Kotlin OnClickListener 未在 ConstraintLayout 上触发

在我的android应用程序项目中，我必须在后台制作一个带有进度条和两个文本视图的按钮.

I make a first attempt like this:

    <android.support.constraint.ConstraintLayout
        android:id="@+id/keyboard_touch_1"
        android:layout_width="60dp"
        android:layout_height="85dp"
        android:layout_marginBottom="150dp"
        android:layout_marginStart="10dp"
        android:focusable="true"
        android:clickable="true"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent">

        <ProgressBar
            android:id="@+id/keyboard_touch_1_progress_bar"
            style="@android:style/Widget.ProgressBar.Horizontal"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:indeterminate="false"
            android:max="100"
            android:progress="50"
            android:progressDrawable="@drawable/button_progress_bar_default"
            android:clickable="false"
            android:focusable="false" />

        <TextView
            android:id="@+id/keyboard_touch_1_score"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentStart="true"
            android:layout_marginEnd="8dp"
            android:layout_marginTop="8dp"
            android:text="2"
            android:textColor="@color/colorAccent"
            android:textSize="11dp"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintTop_toTopOf="parent"
            tools:text="3"
            android:clickable="false"
            android:focusable="false" />

        <TextView
            android:id="@+id/keyboard_touch_1_letter"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentStart="true"
            android:layout_marginTop="13dp"
            android:text="A"
            android:textColor="@color/colorAccent"
            android:textSize="45dp"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent"
            android:clickable="false"
            android:focusable="false" />

    </android.support.constraint.ConstraintLayout>

It looks good but when i attempt to add an OnClickListener it doesn't work correctly.

keyboard_touch_1.setOnClickListener {
    Toast.makeText(this, "IT WORKS !!!", Toast.LENGTH_SHORT).show()
}

The OnClickListener is not fired and i have no idea of why. It's probably very simple but i doesn't understand why.

Thanks in advance.