my app has a UITextfield that must use system keyboard input, but i have no idea
<p>my app has a <code>UITextfield</code>, that must be use system number keyboard, this <code>UITextfield</code> is be used to number, can't input punctuation and alphabet, </p>

<p>some other input method can't limit </p>

<p>user can tap "返回", and keyboard change to this style <a href="https://i.stack.imgur.com/NtsaC.png" rel="nofollow noreferrer">like this</a></p>

<p><a href="https://i.stack.imgur.com/gDPnU.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/gDPnU.png" alt="enter image description here"></a></p>

<p>so i must use this system keyboard <a href="https://i.stack.imgur.com/cew73.png" rel="nofollow noreferrer">system number keyboard</a></p>

<p><a href="https://i.stack.imgur.com/xhUrf.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/xhUrf.png" alt="enter image description here"></a></p>

<p>I want someway, force one <code>ViewContoller</code> Or <code>TextField</code>, use system number keyboard</p>