滚动监听器上的 PreferenceFragmentCompat

Question

我正在使用 PreferenceFragmentCompat 创建一个设置屏幕，我想在用户上下滚动时执行一些功能，因此我需要检测用户滚动，我如何才能听到偏好屏幕滚动？下面是我的布局代码

<PreferenceScreen xmlns:app="http://schemas.android.com/apk/res-auto">

<PreferenceCategory
    app:allowDividerAbove="false"
    app:allowDividerBelow="false"
    app:iconSpaceReserved="false"
    app:title="General">

    <SwitchPreference
        app:iconSpaceReserved="false"
        app:key="@string/theme_dark_key"
        app:title="@string/theme_dark" />

</PreferenceCategory>

<PreferenceCategory
    app:allowDividerAbove="false"
    app:allowDividerBelow="false"
    app:iconSpaceReserved="false"
    app:title="Account">

    <Preference
        app:iconSpaceReserved="false"
        app:key="@string/changeEmailKey"
        app:title="@string/changeEmailTitle" />

    <Preference
        app:iconSpaceReserved="false"
        app:key="@string/changePassKey"
        app:title="@string/changePassTitle" />

    <Preference
        app:iconSpaceReserved="false"
        app:key="@string/sign_out_key"
        app:title="@string/sign_out" />

</PreferenceCategory>

<PreferenceCategory
    app:allowDividerAbove="false"
    app:allowDividerBelow="false"
    app:iconSpaceReserved="false"
    app:title="Social">

    <Preference
        app:iconSpaceReserved="false"
        app:key="@string/blockListKey"
        app:summary="@string/blockListSummery"
        app:title="@string/blockListTitle" />

    <Preference
        app:iconSpaceReserved="false"
        app:key="@string/contactKey"
        app:summary="@string/contactSummery"
        app:title="@string/contactTitle" />


    <SwitchPreference
        app:iconSpaceReserved="false"
        app:key="@string/notificationKey"
        app:title="@string/notificationTitle" />

</PreferenceCategory>

<PreferenceCategory
    app:allowDividerAbove="false"
    app:allowDividerBelow="false"
    app:iconSpaceReserved="false"
    app:title="Others">

    <Preference
        app:iconSpaceReserved="false"
        app:key="@string/reportProblemKey"
        app:summary="@string/reportProblemSummery"
        app:title="@string/reportProblemTitle" />

</PreferenceCategory>

</PreferenceScreen>

这是我的事件布局

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="?attr/backgroundColor"
android:orientation="vertical">

<com.google.android.material.appbar.AppBarLayout
    android:id="@+id/toolbarLayout"
    android:layout_width="match_parent"
    android:layout_height="?attr/actionBarSize"
    android:background="?attr/backgroundColor"
    app:elevation="0dp">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_marginStart="10dp"
        android:layout_marginEnd="10dp"
        android:animateLayoutChanges="true"
        android:orientation="horizontal">

        <ImageView
            android:id="@+id/settingBack"
            android:layout_width="35dp"
            android:layout_height="match_parent"
            android:contentDescription="@string/none"
            android:src="?attr/mic_back" />

        <TextView
            android:id="@+id/settingTitle"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:contentDescription="@string/none"
            android:gravity="center_vertical"
            android:paddingStart="10dp"
            android:paddingEnd="10dp"
            android:textColor="?attr/textColor"
            android:textSize="16sp" />

    </LinearLayout>

</com.google.android.material.appbar.AppBarLayout>

<FrameLayout
    android:id="@+id/setting_container"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

</LinearLayout>

这是我的事件课

class SettingActivity : AppCompatActivity() {

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)

    setContentView(R.layout.activity_setting)

    supportFragmentManager.beginTransaction().replace(R.id.setting_container, settingFragment).commit()

}
}

这是偏好片段

class SettingPreferenceFragment: PreferenceFragmentCompat() {


override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
    setPreferencesFromResource(R.xml.preference, rootKey)
}

Answer 1

在 onCreatePreferences 中，您可以将滚动监听器添加到首选项的“ListView”(在较新的 API 上，它实际上是一个 RecyclerView)。唯一的问题是当 onCreatePreferences 被调用时，getListView() 返回 null。通常我会使用 doOnPreDraw，但没有 View 可以轻松访问。相反，您可以使用 Handler 来延迟调用，直到 Views 布局完毕。

Handler(Looper.getMainLooper()).post {
    listView.setOnScrollChangeListener { view, x, y, dX, dY ->
        // Code here
    }
}