无法膨胀Behavior子类

Question

我想基于How do I remove the bouncing effect on appbar?定制一个行为

但它总是在运行时崩溃：

2020-08-27 08:25:18.096 E/UncaughtException: java.lang.RuntimeException: Unable to start activity ComponentInfo{tw.com.colatour.dev/tw.com.colatour.ui.mp.home.MpHomeActivity}: android.view.InflateException: Binary XML file line #9: Could not inflate Behavior subclass tw.com.colatour.dev.ui.app_home.ad.one.NoBounceBehavior
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2779)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2844)
        at android.app.ActivityThread.-wrap12(ActivityThread.java)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1572)
        at android.os.Handler.dispatchMessage(Handler.java:110)
        at android.os.Looper.loop(Looper.java:203)
        at android.app.ActivityThread.main(ActivityThread.java:6364)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1063)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:924)
     Caused by: android.view.InflateException: Binary XML file line #9: Could not inflate Behavior subclass tw.com.colatour.dev.ui.app_home.ad.one.NoBounceBehavior
     Caused by: java.lang.RuntimeException: Could not inflate Behavior subclass tw.com.colatour.dev.ui.app_home.ad.one.NoBounceBehavior
        at androidx.coordinatorlayout.widget.CoordinatorLayout.parseBehavior(CoordinatorLayout.java:622)

我如何在XML中使用它：

...
    <com.google.android.material.appbar.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@color/white"
        app:layout_behavior=".ui.app_home.ad.one.NoBounceBehavior"
        android:fitsSystemWindows="true"> 
...

这是Java代码解决方案，但我不知道如何将其转换为Kotlin代码。

public class NoBounceBehavior extends AppBarLayout.Behavior {
    
    public FooterBehavior() {
    }

    public FooterBehavior(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

Kotlin代码：

//crash
class NoBounceBehavior(context: Context, attrs: AttributeSet) :
      AppBarLayout.Behavior(context, attrs) {

...

另一次尝试也失败了：

//crash
class NoBounceBehavior(context: Context, attrs: AttributeSet) :
      AppBarLayout.Behavior(context, attrs) {

    constructor() {}

    constructor(context: Context, attrs: AttributeSet) {}
...

Answer 1

您必须在XML声明中使用自定义行为的完全限定名称。如果XML中指定的名称以".“开头，则为coordinator layout appends the package name at runtime。如果您的应用程序在构建时将任何内容附加到包名称(即".beta“或".dev")，则包名称将与此处的包路径不匹配。改用下面的代码：

<com.google.android.material.appbar.AppBarLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/white"
    app:layout_behavior="tw.com.colatour.ui.app_home.ad.one.NoBounceBehavior"
    android:fitsSystemWindows="true">