创建扩展应用程序的类并保持实例那里。

Create a class that extends Application and hold the instance there.

class MyApp extends Application{
    private Object obj;
    public Object getObject(){
         return obj;
    }
}

然后在你的活动

MyApp ma = (MyApp)getApplicationContext();
Object o = ma.getObject();

您可以阅读更多关于Android开发者网站上的应用程序类：http://developer.android.com/reference/android/app/Application.html

You can read more about the Application class on the android developer website: http://developer.android.com/reference/android/app/Application.html