Android 数据绑定在自定义视图中注入 ViewModel

Question

我将离开这个 Whosebug 答案将数据对象绑定到自定义视图。但是，在设置完所有内容后，我的视图并未使用数据进行更新，而是 TextView 保持空白。这是我的代码（经过简化，为了适合这里）：

activity_profile.xml:

<layout xmlns...>
    <data>
        <variable name="viewModel" type="com.example.ProfileViewModel"/>
    </data>
    <com.example.MyProfileCustomView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:viewModel="@{viewModel}">
</layout>

view_profile.xml:

<layout xmlns...>
    <data>
        <variable name="viewModel" type="com.example.ProfileViewModel"/>
    </data>
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@{viewModel.name}">
</layout>

MyProfileCustomView.kt:

class MyProfileCustomView : FrameLayout {
    constructor...

    private val binding: ViewProfileBinding = ViewProfileBinding.inflate(LayoutInflater.from(context), this, true)

    fun setViewModel(profileViewModel: ProfileViewModel) {
        binding.viewModel = profileViewModel
    }
}

ProfileViewModel.kt:

class ProfileViewModel(application: Application) : BaseViewModel(application) {
    val name = MutableLiveData<String>()

    init {
        profileManager.profile()
            .observeOn(AndroidSchedulers.mainThread())
            .subscribe(::onProfileSuccess, Timber::d)
    }

    fun onProfileSuccess(profile: Profile) {
        name.postValue(profile.name)
    }
}

一切正常，对 profileManager.profile() 的 API 调用成功，ViewProfileBinding class 使用正确的设置成功创建。问题是当我执行 name.postValue(profile.name) 时，视图未更新为 profile.name

的值

Answer 1

缺的一块是设置一个Lifecycle Owner.

binding.setLifecycleOwner(parent) //parent should be a fragment or an activity

Answer 2

回答对我有帮助，想抛出一个 util 方法，您可以添加该方法以获取 LifeCycleOwner

fun getLifeCycleOwner(view: View): LifecycleOwner? {
    var context = view.context

    while (context is ContextWrapper) {
        if (context is LifecycleOwner) {
            return context
        }
        context = context.baseContext
    }

    return null
}

在您看来：

getLifeCycleOwner(this)?.let{
   binding.setLifecycleOwner(it)
}

Android 数据绑定在自定义视图中注入 ViewModel

Android data binding inject ViewModel in custom view

data-binding

android

android-custom-view

kotlin

android-viewmodel