使用kotlin委托实现ViewBinding懒加载

fun <T : ViewBinding> AppCompatActivity.binding(inflate: (LayoutInflater) -> T): Lazy<T> {
    return MainLazy(this, inflate)
}
class MainLazy<T : ViewBinding>(
    val activity: AppCompatActivity,
    val inflate: (LayoutInflater) -> T
) : Lazy<T> {
    var cache: T? = null
    override val value: T
        get() {
            if (cache == null) {
                cache = inflate(activity.layoutInflater)
            }
            return cache!!
        }
    override fun isInitialized(): Boolean = cache != null
}
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val binding: ActivityMainBinding by binding(ActivityMainBinding::inflate)
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fun <T : ViewBinding> AppCompatActivity.bindingByLazy(inflate: (LayoutInflater) -> T)= lazy {
     inflate(layoutInflater).apply {
    }
}
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val binding: ActivityMainBinding by bindingByLazy(ActivityMainBinding::inflate)
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