OnCreate(@nullable Bundle savedInstances);中的@nullable有什么用？
What is the use of @nullable in OnCreate(@nullable Bundle savedInstances);?
@nullable 的用途是什么，在什么情况下不使用 @nullable 会成为 onCreate(@nullable Bundle SavedInstances);
中的问题
Nullable
Denotes that a parameter, field or method return value can be null.
When decorating a method call parameter, this denotes that the
parameter can legitimately be null and the method will gracefully deal
with it. Typically used on optional parameters.
When decorating a method, this denotes the method might legitimately
return null.
This is a marker annotation and it has no specific attributes.
https://developer.android.com/reference/android/support/annotation/Nullable.html
您可以从 OnCreate(@nullable Bundle savedInstances); 安全地 ignore/remove @nullable 因为它表示参数，Bundle 可以为 null 并且它在运行时没有作用 See the Documentation here for more details
@nullable 的用途是什么，在什么情况下不使用 @nullable 会成为 onCreate(@nullable Bundle SavedInstances);
Nullable
Denotes that a parameter, field or method return value can be null.
When decorating a method call parameter, this denotes that the parameter can legitimately be null and the method will gracefully deal with it. Typically used on optional parameters.
When decorating a method, this denotes the method might legitimately return null.
This is a marker annotation and it has no specific attributes.
https://developer.android.com/reference/android/support/annotation/Nullable.html
您可以从 OnCreate(@nullable Bundle savedInstances); 安全地 ignore/remove @nullable 因为它表示参数，Bundle 可以为 null 并且它在运行时没有作用 See the Documentation here for more details