Generic type cannot be used

[merlinJeyakumar]

How to use generic type

abstract class BaseActivity<B : ViewDataBinding, VM : BaseViewModel>( private val bindingFactory: Int, private val viewModelClass: Class, ) : AppCompatActivity() {

protected val binding: B by viewBinding()

}

[kirich1409]

It's not possible. To create an instance the delegate needs to now ViewBinding class.

[kirich1409]

The delegate few creation variants and one of them has ViewModel class as parameter or even you can pass function where you will create an instance of ViewBinding

[kirich1409]

https://github.com/androidbroadcast/ViewBindingPropertyDelegate/blob/master/vbpd/vbpd-full/src/main/java/by/kirich1409/viewbindingdelegate/ActivityViewBindings.kt 37 line

[merlinJeyakumar]

    @LayoutRes private val layoutRes: Int,
) {

    private var binding: T? = null

    operator fun getValue(activity: R, property: KProperty<*>): T {
        if (binding == null) {
            binding = DataBindingUtil.setContentView<T>(activity, layoutRes).apply {
                lifecycleOwner = activity
            }
        }
        return binding!!
    }
}

fun <R : AppCompatActivity, T : ViewDataBinding> contentView(
    @LayoutRes layoutRes: Int,
): ContentViewBindingDelegate<R, T> = ContentViewBindingDelegate(layoutRes)

I have created and using this extension function, while using it with navigation view it causing crash NavHost.context() null pointer

[merlinJeyakumar]

its working fine for my baseclass,

you can close this ticket, Problem is I called lifecycle binding before activity creation