Make part of UIView visible - ios

Question

I want to add a "shadow" image on my view, but, i want part of my view to still be "visible". You better understand what i want to do, when look on screenshot:
I can add a UIView above my superview, but how could i make specific point "visible"? That actually mean make specific area of a view with different colour or opaque.

Answer 1

For your problem I had a way, try the below example.
1. First storyboard design: I had a UIButton
2. Added black View as a subview
UIView *blackView=[[UIView alloc]initWithFrame:CGRectMake(0, 0, self.view.bounds.size.width, self.view.bounds.size.height)];
blackView.backgroundColor=[UIColor blackColor];
blackView.alpha=0.6f;
[self.view addSubview:blackView];
now result will be:
3. Add one more UIImageView with frame equal to button frame
UIImageView *imageView=[[UIImageView alloc]init];
imageView.frame=self.button.frame; //getting current UIButton bounds
imageView.image=[UIImage imageNamed:#"add_img.png"];
[self.view addSubview:imageView];
Now it looks same as what you want:

Answer 2

You have to add some views. A main view will be the container of your less-alpha view and of the opaque button.
MainView
|
------- UIView with 0.6 alpha
|
------- UIButton with 1 alpha
Indeed, if you change the alpha of the MainView, all subviews will be affected. Here, UIView with 0.6 will have the same frame as MainView but it will not affect UIButton alpha.

Answer 3

Make a new View, a parent View with clear color background. Add the black view and the button to the parent view and set the black view's alpha to 0.6 or whatever.

Answer 4

Try this:
Make a UIView called buttonBackgroundView, give it a black color and then
[self.view addsubView:buttonBackgroundView];
now make a UIView named plusView (or UIButton if this plus sign is a button) then
[self.view addsubView:plusView];
After that, give the alpha to the buttonBackgroundView
buttonBackgroundView.alpha = 0.6;
Happy coding!