sub
Sub B4XPage_Background
zx1.Visible = False
zx1.stopScanner
End SubThe error code
B4X:
Copying updated assets files (1)
*** Service (starter) Create ***
** Service (starter) Start **
** Activity (main) Create, isFirst = true **
Call B4XPages.GetManager.LogEvents = True to enable logging B4XPages events.
** Activity (main) Resume **
Error occurred on line: 77 (B4XPage2)
android.content.res.Resources$NotFoundException: Resource ID #0x0
at android.content.res.Resources.getValue(Resources.java:1266)
at android.content.res.Resources.getColor(Resources.java:920)
at com.scanner.core.ViewFinderView.<init>(ViewFinderView.java:38)
at com.scanner.core.BarcodeScannerView.createViewFinderView(BarcodeScannerView.java:129)
at com.scanner.core.BarcodeScannerView.<init>(BarcodeScannerView.java:29)
at com.scanner.zxing.ZXingScannerView.<init>(ZXingScannerView.java:70)
at com.scanner.ScannerWrapper._initialize(ScannerWrapper.java:82)
at com.scanner.ScannerWrapper.Initialize(ScannerWrapper.java:71)
at b4a.example.b4xpage2$ResumableSub_CreateScanner.resume(b4xpage2.java:330)
at b4a.example.b4xpage2._createscanner(b4xpage2.java:220)
at b4a.example.b4xpage2._b4xpage_appear(b4xpage2.java:210)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at anywheresoftware.b4a.shell.Shell.runMethod(Shell.java:732)
at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:351)
at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:255)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at anywheresoftware.b4a.ShellBA.raiseEvent2(ShellBA.java:144)
at anywheresoftware.b4a.BA$2.run(BA.java:387)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5254)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:902)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:697)
** Activity (main) Pause event (activity is not paused). **Important !! If I use the library in a project that does not use B4XPage it works correctly
Last edited:
