添加MediaRouteButton后,我的应用程序崩溃了

Question

我有一些奇怪的问题:

我在我的布局中添加了MediaRouteButton

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/group_right"
    android:layout_width="wrap_content"
    android:layout_height="match_parent"
    android:layout_alignParentRight="true"
    android:orientation="horizontal" >

    <LinearLayout
        android:id="@+id/right_btns"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:minWidth="@dimen/actionbar_icon_width"
        android:orientation="horizontal" >
    </LinearLayout>

    <android.support.v7.app.MediaRouteButton
        android:id="@+id/media_route_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"/>
</LinearLayout>

它在我的新设备上工作得非常好.但对于3.1,3.3或更低版本的旧设备,我遇到了这个例外

Caused by: android.view.InflateException: Binary XML file line #74: Error inflating class android.support.v7.app.MediaRouteButton
at android.view.LayoutInflater.createView(LayoutInflater.java:596)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:671)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:724)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:727)
at android.view.LayoutInflater.inflate(LayoutInflater.java:479) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:391)
at android.view.LayoutInflater.inflate(LayoutInflater.java:347)
at de.myapp.views.MyActionBar.<init>(MyActionBar.java:54)
... 36 more
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Constructor.constructNative(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:416)
at android.view.LayoutInflater.createView(LayoutInflater.java:576)
... 43 more
Caused by: android.content.res.Resources$NotFoundException: Resource is not a Drawable (color or path): TypedValue{t=0x2/d=0x7f01000c a=3}
at android.content.res.Resources.loadDrawable(Resources.java:1841)
at android.content.res.TypedArray.getDrawable(TypedArray.java:601)
at android.view.View.<init>(View.java:2462)
at android.support.v7.app.MediaRouteButton.<init>(MediaRouteButton.java:121)
at android.support.v7.app.MediaRouteButton.<init>(MediaRouteButton.java:117)    
... 46 more

在我的代码中,它发生在我膨胀xml布局时

public MyActionBar(Context context, AttributeSet attrs) {
      super(context, attrs);
      inflate(context, R.layout.group_action_bar, this);
      titleGroup = (ViewGroup) findViewById(R.id.group_title);
      leftBtnGroup = (ViewGroup) findViewById(R.id.left_btns);
      rightBtnGroup = (ViewGroup) findViewById(R.id.right_btns);
      titleAppendix = findViewById(R.id.group_title_appendix);
   }

有谁知道为什么这对api级别较低的旧设备不起作用？

谢谢!!!

Answer 1

我自己可以解决它

问题是drawable/list_selector_background.xml

在Pre-ICS设备上,选择器具有不同的实现.我无法访问support-v7-lib的代码.但设置MediaRouteButton透明背景对我来说很有用.

 <android.support.v7.app.MediaRouteButton
    android:id="@+id/media_route_button"
    android:layout_width="wrap_content"
    android:background="@android:color/transparent"
    android:layout_height="wrap_content"/>