Subclassing UIButton with specific UIButtonType

Question

Is there a way to subclass UIButton with specifying its UIButtonType?

I want to use my button class in designer with type already set.

You could Subclass it and inside AwakeFromNib() method, you could set the Type for default. But as I know, correct me if I am wrong, there is no real way to use that Button in Designer, expect u see the default Button and set the class to it. But if u want to draw it by yourself and show that in Designer, there is no way — DirtyNative, Oct 10 '17 at 13:42
`ButtonType` is read only property, so I dont think you can set it. About using in designer, I meant it like you create custom button class and then in designer assign that class to your button. — Naomak, Oct 13 '17 at 07:54

score 1 · Accepted Answer · answered Oct 11 '17 at 02:41

Since UIButtonType is a read-only property, it is not possible to do this.

Only two scenario to subclass UIButton :

Create a subclass of UIbutton and create a public method to wrap it's initial method.

public class MyButton : UIButton
{
    public static MyButton CreateButton()
    {
        return UIButton.FromType(UIButtonType.Custom) as MyButton;
    }
}

Usage:

MyButton button = MyButton.CreateButton();

You can only use it in code not designer in this way

Create a button from designer and rename its class

It will auto generate a subclass of UIButton named CustomButton in you app folder ,and you can assign it to other buttons in designer.

But as i mentioned above, UIButtonType is a read-only property , no way to change it once it's set.
```
public partial class CustomButton : UIButton
{
    public CustomButton (IntPtr handle) : base (handle)
    {
        this.ButtonType = UIButtonType.Custom;    //incorrect , read-only 

        this.Font = UIFont.SystemFontOfSize(10);  //correct, read-write
    }
}
```
RE: Change UIButton type in subclass if button created from storyboard

Thanks for nice answer. Yeah, I have found out both possibilities too. I was only wondering, if there is maybe some other way. I want to use it the way you described in second answer, it's sad you cannot do it like that :/ — Naomak, Oct 13 '17 at 07:52
@cole-xia-msft Hm, actually, can you elaborate more about casting in your first example? Because I'm getting `null` as result value and if I cast it as `(MyButton)UIButton.FromType(UIButtonType.Custom)`, I'm getting _Specified cast is not valid._ So I'm wondering, how this could worK for you? — Naomak, Jun 20 '18 at 13:16
@Naomak My mistake, i read the remark of `UIButton(UIButtonType type);` ,it says `you should avoid subclassing UIButton and then calling into this constructor from your subclass constructor.` so the first solution is also can't be working. — ColeX, Jun 21 '18 at 07:43

Subclassing UIButton with specific UIButtonType

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