3

是否可以在菜单资源中使用View Binding（或）？Data Binding

override fun onCreateOptionsMenu(menu: Menu): Boolean {
    menuInflater.inflate(R.menu.menu_main, menu)
    
    // search using ID - can this be replaced by view binding?
    val searchView = menu.findItem(R.id.menu_search).actionView as SearchView
}
4

3 回答 3

3

在大多数情况下，视图绑定替换了findViewById.

根据文件：

视图绑定是一项功能，可让您更轻松地编写与视图交互的代码。一旦在模块中启用视图绑定，它就会为该模块中存在的每个XML 布局文件生成一个绑定类。

它在菜单中使用findItem()而不是findViewById()方法。

于 2020-07-22T18:45:25.817 回答
1

特定于带有自定义 xml 视图的菜单项的视图绑定，而不是 数据绑定：

partial_menu_sample_view.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="?actionBarSize"
    android:layout_height="?actionBarSize"
    android:clipToPadding="false"
    android:focusable="true">

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:contentDescription="@null"
        android:src="@drawable/ic_sample"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />


    <TextView
        android:id="@+id/textview_sample"
        android:visibility="gone"
        app:layout_constraintBottom_toTopOf="@id/guideline_horizontal_center"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="@id/guideline_vertical_center"
        app:layout_constraintTop_toTopOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

activity_sample.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

  <androidx.appcompat.widget.Toolbar 
    android:id="@+id/toolbar_sample"/>

</LinearLayout>

SampleActivity.kt

class SampleActivity() {

  lateinit var binding: ActivitySampleBinding
  var menuSampleViewBinding: PartialMenuSampleViewBinding? = null

  ...

  override fun onCreate() {
    super.onCreate()
    binding = ActivitySampleBinding.inflate(layoutInflater)
    setContentView(binding.root)
    // make sure to set the toolbar
    setSupportActionBar(binding.toolbarSample)
  }

  ...

  override fun onCreateOptionsMenu() {
      // inflate the menu to show on your toolbar
      // replace with your own menu xml
      binding.toolbarProduct.inflateMenu(R.menu.activity_sample)
      
      with(binding.toolbarProduct.menu) {
            findItem(R.id.menu_item_cart)?.actionView?.let {
                menuSampleViewBinding = PartialMenuSampleViewBinding.bind(it)
            }
            // handle other menu items here
      }
  }

  ...

  fun customFunction() {
      // use as needed
      menuSampleViewBinding?.textviewSample?.text = "1"
      menuSampleViewBinding?.root?.setOnClickListeners { /* add what you need */ } 
  }

}

在菜单项上有徽章计数的用例中使用它。工作正常。

于 2021-03-05T10:59:18.370 回答
0

目前，dataBinding只针对布局资源，不针对菜单资源。

于 2020-07-22T18:51:29.907 回答