                          _ selector: Selector? = nil) {
         
         wasChanged = true
+        sectionWasChanged()
         
         for source in sources {
             self.addOnTop(source, target: target, selector)

    public func delete(_ source: ImoTableViewSource) throws {
        
        wasChanged = true
        sources.remove(at: try indexOfSource(source: source))
    }
    

                         _ selector: Selector? = nil) {
        
        wasChanged = true
        sectionWasChanged()
        
        if let target = target {
            source.target = target
