android - 自定义视图在使用时产生数据绑定错误
问题描述
我创建了一个自定义视图，如下所示
class SquareCheckBox @JvmOverloads constructor(
context: Context,
attrs: AttributeSet? = null,
defStyle: Int = 0) : ConstraintLayout (context, attrs, defStyle){
private var layout: ConstraintLayout
private var checkImageView : ImageView
private var iconImageView : ImageView
private var titleTextView : TextView
var isChecked : Boolean = false
var iconImage : Int = -1
var title : String = ""
init {
val inflater = context.getSystemService(Context.LAYOUT_INFLATER_SERVICE) as LayoutInflater
val view = inflater.inflate(R.layout.item_square_checkbox, this, true)
layout = view.layout
checkImageView = view.checkImageView
iconImageView = view.iconImageView
titleTextView = view.titleTextView
initAttributes(attrs)
applyUIChanges()
addAction()
}
fun initAttributes(attrs: AttributeSet?){
attrs?.let {
val typedArray = context.obtainStyledAttributes(it, R.styleable.square_checkbox_attributes, 0, 0)
isChecked = typedArray.getBoolean(R.styleable.square_checkbox_attributes_isChecked, false)
iconImage = typedArray.getResourceId(R.styleable.square_checkbox_attributes_iconImage, -1)
title = typedArray.getString(R.styleable.square_checkbox_attributes_title)
typedArray.recycle()
}
}
fun applyUIChanges () {
if (isChecked) {
checkImageView.visibility = View.VISIBLE
titleTextView.setTextColor(resources.getColor(android.R.color.black))
layout.setBackgroundResource(R.drawable.xml_square_checkbox_selected)
} else {
checkImageView.visibility = View.INVISIBLE
titleTextView.setTextColor(resources.getColor(R.color.lightGray))
layout.setBackgroundResource(R.drawable.xml_square_checkbox_unselected)
}
if (iconImage != -1) {
iconImageView.setImageResource(iconImage)
}
titleTextView.setText(title)
}
fun addAction () {
layout.setOnClickListener(object : View.OnClickListener {
override fun onClick(v: View?) {
isChecked = !isChecked
applyUIChanges()
}
})
}
}
这是xml
<merge xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<androidx.constraintlayout.widget.ConstraintLayout
android:id="@+id/layout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/xml_square_checkbox_unselected">
<ImageView
android:id="@+id/checkImageView"
android:layout_width="20dp"
android:layout_height="20dp"
android:src="@drawable/ic_ckeck"
android:tint="@color/colorPrimary"
android:visibility="visible"
app:layout_constraintEnd_toEndOf="parent"
android:layout_marginTop="4dp"
app:layout_constraintTop_toTopOf="parent"
android:layout_marginEnd="4dp"
android:layout_marginRight="4dp"/>
<ImageView
android:id="@+id/iconImageView"
android:layout_width="35dp"
android:layout_height="35dp"
android:layout_centerHorizontal="true"
android:src="@drawable/ic_placeholder_squre" app:layout_constraintTop_toBottomOf="@+id/checkImageView"
app:layout_constraintBottom_toTopOf="@+id/titleTextView"
app:layout_constraintEnd_toEndOf="parent" android:layout_marginEnd="8dp"
android:layout_marginRight="8dp" app:layout_constraintStart_toStartOf="parent"
android:layout_marginLeft="8dp" android:layout_marginStart="8dp"/>
<TextView
android:id="@+id/titleTextView"
android:layout_width="90dp"
android:layout_height="wrap_content"
android:layout_below="@id/iconImageView"
android:ellipsize="end"
android:gravity="center"
android:lines="2"
android:text="@string/text"
android:maxLines="2"
android:textColor="@android:color/black"
android:textSize="12sp"
android:layout_marginBottom="4dp"
android:layout_marginStart="4dp"
android:layout_marginEnd="4dp"
android:layout_marginRight="4dp"
android:layout_marginTop="8dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/iconImageView"
app:layout_constraintEnd_toEndOf="parent"
/>
</androidx.constraintlayout.widget.ConstraintLayout>
</merge>
现在当我尝试像这样在我的 MVVM 中使用我的自定义视图时
<com.playground.components.SquareCheckBox
android:id="@+id/inAppMessageCheckBox"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:isChecked="@{viewModel.inAppEnabled}"
app:iconImage="@drawable/ic_allow_inapp"
app:title="@string/post_listing_settings_in_app_message"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toStartOf="@+id/voipCheckBox" android:layout_marginStart="8dp"
android:layout_marginEnd="8dp">
它给了我以下错误
****/ data binding error ****msg:Cannot find the setter for attribute 'app:isChecked' with parameter type boolean on com.playground.components.SquareCheckBox. file:/Volumes/Data/Work/Amira_Playground/Playground/app/src/main/res/layout/recycler_view_basic_information_settings_item.xml loc:20:33 - 20:54 ****\ data binding error ****
有人可以请教吗？
解决方案
似乎它应该可以工作，但也许 setter 的名称/参数解析存在问题。文档指出：
对于名为 example 的属性，库会自动尝试查找接受兼容类型作为参数的方法 setExample(arg)。不考虑属性的命名空间，仅在搜索方法时使用属性名称和类型。
您可以使用自定义绑定适配器轻松解决此问题。请参阅：https ://developer.android.com/topic/libraries/data-binding/binding-adapters
像这样：
@BindingAdapter("isChecked")
fun setIsChecked(view: SquareCheckBox, checked: Boolean) {
view.setChecked(checked)
}