android – 在奇怪的延迟后显示活动

只要单击菜单项或可单击视图,onClickListener就会创建一个新的Intent并启动指定的活动.到目前为止还可以.但是,在用户看到新活动之前,视图会被冻结一段时间(大约1秒).

那个时间可能是由onCreate里面的进展引起的,但是我通过System.currentTimeMillis()测量时间并在结尾处将其打印在logcat中.因此,它似乎只需要20-30毫秒,并且在用户看到活动之前很久就会打印日志.

这是我的代码：

public class ExampleActivity extends MyActivity {

    Mymodel mymodel;
    long startTime;


    protected void onCreate(Bundle savedInstanceStatE) {
        super.onCreate(savedInstanceStatE);
        startTime = System.currentTimeMillis();
        setContentView(R.layout.activity_ders_programi);
        setToolbar();

        mymodel = Controller.getMymodel();
        if(mymodel == null) { //If we don't have the object prevIoUsly
            //this fills the object,takes some time
            mymodel = new Mymodel(this);
            //mymodel is observable and this activity is observer.
            //Whenever it's done,it notifies this activity
        }
        else //If we got the object prevIoUsly
            createCardViews();
        Controller.setMymodel(mymodel);

        setParentActivity();
    }


    //If Observable object notifies this activity,update() is called.
    @Override
    public void update(Observable observable,Object o) {
        createCardViews();
    }


   //CreaTing a list of cardViews,this also takes some time
   private void createCardViews() {
       ArrayList<Card> cards = new ArrayList<Card>();
       for(int i = 0; i < 5; i++) {
           MymodelCardModel card = new MymodelCardModel(this,i);
           card.init();
           cards.add(card);
       }

       CardArrayAdapter mCardArrayAdapter = new CardArrayAdapter(this,cards);

       CardListView listView = (CardListView) findViewById(R.id.my_card_list_view);
       if (listView!=null)
           listView.setAdapter(mCardArrayAdapter);

       //I think here is the last point.
       //After this point there will be no significant process.
       long stopTime = System.currentTimeMillis();
       Log.d("modelflow","card create takes: " + (stopTime - startTimE) + "ms");

}

那么我做错了什么？如果延迟是因为进度很大,那么为什么测得的时间似乎很少.假设进度导致延迟,为什么应用程序在显示活动后没有等待？以及如何避免这种情况？