在使用操作提供程序创建菜单时，我收到一个 ClassCastException 错误，指出该类无法转换为 View。我在 DevGuide 中使用了关于 ActionProviders 的小教程所以我不确定哪里出了问题。

public class CustomActionView extends ActionProvider{

private final Context mContext;


public CustomActionView(Context context) {
    super(context);
    mContext = context;
}

@Override
public View onCreateActionView() {
    LayoutInflater inflater = LayoutInflater.from(mContext);
    View view = inflater.inflate(R.layout.action_layout,null);
    ImageButton button = (ImageButton)view.findViewById(R.id.imageButton1);

    button.setOnClickListener(new View.OnClickListener(){

        @Override
        public void onClick(View v) {
            Intent i = new Intent(mContext,com.app.notifyme.SmsPrefs.class);
            mContext.startActivity(i);
        }

    });
    return view;
} 

@Override
public boolean onPerformDefaultAction() {
    Intent i = new Intent(mContext,com.app.notifyme.SmsPrefs.class);
    mContext.startActivity(i);
    return true;
}
}

菜单xml

<menu xmlns:android="http://schemas.android.com/apk/res/android" >

<item android:id="@+id/prefs"
    android:title="Home"
    android:icon="@drawable/android"
    android:actionViewClass="com.app.notifyme.ICS.CustomActionView"/>

<item android:id="@+id/add"
    android:title="SMS/MMS"
    android:icon="@drawable/android"
    android:actionViewClass="com.app.notifyme.ICS.ContactActionView"/>

</menu>

日志错误:

12-21 18:28:58.358: E/AndroidRuntime(17607): java.lang.ClassCastException: com.app.notifyme.ICS.CustomActionView cannot be cast to android.view.View
12-21 18:28:58.358: E/AndroidRuntime(17607):    at android.view.MenuInflater$MenuState.setItem(MenuInflater.java:415)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at android.view.MenuInflater$MenuState.addItem(MenuInflater.java:436)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at android.view.MenuInflater.parseMenu(MenuInflater.java:173)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at android.view.MenuInflater.inflate(MenuInflater.java:95)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at com.app.notifyme.SmsMain.onCreateOptionsMenu(SmsMain.java:68)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at android.app.Activity.onCreatePanelMenu(Activity.java:2444)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at com.android.internal.policy.impl.PhoneWindow.preparePanel(PhoneWindow.java:388)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at com.android.internal.policy.impl.PhoneWindow.invalidatePanelMenu(PhoneWindow.java:739)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at com.android.internal.policy.impl.PhoneWindow$1.run(PhoneWindow.java:2811)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at android.os.Handler.handleCallback(Handler.java:605)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at android.os.Handler.dispatchMessage(Handler.java:92)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at android.os.Looper.loop(Looper.java:137)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at android.app.ActivityThread.main(ActivityThread.java:4340)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at java.lang.reflect.Method.invokeNative(Native Method)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at java.lang.reflect.Method.invoke(Method.java:511)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
12-21 18:28:58.358: E/AndroidRuntime(17607):    at dalvik.system.NativeStart.main(Native Method)

最佳答案

导入没有粘贴在代码中，但是如果你使用 ActionBarSherlock (ABS) 作为 ActionBar，你必须导入 com.actionbarsherlock.view.ActionProvider 而不是标准的 import android.view.ActionProvider;

关于android - 带有自定义 ActionProvider 的 ClassCastException，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/8598070/