Question

每次创建片段实例并在按下时重新加载。

如何克服这个问题？

在nav控制器中没有适当的后堆栈是一个巨大的生产力问题。希望它是一项缺少的功能或有针对性的解决方法... IMO这是必须的，必须尽早引入，而不是稍后引入（但是：https://issuetracker.google.com/issues/109856764说，我们不会允许在可预见的将来定制交易类型（例如隐藏/显示等）。）：（

Nav-Framework is nice, however, it create fragment's view every time

有人可以解决吗？

我的代码是使用导航

进行导航

object NavigationHelper : Navigational {


override fun moveDownWithPop(view: View,id: Int,popStackId: Int) {
    Navigation.findNavController(view).navigate(id,
            null,
            NavOptions.Builder()
                    .setPopUpTo(popStackId,
                            true).build()
    )
}

override fun moveDownWithDataPop(view: View,id: Int,popStackId: Int,bundle : Bundle) {
    Navigation.findNavController(view).navigate(id,
            bundle,
            NavOptions.Builder()
                    .setPopUpTo(popStackId,
                            true).build()
    )
}

override fun moveUp(view: View) {
    Navigation.findNavController(view).navigateUp()
}

override fun moveDown(view: View,id: Int) {
    Navigation.findNavController(view).navigate(id)
}

override fun moveDown(view: View,id: Int,args : Bundle) {
    Navigation.findNavController(view).navigate(id,args)
}

fun navigateGraph(graphId : Int,context : Context){
    var finalHost: NavHostFragment?  = NavHostFragment.create(graphId)
    (context as MainActivity).supportFragmentManager.beginTransaction()
            .replace(com.admision.R.id.content,finalHost!!)
            .setPrimaryNavigationFragment(finalHost) // this is the equivalent to app:defaultNavHost="true"
            .commit()
}
}

我找到了一个博客Why I Will Not Use Architecture Navigation Component

Answer 1

就像Bhavesh所做的一样，在我的情况下，我只有一个列表，而onCreateView中的这一行对我来说足够了：

if (adapter.isEmpty()) {
            viewModel.getShopCats()
}

和适配器只需要具有以下内容：

fun isEmpty(): Boolean {
        return modelList.isNullOrEmpty()
}

体系结构导航组件：每次都会调用onCreateView

1 个答案: