AAPT: ошибка: ошибка несвязанного префикса при использовании androidx.constraintlayout.widget.ConstraintLayout

Question

Я пытаюсь использовать привязку данных, поэтому у меня есть макет root и дочерний объект ограничения, однако при попытке компиляции я получаю AAPT: ошибка: ошибка несвязанного префикса, даже если пространства имен определены.

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:bind="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools"
    tools:context=".View.levels.LevelsActivity">
    <data >
        <variable name="game" type="com.example.gameapp.Model.Game"/>
    </data>

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

    <Button
        bind:id="@+id/Levels_9"
        bind:layout_width="79dp"
        bind:layout_height="79dp"
        bind:layout_marginStart="283dp"
        bind:layout_marginTop="335dp"
        bind:text="9"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
       />

    <Button
        bind:id="@+id/Levels_3"
        bind:layout_width="79dp"
        bind:layout_height="79dp"
        bind:layout_marginStart="283dp"
        bind:layout_marginTop="76dp"
        bind:text="3"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
 />



    <TextView
        bind:id="@+id/LevelStatus"
        bind:layout_width="72dp"
        bind:layout_height="60dp"
        bind:text="@{game.levelUpTo}"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.866"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.87" />

</androidx.constraintlayout.widget.ConstraintLayout>
</layout>

Любой совет?

Answer 1

добавить Android пространство имен

Необходимо добавить атрибут xmlns: android = "http://schemas.android.com/apk/res/android" .. `

<?xml version="1.0" encoding="utf-8"?>
     <layout xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:android="http://schemas.android.com/apk/res/android" 
     xmlns:tools="http://schemas.android.com/tools"
     tools:context=".View.levels.LevelsActivity">
     <data >
            <variable name="game" type="com.example.gameapp.Model.Game"/>
       </data>

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

     <Button
            android:id="@+id/Levels_9"
            android:layout_width="79dp"
            android:layout_height="79dp"
            android:layout_marginStart="283dp"
            android:layout_marginTop="335dp"
            android:text="9"
            android:layout_constraintStart_toStartOf="parent"
            android:layout_constraintTop_toTopOf="parent"
           />

        <Button
            android:id="@+id/Levels_3"
            android:layout_width="79dp"
            android:layout_height="79dp"
            android:layout_marginStart="283dp"
            android:layout_marginTop="76dp"
            android:text="3"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent"
          />



        <TextView
            android:id="@+id/LevelStatus"
            android:layout_width="72dp"
            android:layout_height="60dp"
            android:text="@{game.levelUpTo}"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintHorizontal_bias="0.866"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent"
            app:layout_constraintVertical_bias="0.87" />

    </androidx.constraintlayout.widget.ConstraintLayout>
    </layout>

`