SharedPreferences保存List<Map<String, Object»数据
众所周知SharedPreferences是以key-vlues存储的xml文件格式，业务需求需要将List<Map<String, Object»数据格式的数据保存下来，以便下次读取显示，如果用sqlite来保存的话有点杀鸡用牛刀的感觉，毕竟数据量并不大。
下面记录一下如何用SharedPreferences保存List<Map<String, Object»数据
解决方案：
先将数据转化成JSON,然后保存字符串，取出时再将JSON转化成数组
保存数据
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<Map.Entry<String, Object>> iterator = itemMap.entrySet().iterator();
JSONObject object = new JSONObject();
while (iterator.hasNext()) {
Map.Entry<String, Object> entry = iterator.next();
try {
object.put(entry.getKey(), entry.getValue());
} catch (JSONException e) {
}
}
mJsonArray.put(object);
}
SharedPreferences sp = context.getSharedPreferences("err_port", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sp.edit();
editor.putString(key, mJsonArray.toString());
editor.commit();
}
读取数据
public List<Map<String, Object>> getInfo(Context context, String key) {
List<Map<String, Object>> datas = new ArrayList<Map<String, Object>>();
SharedPreferences sp = context.getSharedPreferences("err_port", Context.MODE_PRIVATE);
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) {
}
return datas;
}
