Android开发经常会操作SharedPreferences，所以封装一个工具类供大家使用。源码如下：
package com.ml512.common.utils;
import android.content.Context;
import android.content.SharedPreferences;
import android.text.TextUtils;
import java.util.Set;
/**
* 统一的SharedPreferences操作类
* <p>
* create by malong at 2018/6/25 15:08
*/
public class SharedPreferencesHelper {
private static final String TAG = SharedPreferencesHelper.class.getSimpleName();
private static SharedPreferences mSharedPreferences = null;
/**
* 初始化
*
* @param applicationContext
* @param spName
*/
public static void init(Context applicationContext, String spName) {
if (TextUtils.isEmpty(spName)) {
throw new NullPointerException("When SharedPreferencesHelper init, SharedPreferences name is null!");
}
if (applicationContext == null) {
throw new NullPointerException("When SharedPreferencesHelper init, applicationContext is null!");
}
mSharedPreferences = applicationContext.getSharedPreferences(spName, Context.MODE_PRIVATE);
}
/**
* 删除key
*
* @param key The name of the preference to remove.
*/
public static void removeKey(String key) {
if (mSharedPreferences != null) {
SharedPreferences.Editor editor = mSharedPreferences.edit();
editor.remove(key);
editor.apply();
} else {
Log.e(TAG, "mSharedPreferences is null");
}
}
public static void clear(){
if (mSharedPreferences != null) {
SharedPreferences.Editor editor = mSharedPreferences.edit();
editor.clear();
editor.apply();
} else {
Log.e(TAG, "mSharedPreferences is null");
}
}
public static void applyInt(String key, int value) {
applyKeyValue(key, value);
}
public static void applyLong(String key, long value) {
applyKeyValue(key, value);
}
public static void applyFloat(String key, float value) {
applyKeyValue(key, value);
}
public static void applyBoolean(String key, boolean value) {
applyKeyValue(key, value);
}
public static void applyString(String key, String value) {
if (null == value) {//防止传入null时无法判断存储类型
applyKeyValue(key, "");
return;
}
applyKeyValue(key, value);
}
public static void applyStringSet(String key, Set<String> defValue) {
if (mSharedPreferences != null && null == defValue) {//防止传入null时无法判断存储类型
mSharedPreferences.edit().putStringSet(key, null).apply();
}
commitKeyValue(key, defValue);
}
public static boolean commitInt(String key, int value) {
return commitKeyValue(key, value);
}
public static boolean commitLong(String key, long value) {
return commitKeyValue(key, value);
}
public static boolean commitFloat(String key, float value) {
return commitKeyValue(key, value);
}
public static boolean commitBoolean(String key, boolean value) {
return commitKeyValue(key, value);
}
public static boolean commitString(String key, String value) {
if (null == value) {//防止传入null时无法判断存储类型
return commitKeyValue(key, "");
}
return commitKeyValue(key, value);
}
public static boolean commitStringSet(String key, Set<String> defValue) {
if (mSharedPreferences != null && null == defValue) {//防止传入null时无法判断存储类型
return mSharedPreferences.edit().putStringSet(key, null).commit();
}
return commitKeyValue(key, defValue);
}
public static int getInt(String key, int defValue) {
return (int) getValue(key, defValue);
}
public static long getLong(String key, long defValue) {
return (long) getValue(key, defValue);
}
public static float getFloat(String key, float defValue) {
return (float) getValue(key, defValue);
}
public static boolean getBoolean(String key, boolean defValue) {
return (boolean) getValue(key, defValue);
}
public static String getString(String key, String defValue) {
if (null == defValue) {//防止传入null时无法判断存储类型
return (String) getValue(key, "");
}
return (String) getValue(key, defValue);
}
public static Set<String> getStringSet(String key, Set<String> defValue) {
if (mSharedPreferences != null && null == defValue) {//防止传入null时无法判断存储类型
return mSharedPreferences.getStringSet(key, null);
}
return (Set<String>) getValue(key, defValue);
}
/**
* 异步提交保存
* 注：不提供该方法给外部是因为，传入的是Object，类型表意不够明确，使用易误导。
*
* @param key
* @param value
* @return
*/
private static void applyKeyValue(String key, Object value) {
if (mSharedPreferences == null) {
Log.e(TAG, "mSharedPreferences is null");
return;
}
SharedPreferences.Editor editor = setEditor(key, value);
editor.apply();
}
/**
* 立即提交保存，立即生效，立即返回保存到磁盘的成功与否
* 注：不提供该方法给外部是因为，传入的是Object，类型表意不够明确，使用易误导。
*
* @param key
* @param value
* @return
*/
private static boolean commitKeyValue(String key, Object value) {
if (mSharedPreferences == null) {
Log.e(TAG, "mSharedPreferences is null");
return false;
}
SharedPreferences.Editor editor = setEditor(key, value);
return editor.commit();
}
/**
* 统一保存处理
*
* @param key
* @param value
* @return
*/
private static SharedPreferences.Editor setEditor(String key, Object value) {
SharedPreferences.Editor editor = mSharedPreferences.edit();
if (value instanceof String) {
editor.putString(key, (String) value);
} else if (value instanceof Integer) {
editor.putInt(key, (Integer) value);
} else if (value instanceof Long) {
editor.putLong(key, (Long) value);
} else if (value instanceof Float) {
editor.putFloat(key, (Float) value);
} else if (value instanceof Boolean) {
editor.putBoolean(key, (Boolean) value);
} else if (value instanceof Set) {
editor.putStringSet(key, (Set<String>) value);
}
return editor;
}
/**
* 统一获取处理
*
* @param key
* @param defValue
* @return
*/
private static Object getValue(String key, Object defValue) {
if (mSharedPreferences == null) {
Log.e(TAG, "mSharedPreferences is null");
return defValue;
}
if (defValue instanceof String) {
return mSharedPreferences.getString(key, (String) defValue);
} else if (defValue instanceof Integer) {
return mSharedPreferences.getInt(key, (Integer) defValue);
} else if (defValue instanceof Long) {
return mSharedPreferences.getLong(key, (Long) defValue);
} else if (defValue instanceof Float) {
return mSharedPreferences.getFloat(key, (Float) defValue);
} else if (defValue instanceof Boolean) {
return mSharedPreferences.getBoolean(key, (Boolean) defValue);
} else if (defValue instanceof Set) {
return mSharedPreferences.getStringSet(key, (Set<String>) defValue);
}
return defValue;
}
}
使用方法：
在application中的 onCreate() 初始化
SharedPreferencesHelper.init(applicationContext,spName);调用如下：
Set<String> mySet = new HashSet<>();
mySet.add("kk");
mySet.add("kdk");
/**
* 通过apply()方式异步存入数据
*/
SharedPreferencesHelper.applyInt("int_key", 1);
SharedPreferencesHelper.applyLong("long_key", 1L);
SharedPreferencesHelper.applyFloat("float_key", 1.0f);
SharedPreferencesHelper.applyString("str_key", "1");
SharedPreferencesHelper.applyBoolean("boolean_key", true);
SharedPreferencesHelper.applyStringSet("set_test",mySet);
/**
* 通过commit()方式存入数据
*/
SharedPreferencesHelper.commitInt("int_key", 1);
SharedPreferencesHelper.commitLong("long_key", 1L);
SharedPreferencesHelper.commitFloat("float_key", 1.0f);
SharedPreferencesHelper.commitString("str_key", "1");
SharedPreferencesHelper.commitBoolean("boolean_key", true);
SharedPreferencesHelper.commitStringSet("set_test",mySet);
/**
* 获取数据
*/
SharedPreferencesHelper.getInt("int_key", 1);
SharedPreferencesHelper.getLong("long_key", 1L);
SharedPreferencesHelper.getFloat("float_key", 1.0f);
SharedPreferencesHelper.getString("str_key", "1");
SharedPreferencesHelper.getBoolean("boolean_key", true);
SharedPreferencesHelper.getStringSet("set_test", null);
/**
* 清空
*/
SharedPreferencesHelper.clear();
/**
* 删除
*/
SharedPreferencesHelper.removeKey("remove_key");