android - ListView 和带倒数计时器的项目

Question

我的 Listview 有问题，我想为所有 ListView 的项目设置一个倒数计时器，我已经在 google 上搜索了解决方案，但它无法正常工作。问题是 ListView 重用(回收) View ，我总是得到错误的项目时间。我为我的 View 使用了标签，但它仍然不起作用，我不明白我在哪里犯了错误，请帮助我。谢谢。

所以这里的图片显示了我的问题:pic1 我刚开始 Activity 的地方；

pic2 我刚刚向下和向上滚动的地方

这是我的代码(全类):

已更新

    public class PromoListActivity extends SherlockActivity {
private ListView mPromoList;
private PromoListAdapter mAdapter;
private ViewFlipper mFlipper;
private Button mBtnRepeat;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.fragment_news_list);
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    setTitle("Сохранённые акции");
    mFlipper = (ViewFlipper) findViewById(R.id.flipper);
    mPromoList = (ListView) findViewById(R.id.newsList);
    mBtnRepeat = (Button) findViewById(R.id.btnRepeat);
    
    //-->
    final Handler timerHandler = new Handler();
    Runnable timerRunnable = new Runnable() {
        @Override
        public void run() {
            mAdapter.notifyDataSetChanged();
            timerHandler.postDelayed(this, 1000); // run every minute
        }
    };
    //<--
    
    
    mBtnRepeat.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View arg0) {
            mFlipper.setDisplayedChild(0);
            getDummyData();
        }
    });
    mPromoList.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
            startActivity(new Intent(PromoListActivity.this, PromoActivityDetails.class));

        }
    });
    getDummyData();
}

private class PromoListAdapter extends BaseAdapter {
    private ArrayList<PromoAction> mItems = new ArrayList<PromoAction>();
    private LayoutInflater layoutInflater;

    private PromoListAdapter(Context context, ArrayList<PromoAction> mItems) {
        layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        this.mItems = mItems;
    }

    public int getCount() {
        return mItems.size();
    }

    public PromoAction getItem(int position) {
        return mItems.get(position);
    }

    public long getItemId(int position) {
        return position;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        ViewItem viewItem;
        PromoAction promoAction = getItem(position);
        if (convertView == null) {
            viewItem = new ViewItem();
            convertView = layoutInflater.inflate(R.layout.listviewitem_action, null);
            viewItem.name = (TextView) convertView.findViewById(R.id.promoAction_name);
            viewItem.desc = (TextView) convertView.findViewById(R.id.promoAction_desc);
            viewItem.timer = (TextView) convertView.findViewById(R.id.promoAction_timer);
            viewItem.timer.setTag(position);
            convertView.setTag(viewItem);
        } else {
            viewItem = (ViewItem) convertView.getTag();
        }
        setTime(promoAction,viewItem.timer,viewItem.timer.getTag().toString());
        viewItem.name.setText(promoAction.name);
        viewItem.desc.setText(promoAction.descr);
        return convertView;
    }

    private void setTime(final PromoAction promoAction, final TextView tv, final String tag) {
        if (tv.getTag().toString().equals(tag)) {
            long outputTime = Math.abs(promoAction.timer_end
                    - System.currentTimeMillis());
            Date date = new java.util.Date(outputTime);
            String result = new SimpleDateFormat("hh:mm:ss").format(date);
            tv.setText(result);
        }
    }

    public class ViewItem {
        TextView name;
        TextView desc;
        TextView timer;
    }
}

private void getDummyData() {
    ArrayList<PromoAction> list = new ArrayList<PromoAction>();
    for (int i = 1; i < 10; i++) {
        PromoAction action = new PromoAction();
        action.name = "Lorem ipsum dolor sit amet";
        action.descr = "Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. ";
        switch (i) {
        case 1: {
            action.timer_start = 1385971000;
            action.timer_end = 1386104000;
        }
        case 2: {
            action.timer_start = 1385889000;
            action.timer_end = 1385812550;
            break;
        }
        case 3: {
            action.timer_start = 1385884200;
            action.timer_end = 1385912100;
            break;
        }
        default: {
            action.timer_start = 1385856000;
            action.timer_end = 1385892000;
            break;
        }
        }
        list.add(action);

    }
    mAdapter = new PromoListAdapter(PromoListActivity.this, list);
    mPromoList.setAdapter(mAdapter);
    mFlipper.setDisplayedChild(1);
}

Answer 1

在我的案例中，我以不同的方式解决了这个问题。我没有在 getView() 中设置计时器处理程序，而是每次 getView 时都将当前时间和所需时间之间的时差设置到 TextView () 被调用。因此，将您的这段代码移回 getView() 中:

long outputTime = Math.abs(promoAction.timer_end
                    - System.currentTimeMillis());
Date date = new java.util.Date(outputTime);
String result = new SimpleDateFormat("hh:mm:ss").format(date);
tv.setText(result);

然后在 Activity 中创建一个处理程序，每隔一分钟在 ListView 的适配器上调用 notifyDatasetChanged():

Handler timerHandler = new Handler();
Runnable timerRunnable = new Runnable() {
    @Override
    public void run() {
        myAdapter.notifyDataSetChanged();
        timerHandler.postDelayed(this, 60000); //run every minute
    }
};

我在 onPause() 上停止了这个处理程序:

@Override
protected void onPause() {
    timerHandler.removeCallbacks(timerRunnable);
    super.onPause();
}

然后我在 onResume() 上再次启动它:

@Override
protected void onResume() {
    timerHandler.postDelayed(timerRunnable, 500);
    super.onResume();
}

就是这样。 :)

希望对您有所帮助。