android 返回键

1、重写返回键方法

@Override

public void onBackPressed() {
  

}

2、随时随地退出程序

public class ActivityCollector {
public static List<Activity> activities = new ArrayList<Activity>();

public static void addActivity(Activity activity) {
activities.add(activity);
}

public static void removeActivity(Activity activity) {
activities.remove(activity);
}

public static void finishAll() {
for (Activity activity : activities) {
if (!activity.isFinishing()) {
activity.finish();
}
}
}
}

3、ProgressDialog

如果在setCancelable()中传入了false，表示ProgressDialog 是不能通过Back 键取消
掉