Question

我正在尝试从中删除项目后刷新列表视图，但我没有找到所需的结果。当我重新加载活动时，项目将被删除，但在我按下删除按钮时不会删除。这是我的代码：

public void deletelist()
{
    mylist = new ArrayList<HashMap<String,Object>>();
    HashMap<String,Object> map = new HashMap<String, Object>();

    for(int i=0;i<favtitle.size();i++)
    {
        map = new HashMap<String, Object>();
        map.put("train",favtitle.get(i));
        map.put("value",favloc.get(i));
        map.put("employer",favemp.get(i));

        mylist.add(map);
    }

    mSchedule = new SimpleAdapter(this, mylist, R.layout.listdelete,
            new String[] {"train","value","employer"}, new int[] {R.id.dept,R.id.jobloc,R.id.employer});
    lv.setAdapter(mSchedule);
    lv.setDividerHeight(2);
    lv.setCacheColorHint(Color.WHITE);

    lv.setOnItemClickListener(new OnItemClickListener() {
        public void onItemClick(AdapterView<?> parent,View view,int position,long id)
        {

            String str3 = favtitle.get(position);
            db.delete("Favorites7","title= '"+str3+"'",null);

            db.close();
            //Data Base Select
            db = openOrCreateDatabase(
                    "ClassifiedAds.db"
                    , SQLiteDatabase.CREATE_IF_NECESSARY
                    , null
            );

            db.setVersion(1);
            db.setLocale(Locale.getDefault());
            db.setLockingEnabled(true);

            //End-----
            cur= db.query("Favorites7", 
                    null, null, null, null, null, null);

            cur.moveToFirst();
            while (cur.isAfterLast() == false) {

                favtitle.add(cur.getString(1));
                favloc.add(cur.getString(3));
                favemp.add(cur.getString(2));
                lat.add(cur.getString(7));
                log.add(cur.getString(8));

                cur.moveToNext();
            }

            cur.close();

            //mylist = new ArrayList<HashMap<String,Object>>();
            HashMap<String,Object> map = new HashMap<String, Object>();

            for(int i=0;i<favtitle.size();i++)
            {
                map = new HashMap<String, Object>();
                map.put("train",favtitle.get(i));
                System.out.println("==="+favtitle.get(i));
                map.put("value",favloc.get(i));
                System.out.println("==="+favloc.get(i));
                map.put("employer",favemp.get(i));
                System.out.println("==="+favemp.get(i));

                mylist.add(map);
            }

            mSchedule.notifyDataSetChanged(); 
            mSchedule = new SimpleAdapter(Favorites.this, mylist, R.layout.listdelete,
                    new String[] {"train","value","employer"}, new int[] {R.id.dept,R.id.jobloc,R.id.employer});
            lv.setAdapter(mSchedule);
            lv.setDividerHeight(2);
            lv.setCacheColorHint(Color.WHITE);


        }
    });
}

任何帮助将不胜感激。提前完成。

Answer 1

使用 notifyDataSetChanged（）方法在您要删除记录的情况下使用listview，只需在删除记录后添加 listview.notifyDataSetChanged（）代码。希望这能解决你的问题。

Answer 2

您是否尝试过invalidateViews，它会重新绘制列表视图。

Answer 3

我的问题解决了。我必须做的是，每当arraylist重新加载我必须清除前一个。像：

数组列表名称 .clear（）; 在将项添加到hashmap之前。

列表没有刷新

3 个答案: