Android SharedPreferences保存集合(List类型)
安卓项目中会经常遇到使用SharedPreferences的情况,如果要保存的类型是List,可以这样实现:
1.定义MessageModel .java
public class MessageModel implements Serializable{
private String name;
private String title;
private String body;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getBody() {
return body;
}
public void setBody(String body) {
this.body = body;
}
}
2.集合中添加数据并保存:
List namelist = new ArrayList<>();
MessageModel messageModel = new MessageModel();
messageModel.setName(name.getText().toString());
messageModel.setTitle(title.getText().toString());
messageModel.setBody(body.getText().toString());
namelist.add(messageModel);
SharedPreferences sp = mBaseActivity.getSharedPreferences("SP_NewUserModel_List", Activity.MODE_PRIVATE);//创建sp对象
Gson gson = new Gson();
String jsonStr=gson.toJson(namelist); //将List转换成Json
SharedPreferences.Editor editor = sp.edit() ;
editor.putString("KEY_NewUserModel_LIST_DATA", jsonStr) ; //存入json串
editor.commit() ; //提交
3.读取数据
SharedPreferences sp = mBaseActivity.getSharedPreferences("SP_NewUserModel_List",Activity.MODE_PRIVATE);//创建sp对象,如果有key为"SP_PEOPLE"的sp就取出
String peopleListJson = sp.getString("KEY_NewUserModel_LIST_DATA",""); //取出key为"KEY_PEOPLE_DATA"的值,如果值为空,则将第二个参数作为默认值赋值
if(peopleListJson!="") //防空判断
{
Gson gson = new Gson();
namelist = gson.fromJson(peopleListJson, new TypeToken<List<MessageModel>>() {}.getType()); //将json字符串转换成List集合
}