像在iPad上一样，检测iOS设备的键盘是否具有“键盘隐藏按钮”？

Question

The default software keyboard on iOS when running on an iPad has a " dismiss " button to hide the keyboard. It's located in the bottom-right corner.

Is there a way to detect specifically this configuration... or that this button exists... aside from checking whether the device is an iPad or not? For example, for devices WITHOUT this button (iPhone/iPod Touch), maybe we would want to add a button outside of the keyboard to do this, but wouldn't want two separate buttons to exist if there was one already on iPad.

Answer 1

I don't think that exist a way to specifically ask if a keyboard supports its, but what you can do is ask the idiom of device:

if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad) {

}
else {

}

Or, since also 6 and 6plus supports that button in landscape you can ask the UITraitCollection of the device in that specific moment, if it is regular the dismiss button on the keyboard will be displayed, but is kind of a strong hypothesis.
Before presenting the keyboard try to check horizontal traits.

if view.traitCollection.horizontalSizeClass == .Regular {
        // has the dismiss button
    }
    else {
        // add an accessory input view
    }

Answer 2

You can set below things

[textField resignFirstResponder];  

or

[textField setReturnKeyType:UIReturnKeyDone];  

and other different types