在StackOverFlow寻找问题时,发现一个好东西,也是一直困扰自己的小bug。其实是很基础的东西啦。
引用http://stackoverflow.com/questions/10102151/whats-the-difference-between-this-and-activity-this
For example:
Intent intent = new Intent(this, SecondActivity.class);
eclipse error: The method setClass(Context, Class) in the type Intent is not applicable for the arguments (FirstActivity.ClickEvent, Class)
Intent intent = new Intent(FirstActivity.this, SecondActivity.class);
But that will be correct. Anybody can explain the difference between those two ? Thanks.
最高票答案:
this
refers to your current object. In your case you must have implemented the intent in an inner class ClickEvent, and thats what it points to.
Activity.this
points to the instance of the Activity you are currently in.
翻译过来就是this是你当前对象的引用,在你的例子中你肯定在内部类ClickEvent里面实现intent,他指向的是ClickEvent,而不是你要传入的Activity。
Activity.this指向你所填写的Activity名字的一个实例,也是引用。
总结:
this作为当前对象,直接用在Activity里面是没问题的,当this在匿名内部类中使用,当前的对象就变成new的内部类,而你传入的东西如果是整个Activity的话,就要Activity.this了。
所以保险起见,还是统一用Activity.this比较好。