Question

我试图使用一个类扩展为Listfragment但我无法打开它。

我有2个活动，firts是主要的，并扩展ActionBarActivity以获取旧API的操作栏：

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.View;


    public class MainActivity extends  ActionBarActivity {

    //......

    public void makeAndEvent (View v){

    Intent intent = new Intent(getBaseContext(), Events.class);
            startActivity(intent);
        }
    }

这里的秒数是冲突的：

import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.ListFragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;



public class Events extends ListFragment {



    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.activity_events, container, false);
        return rootView;
    }
}

但是，当应用程序尝试启动第二个活动，事件时，我在日志中收到此错误：

08-02 18:59:38.279: E/AndroidRuntime(12284): FATAL EXCEPTION: main
08-02 18:59:38.279: E/AndroidRuntime(12284): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.app.myapp/com.app.myapp.Events}: java.lang.ClassCastException: com.app.myapp.Events cannot be cast to android.app.Activity
08-02 18:59:38.279: E/AndroidRuntime(12284):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1998)
08-02 18:59:38.279: E/AndroidRuntime(12284):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2099)
08-02 18:59:38.279: E/AndroidRuntime(12284):    at android.app.ActivityThread.access$600(ActivityThread.java:138)
08-02 18:59:38.279: E/AndroidRuntime(12284):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1205)
08-02 18:59:38.279: E/AndroidRuntime(12284):    at android.os.Handler.dispatchMessage(Handler.java:99)
08-02 18:59:38.279: E/AndroidRuntime(12284):    at android.os.Looper.loop(Looper.java:137)
08-02 18:59:38.279: E/AndroidRuntime(12284):    at android.app.ActivityThread.main(ActivityThread.java:4929)
08-02 18:59:38.279: E/AndroidRuntime(12284):    at java.lang.reflect.Method.invokeNative(Native Method)
08-02 18:59:38.279: E/AndroidRuntime(12284):    at java.lang.reflect.Method.invoke(Method.java:511)
08-02 18:59:38.279: E/AndroidRuntime(12284):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:798)
08-02 18:59:38.279: E/AndroidRuntime(12284):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:565)
08-02 18:59:38.279: E/AndroidRuntime(12284):    at dalvik.system.NativeStart.main(Native Method)
08-02 18:59:38.279: E/AndroidRuntime(12284): Caused by: java.lang.ClassCastException: com.app.myapp.Events cannot be cast to android.app.Activity
08-02 18:59:38.279: E/AndroidRuntime(12284):    at android.app.Instrumentation.newActivity(Instrumentation.java:1056)
08-02 18:59:38.279: E/AndroidRuntime(12284):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1989)

有人可以帮助我吗？

Answer 1

无法启动碎片。它们将被包含在活动中。您可以使用ListActivity或在FragmentActivity上添加ListFragment。

Listfragment无法强制转换为android.app.activity

1 个答案: