Dim no As NativeObject = B4XFloatTextField1.TextField
Dim layers As List = no.RunMethod("layer.sublayers", Null)
For Each layer As NativeObject In layers
    Dim layerName As String = layer.RunMethod("className", Null)
    If layerName.Contains("CALayer") Then
        layer.RunMethod("removeFromSuperlayer", Null)
    End If
Next