android中 创建 删除 清空 SharedPreferences

1.创建文件,保存信息

     SharedPreferences sp=getSharedPreferences("user",MODE_PRIVATE);

     Editor editor=sp.edit(); 
     editor.putFloat("deltaX", (float) deltaX);

     editor.putString("key","value");
     editor.commit();

2.删除与清空文件信息

          //删除文件

         File file= new File("/data/data/"+getPackageName().toString()+"/shared_prefs","user.xml");
                  if(file.exists())

                 {
                          file.delete();
                          Toast.makeText(TestActivity.this, "删除成功", Toast.LENGTH_LONG).show();
                  }

          //清空文件

         SharedPreferences sp=getSharedPreferences("user",MODE_PRIVATE);

         if(sp!=null){
         sp.edit().clear().commit();
         Toast.makeText(ArcgisTDZLActivity.this, "数据已清空", Toast.LENGTH_LONG).show();

 

          最简单的获取值：

                      String key=sp.getString("key","defvalue");
         }