保存ArrayList至SharedPreferences
其中ArrayList中每个元素为String
List<String> environmentList = new ArrayList<String>();
SharedPreferences.Editor editor = getSharedPreferences("EnvironDataList", MODE_PRIVATE).edit();
editor.putInt("EnvironNums", environmentList.size()); for (int i = 0; i < environmentList.size(); i++) { editor.putString("item_"+i, environmentList.get(i)); } editor.commit();
对应的取出操作为：
List<String> environmentList = new ArrayList<String>();
SharedPreferences preferDataList = getSharedPreferences("EnvironDataList", MODE_PRIVATE);
int environNums = preferDataList.getInt("EnvironNums", 0); for (int i = 0; i < environNums; i++) { String environItem = preferDataList.getString("item_"+i, null); environmentList.add(environItem); }
保存ArrayList至SharedPreferences，其中list的每个元素为自定义对象
1 首先将自定义对象序列化
public class CoordinateAlterSample implements Serializable { private double x; private double y; private String name; public double getX() { return x; } public void setX(double x) { this.x = x; } public double getY() { return y; } public void setY(double y) { this.y = y; } public String getName() { return name; } public void setName(String name) { this.name = name; } }
其次，将list转为json，即可保存到SharedPreferences中
List<CoordinateAlterSample> alterSamples = new ArrayList<CoordinateAlterSample>();
SharedPreferences.Editor editor = getSharedPreferences("AlterSamplesList", MODE_PRIVATE).edit(); Gson gson = new Gson(); String json = gson.toJson(alterSamples); Log.d(TAG, "saved json is "+ json); editor.putString("alterSampleJson", json); editor.commit();
对应的取出操作为：
SharedPreferences preferences = getSharedPreferences("AlterSamplesList", MODE_PRIVATE);
String json = preferences.getString("alterSampleJson", null); if (json != null) { Gson gson = new Gson(); Type type = new TypeToken<List<CoordinateAlterSample>>(){}.getType(); List<CoordinateAlterSample> alterSamples = new ArrayList<CoordinateAlterSample>(); alterSamples = gson.fromJson(json, type); for(int i = 0; i < alterSamples.size(); i++) { Log.d(TAG, alterSamples.get(i).getName()+":" + alterSamples.get(i).getX() + "," + alterSamples.get(i).getY()); }
}
本文转自 一点点征服 博客园博客，原文链接：http://www.cnblogs.com/ldq2016/p/6165513.html，如需转载请自行联系原作者
