Relationship action method between parent class and child class

One, the claim of the random number

1, Arc4random ()%10

2, Arc4random_uniform (10)

Both methods produce the same effect!

Second, the common method of UIView

1, Addsubview

[Self.view Addsubview:newview];

2, nsarrary* Subviews This is an array to return the components in the view

3. Get the last component in the current view

[Self.view.subviews Lastobject];

4. Delete the last component in the current view

[Last Removefromsuperview];

5, (UIView *) Viewwithtag: (int) MyTag

1>, the first is the component that returns the tag value is MyTag

2>, if there is more than one child control has the same tag value, then will first get the position of the previous control where the tag value also contains himself, it is also a tag value

3>, tag default is 0;

Relationship action method between parent class and child class