Android：找不到符号类DataBinderMapperImpl找不到适用于Android的吸气剂：state_checked

问题描述

我正在尝试将双向数据绑定与dagger hilt和viewmodel结合使用。但是，我的问题是我的构建失败，并显示错误...

错误代码

Task :app:kaptDebugKotlin
C:\Users\Censored\AndroidStudioProjects\Example\app\build\generated\source\kapt\debug\com\example\app\DataBinderMapperImpl.java:9: error: cannot find symbol
import com.example.app.databinding.CalibrateRepairMessageContentBindingImpl;
                                  ^
  symbol:   class CalibrateRepairMessageContentBindingImpl

Task :app:kaptDebugKotlin FAILED
  location: package com.example.app.databinding

Android似乎无法创建我的数据绑定xml的impl文件。

这是我的代码：

XML文件，包含在我的fragment_calibrate_repair_message中

<?xml version="1.0" encoding="utf-8"?>
<layout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools">

    <data>
        <variable
            name="viewModel"
            type="com.example.app.data.viewmodel.EmailViewModel" />
    </data>

<androidx.constraintlayout.widget.ConstraintLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.google.android.material.textfield.TextInputLayout
        android:id="@+id/calibrate_repair_message_input">

        <com.google.android.material.textfield.TextInputEditText
            <!-- DATA BINDING -->
            android:text="@={viewModel.etMessage}"/>

    </com.google.android.material.textfield.TextInputLayout>

    <com.google.android.material.card.MaterialCardView
        android:id="@+id/calibrate_repair_ex_option_ONE"
        android:checkable="true"
        android:clickable="true"
        android:focusable="true"
        <!-- DATA BINDING -->
        android:state_checked="@={viewModel.cardOptionOneChecked}">

    </com.google.android.material.card.MaterialCardView>

    <com.google.android.material.card.MaterialCardView
        android:id="@+id/calibrate_repair_ex_option_TWO"
        android:checkable="true"
        android:clickable="true"
        android:focusable="true"
        <!-- DATA BINDING -->
        android:state_checked="@={viewModel.cardOptionTwoChecked}">

    </com.google.android.material.card.MaterialCardView>
</androidx.constraintlayout.widget.ConstraintLayout>
</layout>

BaseFragment，在这里初始化了dataBinding

abstract class BaseFragment<B: ViewDataBinding>(val layout: Int) : Fragment() {
    //... Some variables that have nothing to do with dataBinding

    // Here I am using Databinding! Using BaseFragment because all my fragments use dataBinding
    override fun onCreateView(inflater: LayoutInflater,container: ViewGroup?,savedInstanceState: Bundle?): View? {
        val binding = DataBindingUtil.inflate<B>(inflater,layout,container,false)
        return binding.root
    }
}

电子邮件片段

abstract class EmailFragment<B: ViewDataBinding>(
    layout: Int,//... etc
) : BaseFragment<B>(layout) {
    //... Some variables that have nothing to do with dataBinding

    override fun onViewCreated(view: View,savedInstanceState: Bundle?) {
        super.onViewCreated(view,savedInstanceState)
        //... Some functions that have nothing to do with dataBinding
    }

CalibrateRepairMessageFragment，问题出在这里！

class CalibrateRepairMessageFragment(//...): 
// Here I am providing the actual DataBiding class "CalibrateRepairMessageContentBinding"
EmailFragment<CalibrateRepairMessageContentBinding>(
        R.layout.fragment_calibrate_repair_message,//..
    ) {

ViewModel

class EmailViewModel @ViewModelInject constructor(
    @Assisted private val savedStateHandle: SavedStateHandle
) : ViewModel() {

    // My three properties which are declared in my layout.xml
    val etMessage = MutableLiveData<String>()

    val cardOptionOneChecked = MutableLiveData<Boolean>()
    
    val cardOptionTwoChecked = MutableLiveData<Boolean>()
}

我希望代码不要过多或混乱。我试图删除对我的问题不重要的所有内容（例如布局内容或不必要的功能）。在我的build.gradle中启用了数据绑定。

我知道，已经问过这个问题，但是没有人使用匕首-希尔特，我想这是我的问题吗？我感谢所有帮助，谢谢！

编辑

我更改了BaseFragment类和CalibrateMessageFragment类以附加我的视图模型。不幸的是，这并没有解决我的问题...

• 新BaseFragment

   abstract class BaseFragment<T: ViewDataBinding>(val layout: Int) : Fragment() {
   abstract val viewModel: ViewModel // new
  
   // New
   override fun onCreateView(inflater: LayoutInflater,savedInstanceState: Bundle?): View? {
       return DataBindingUtil.inflate<T>(inflater,false).apply {
           lifecycleOwner = viewLifecycleOwner
           setVariable(BR.viewModel,viewModel)
       }.root
   }
  }
  

• CalibrateMessageFragment

   class CalibrateRepairMessageFragment(//...): 
       EmailFragment<CalibrateRepairMessageBinding>(
               R.layout.fragment_calibrate_repair_message,//..
           ) {
         // New
        override val viewModel: EmailViewModel by viewModels()
   }
  

编辑2

好吧，我又走了一步，发现com.google.android.material.card.MaterialCardView不能为android:state_checked提供吸气剂吗？我的错误至少显示以下内容：

[databinding] {"msg":"Cannot find a getter for \u003ccom.google.android.material.card.MaterialCardView android:state_checked\u003e that accepts parameter type \u0027java.lang.Boolean\u0027\n\n
If a binding adapter provides the getter,check that the adapter is annotated correctly and that the parameter type matches.","file":"app\\src\\main\\res\\layout\\calibrate_message_content.xml","pos":[{"line0":63,"col0":8,"line1":135,"col1":59}]}

但这没有任何意义，因为here您可以看到CardView为isChecked提供了一个吸气剂。

解决方法

好的，我已经通过编写自己的BindingAdapter.kt解决了问题，这是代码：

@BindingAdapter("state_checked")
fun setStateChecked(view: MaterialCardView,liveData: MutableLiveData<Boolean>) {
    if (view.isChecked != liveData.value) {
        liveData.value = view.isChecked
    }
}

@InverseBindingAdapter(attribute = "state_checked")
fun getStateChecked(view: MaterialCardView,): Boolean {
    return view.isChecked
}

@BindingAdapter("state_checkedAttrChanged")
fun setCheckedAttrListener(
    view: MaterialCardView,attrChange: InverseBindingListener,) {
   view.setOnClicklistener {
   // logic is here
   }
   attrChange.onChange()
}

唯一的问题是我不知道要实现一种逻辑，以便我的MaterialCardView像Radio组一样工作。伤心。