UIButton not clickable when custom view called

I am new to iPhone development,I need help in understanding the below,as I am able to create newView using the following

UIView *newView=[[UIView alloc]initWithFrame:CGRectMake(0, 0, 80, 30)]; 
newView.backgroundColor=[UIColor clearColor];
UIButton *newViewBtn=[UIButton buttonWithType:UIButtonTypeRoundedRect];


newViewBtn.frame = CGRectMake(newView.frame.origin.x+5,
                            newView.frame.origin.y+5,60,20);
[newView addSubview:newViewBtn];
[self.view addSubview:newView]; 

Above code is working without any problem. But when I try to create the view using the following, view is created alright, but the button on the view is not clickable.

int randNumX = arc4random() % 150;
int randNumY = arc4random() % 200;
UIView newView=[[UIView alloc]init];
newView.frame =CGRectMake(randNumX, randNumY, 80, 30);

newView.backgroundColor=[UIColor clearColor];

UIButton *newViewBtn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
newViewBtn.frame  = CGRectMake(newView.frame.origin.x+5
                         ,newView.frame.origin.y+5,60,20);
[newView addSubview:newViewBtn];
[self.view addSubview:newView];

and there is one another scenario if change the following code

 newViewBtn.frame = CGRectMake(newView.frame.origin.x+5
                          ,newView.frame.origin.y+5,60,20);

with the code below app crashes

 newViewBtn.frame =CGRectMake(randNumX+5,randNumY+5,60,20);

Any help will be greatly appreciated,thanks in advance.

I have added the following code already

     newViewBtn addTarget:self action:@selector(btnclick:)forControlEvents:UIControlEventTouchUpInside];

     -(void)btnclick:(id)sender
     {
       //my code
     }

It is working in the first case:

My main concern here is when the newView is draw ,why the button on this view is not clickable

Here the problem is the Line below ,As the new child view must be according to the parent view

    newViewBtn.frame =CGRectMake(randNumX+5,randNumY+5,60,20);

writting the above as below solved the problem

    newViewBtn.frame =CGRectMake(5,5,60,20);