Android本地化全局对象的实践(2)——SharePreferences
个人博客CoorChice，https://chenbingx.github.io/ ，最新文章将会首发CoorChice的博客，欢迎探索哦 ! 同时，搜索微信公众号CoorChice，或扫描文章末尾二维码，可以关注我的微信公众号。同期文章也将会优先推送到微信公众号中，以提醒您有新鲜文章出炉。 上一篇讲到了使用File的方式来本地化全局对象，它适合体量较大的全局对象。对于一些体量较小的全局，并且对安全性有要求的对象，可以使用SharePreference来进行对像的本地化。 注意，这种方式适合较小的对象，较大的对象还是应该选用File的方式。 使用实例 //全局对象和上一篇中一样 public class User implements Serializable, Cloneable { public static final long serialVersionUID = 1L; private int userId; private String userNikeName; private String userRealName; private int userLevel; private int vipLevel; public User() { } public User(int userId, String userNikeName, String userRealName, int userLevel, int vipLevel) { this.userId = userId; this.userNikeName = userNikeName; this.userRealName = userRealName; this.userLevel = userLevel; this.vipLevel = vipLevel; } public int getUserId() { return userId; } public void setUserId(int userId) { this.userId = userId; } public String getUserNikeName() { return userNikeName; } public void setUserNikeName(String userNikeName) { this.userNikeName = userNikeName; } public String getUserRealName() { return userRealName; } public void setUserRealName(String userRealName) { this.userRealName = userRealName; } public int getUserLevel() { return userLevel; } public void setUserLevel(int userLevel) { this.userLevel = userLevel; } public int getVipLevel() { return vipLevel; } public void setVipLevel(int vipLevel) { this.vipLevel = vipLevel; } protected User(Parcel in) { this.userId = in.readInt(); this.userNikeName = in.readString(); this.userRealName = in.readString(); this.userLevel = in.readInt(); this.vipLevel = in.readInt(); } } //下面两个方法实现了Object对象和编码方式为Base64的字符串的互相转换 public static final String ObjectToBase64String(Object object) throws IOException { ByteArrayOutputStream baos = new ByteArrayOutputStream(); ObjectOutputStream oos = new ObjectOutputStream(baos); oos.writeObject(object); String base64String = Base64.encodeToString(baos.toByteArray(), Base64.DEFAULT); //采用Base64编码方式编码对象生成的字节数组为字符串 if (oos != null){ oos.close(); } if (baos != null){ baos.close(); } return base64String; } public static final <T> T Base64StringToObject(String base64String, Class<T> clazz) throws IOException, ClassNotFoundException { byte[] bytes = Base64.decode(base64String, Base64.DEFAULT); //解码 ByteArrayInputStream bais = new ByteArrayInputStream(bytes); ObjectInputStream ois = new ObjectInputStream(bais); T t = (T) ois.readObject(); if (ois != null) { ois.close(); } if (bais != null) { bais.close(); } return t; } //下面两个方法是进行存取的 public class SharePreferencesUtils { public static final void saveObject(@NonNull Context context, String key, @NonNull Object object) throws IOException { SharedPreferences sp = context.getSharedPreferences(key, Context.MODE_PRIVATE); SharedPreferences.Editor editor = sp.edit(); String base64String = AppUtils.ObjectToBase64String(object); editor.putString(key, base64String); editor.commit(); } public static final <T> T restoreObject(@NonNull Context context, String key, Class<T> clazz) throws IOException, ClassNotFoundException { SharedPreferences sp = context.getSharedPreferences(key, Context.MODE_PRIVATE); String base64String = sp.getString(key, ""); T t = null; if (!base64String.equals("")){ t = AppUtils.Base64StringToObject(base64String, clazz); } return t; } } //现在就可以开始使用啦 private void saveUserToSP(User user){ try { SharePreferencesUtils.saveObject(this, AppConstant.USER_KEY,user); } catch (IOException e) { e.printStackTrace(); } } private User restoreUserFromSP(){ User user = null; try { user = SharePreferencesUtils.restoreObject(this,AppConstant.USER_KEY,User.class); } catch (IOException | ClassNotFoundException e) { e.printStackTrace(); } return user; } CoorChice的公众号
