Android修改默认SharedPreferences文件的路径，SharedPreferences常用工具类

 import android.app.Activity;
 import android.content.Context;
 import android.content.ContextWrapper;
 import android.content.SharedPreferences;

 import com.imageviewpager.language.MyApplication;

 import java.io.File;
 import java.lang.reflect.Field;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.util.Map;

 public class SPUtil {

     /** debug 环境下允许修改 sp文件的路径 */
     public static final boolean isDebug = true;
     /** 修改以后的sp文件的路径 MyApplication.getContext().getExternalFilesDir(null).getAbsolutePath()=/sdcard/Android/%package_name%/file */
     public static final String FILE_PATH = MyApplication.getContext().getExternalFilesDir(null).getAbsolutePath();

     /**
      * 保存数据
      *
      * @param context
      * @param fileName 文件名, 不需要".xml"
      * @param keyName
      * @param value
      */
     public static void put(Context context, String fileName, String keyName, Object value) {
         SharedPreferences.Editor editor = getSharedPreferences(context, fileName).edit();
         if (value instanceof String) {
             editor.putString(keyName, (String) value);
         } else if (value instanceof Integer) {
             editor.putInt(keyName, (Integer) value);
         } else if (value instanceof Boolean) {
             editor.putBoolean(keyName, (Boolean) value);
         } else if (value instanceof Float) {
             editor.putFloat(keyName, (Float) value);
         } else if (value instanceof Long) {
             editor.putLong(keyName, (Long) value);
         } else {
             editor.putString(keyName, value.toString());
         }

         SharedPreferencesCompat.apply(editor);
     }

     /**
      * 获取数据
      *
      * @param context
      * @param fileName
      * @param keyName
      * @param defaultValue 默认值
      * @return
      */
     public static Object get(Context context, String fileName, String keyName, Object defaultValue) {
         SharedPreferences sp = getSharedPreferences(context, fileName);
         if (defaultValue instanceof String) {
             return sp.getString(keyName, (String) defaultValue);
         } else if (defaultValue instanceof Integer) {
             return sp.getInt(keyName, (Integer) defaultValue);
         } else if (defaultValue instanceof Boolean) {
             return sp.getBoolean(keyName, (Boolean) defaultValue);
         } else if (defaultValue instanceof Float) {
             return sp.getFloat(keyName, (Float) defaultValue);
         } else if (defaultValue instanceof Long) {
             return sp.getLong(keyName, (Long) defaultValue);
         }
         return null;
     }

     /**
      * 移除某个key值对应的值
      *
      * @param context
      * @param fileName
      * @param keyName
      */
     public static void remove(Context context, String fileName, String keyName) {
         SharedPreferences.Editor editor = getSharedPreferences(context, fileName).edit();
         editor.remove(keyName);
         SharedPreferencesCompat.apply(editor);
     }

     /** 清除所有数据 */
     public static void clear(Context context, String fileName) {
         SharedPreferences.Editor editor = getSharedPreferences(context, fileName).edit();
         editor.clear();
         SharedPreferencesCompat.apply(editor);
     }

     /**
      * 查询某个key是否已经存在
      *
      * @param context
      * @param keyName
      * @return
      */
     public static boolean contains(Context context, String fileName, String keyName) {
         return getSharedPreferences(context, fileName).contains(keyName);
     }

     /** 返回所有的键值对 */
     public static Map<String, ?> getAll(Context context, String fileName) {
         return getSharedPreferences(context, fileName).getAll();
     }

     /** 创建一个解决SharedPreferencesCompat.apply方法的一个兼容类 */
     private static class SharedPreferencesCompat {
         private static final Method sApplyMethod = findApplyMethod();

         /** 反射查找apply的方法 */
         @SuppressWarnings({"unchecked", "rawtypes"})
         private static Method findApplyMethod() {
             try {
                 Class clz = SharedPreferences.Editor.class;
                 return clz.getMethod("apply");
             } catch (NoSuchMethodException e) {
             }

             return null;
         }

         /** 如果找到则使用apply执行，否则使用commit */
         public static void apply(SharedPreferences.Editor editor) {
             try {
                 if (sApplyMethod != null) {
                     sApplyMethod.invoke(editor);
                     return;
                 }
             } catch (IllegalArgumentException e) {
             } catch (IllegalAccessException e) {
             } catch (InvocationTargetException e) {
             }
             editor.commit();
         }
     }

     /**
      * @param context
      * @param fileName
      * @return isDebug = 返回修改路径(路径不存在会自动创建)以后的 SharedPreferences :%FILE_PATH%/%fileName%.xml<br/>
      * !isDebug = 返回默认路径下的 SharedPreferences : /data/data/%package_name%/shared_prefs/%fileName%.xml
      */
     private static SharedPreferences getSharedPreferences(Context context, String fileName) {
         if (isDebug) {
             try {
                 // 获取ContextWrapper对象中的mBase变量。该变量保存了ContextImpl对象
                 Field field = ContextWrapper.class.getDeclaredField("mBase");
                 field.setAccessible(true);
                 // 获取mBase变量
                 Object obj = field.get(context);
                 // 获取ContextImpl。mPreferencesDir变量，该变量保存了数据文件的保存路径
                 field = obj.getClass().getDeclaredField("mPreferencesDir");
                 field.setAccessible(true);
                 // 创建自定义路径
                 File file = new File(FILE_PATH);
                 // 修改mPreferencesDir变量的值
                 field.set(obj, file);
                 // 返回修改路径以后的 SharedPreferences :%FILE_PATH%/%fileName%.xml
                 return context.getSharedPreferences(fileName, Activity.MODE_PRIVATE);
             } catch (NoSuchFieldException e) {
                 e.printStackTrace();
             } catch (IllegalArgumentException e) {
                 e.printStackTrace();
             } catch (IllegalAccessException e) {
                 e.printStackTrace();
             }
         }
         // 返回默认路径下的 SharedPreferences : /data/data/%package_name%/shared_prefs/%fileName%.xml
         return context.getSharedPreferences(fileName, Context.MODE_PRIVATE);
     }

 }

转自：http://www.cnblogs.com/Westfalen/p/5380737.html