I am contacting the author Erel. I got this error in Crashlytics.
Crashlytics:
Fatal Exception: java.lang.IllegalArgumentException: width and height must be > 0
at android.graphics.Bitmap.createBitmap(Bitmap.java:1113)
at android.graphics.Bitmap.createBitmap(Bitmap.java:1080)
at android.graphics.Bitmap.createBitmap(Bitmap.java:1030)
at android.graphics.Bitmap.createBitmap(Bitmap.java:991)
at anywheresoftware.b4a.objects.drawable.CanvasWrapper.Initialize(CanvasWrapper.java:81)
at anywheresoftware.b4a.objects.B4XCanvas.Initialize(B4XCanvas.java:54)
at cz.flashcards3000.clvswipe._initialize(clvswipe.java:314)
at cz.flashcards3000.pmarked._b4xpage_created(pmarked.java:73)
at cz.flashcards3000.pmarked.callSub(pmarked.java:473)
at anywheresoftware.b4a.keywords.Common.CallSub4(Common.java:1098)
at anywheresoftware.b4a.keywords.Common.CallSubNew2(Common.java:1069)
at cz.flashcards3000.b4xpagesmanager._createpageifneeded(b4xpagesmanager.java:536)
at cz.flashcards3000.b4xpagesmanager._showpage(b4xpagesmanager.java:873)
at cz.flashcards3000.b4xpages._showpage(b4xpages.java:128)
at cz.flashcards3000.b4xmainpage._bntmarked_click(b4xmainpage.java:358)
at java.lang.reflect.Method.invokeNative(Method.java)
at java.lang.reflect.Method.invoke(Method.java:423)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:221)
at anywheresoftware.b4a.BA.raiseEvent(BA.java:201)
at anywheresoftware.b4a.objects.ViewWrapper$1.onClick(ViewWrapper.java:80)
at android.view.View.performClick(View.java:7448)
at android.view.View.performClickInternal(View.java:7425)
at android.view.View.access$3600(View.java:810)
at android.view.View$PerformClick.run(View.java:28309)
at android.os.Handler.handleCallback(Handler.java:938)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:223)
at android.app.ActivityThread.main(ActivityThread.java:7680)
at java.lang.reflect.Method.invokeNative(Method.java)
at java.lang.reflect.Method.invoke(Method.java:423)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)