Question

我在通过viewModel（+ dataBinding inside）向我的editText字段添加错误时遇到问题这是我的活动：类RegisterActivity：BaseActivityFullscreen（）{

var binding: ActivityRegisterBinding? = null
var viewmodel: RegisterViewModel? = null

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    binding = DataBindingUtil.setContentView(this, tv.hotpot.luve.R.layout.activity_register)
    viewmodel = ViewModelProviders.of(this).get(RegisterViewModel::class.java)
    binding?.viewmodel = viewmodel
}

这是我要在其中添加错误的editText：

<EditText
                android:hint="@string/email_address"
                android:text="@={viewmodel.email}"
                android:onTextChanged="@{viewmodel::onEmailChanged}"
                android:layout_width="342dp"
                android:backgroundTint="#40FFFFFF"
                android:textColorHint="#99FFFFFF"
                android:layout_height="wrap_content"
                android:inputType="textEmailAddress"
                android:ems="10"
                android:id="@+id/email_address"
                android:textColor="@android:color/white"
                android:selectAllOnFocus="true" android:gravity="center" android:textSize="16sp"
                android:layout_marginStart="8dp" app:layout_constraintStart_toStartOf="parent"
                android:layout_marginLeft="8dp" android:layout_marginEnd="8dp" app:layout_constraintEnd_toEndOf="parent"
                android:layout_marginRight="8dp"
                android:paddingBottom="24dp"
                android:layout_marginTop="50dp" app:layout_constraintTop_toTopOf="@+id/password"/>

这是viewModel：

class RegisterViewModel : ViewModel() {
    private val parentJob = Job()

    private val coroutineContext: CoroutineContext
        get() = parentJob + Dispatchers.Default

    private val scope = CoroutineScope(coroutineContext)
    private val repository : HotpotRepository= HotpotRepository(HotpotAPI.api)

    var authToken: String? = "no token"
    var userId: Long? = null

//    binding stuff
    var btnSelected: ObservableBoolean? = ObservableBoolean(false)
    var email: ObservableField<String>? =  ObservableField("")
    var password: ObservableField<String>? =  ObservableField("")
//    end of binding stuff

    //functions checking to disable button
    fun onEmailChanged(s: CharSequence, start: Int, befor: Int, count: Int) {
        btnSelected?.set(Util.isEmailValid(s.toString()) && password?.get()!!.length >= 8)
    }

我最初在viewModel中将错误消息变量设置为

var errorMessage: ObservableField<String>? =  ObservableField("")

并在xml中像这样使用它

android:error="@{viewmodel.errorMessage}"

并在onEmailChanged中对其进行了更新：

errorMessage.set("Too short input")

即使输入一个字母，该错误也可以显示，并且更新并显示“输入太短”，但是在该字段自动清除错误之后，该错误会完全消失。有没有一种方法可以解决它，使其在清除后更新，还是需要以其他方式进行？预先谢谢你！

使用ViewModel（Kotlin）在editText中添加错误

0 个答案: