定义MySharedPreferencesFor类

 

public class MySharedPreferences{      SharedPreferences sp;      SharedPreferences.Editor editor;      Context context;      public MySharedPreferences(Context context,String fileName){            this.context =context;            sp=context.getSharedPreferences(fileName,Context.MODE_PRIVATE);            editor=sp.edit();      }            public void putValue(String key,String value){             editor.putString(key,value);             editor.commit();       }                public String getValue(String key){              return sp.getString(key,null);        }         //存储list         public void saveInfo(Context context, String key, List<Map<String, Object>> datas) {    JSONArray mJsonArray = new JSONArray();    for (int i = 0; i < datas.size(); i++) {        Map<String, Object> itemMap = datas.get(i);        Iterator<java.util.Map.Entry<String, Object>> iterator = itemMap.entrySet().iterator();         JSONObject object = new JSONObject();         while (iterator.hasNext()) {            java.util.Map.Entry<String, Object> entry = iterator.next();            try {                object.put(entry.getKey(), entry.getValue());            } catch (JSONException e) {                   e.printStackTrace();            }        }        mJsonArray.put(object);    }    editor.putString(key, mJsonArray.toString());    editor.commit();} public List<Map<String, Object>> getInfo(Context context, String key) {    List<Map<String, Object>> datas = new ArrayList<Map<String, Object>> ();    String result = sp.getString(key, "");    try {        JSONArray array = new JSONArray(result);        for (int i = 0; i < array.length(); i++) {            JSONObject itemObject = array.getJSONObject(i);            Map<String, Object> itemMap = new HashMap<String, Object>();            JSONArray names = itemObject.names();            if (names != null) {                for (int j = 0; j < names.length(); j++) {                    String name = names.getString(j);                    String value = itemObject.getString(name);                    itemMap.put(name, value);                }            }            datas.add(itemMap);        }    } catch (JSONException e) {            e.printStackTrace();    }     return datas;}     //清除SharedPreferences中的数据     public void clear(){           editor=sp.edit();           editor.clear();           editor.commit();     }}