How to change UIPickerView height

It seems obvious that Apple doesn't particularly invite mucking with the default height of the UIPickerView, but I have found that you can achieve a change in the height of the view by taking complete control and passing a desired frame size at creation time, e.g:

smallerPicker = [[UIPickerView alloc] initWithFrame:CGRectMake(0.0, 0.0, 320.0, 120.0)];

You will discover that at various heights and widths, there are visual glitches. Obviously, these glitches would either need to be worked around somehow, or choose another size that doesn't exhibit them.

I have found that you can edit the size of the UIPickerView - just not with interface builder. open the .xib file with a text editor and set the size of the picker view to whatever you want. Interface builder does not reset the size and it seems to work. I'm sure apple locked the size for a reason so you'll have to experiment with different sizes to see what works.

I wasn't able to follow any of the above advice.

I watched multiple tutorials and found this one the most beneficial:

I added the following code to set the new height inside the "viewDidLoad" method, which worked in my app.

UIPickerView *picker = [[UIPickerView alloc] initWithFrame:CGRectMake(0.0, 0.0, 320.0, 120.0)]; 
[self.view addSubview:picker];
picker.delegate = self;
picker.dataSource = self;

Hope this was helpful!

As mentioned above UIPickerView is now resizable. I just want to add though that if you want to change the pickerView's height in a tableView Cell, I didn't have any success with setting the height anchor to a constant. However, using lessThanOrEqualToConstant seems to work.

 class PickerViewCell: UITableViewCell {

    let pickerView = UIPickerView()

    func setup() {

        // call this from however you initialize your cell

        self.contentView.addSubview(self.pickerView)
        self.pickerView.translatesAutoresizingMaskIntoConstraints = false

        let constraints: [NSLayoutConstraint] = [
            // pin the pickerView to the contentView's layoutMarginsGuide

            self.pickerView.leadingAnchor.constraint(equalTo: self.contentView.layoutMarginsGuide.leadingAnchor),
            self.pickerView.topAnchor.constraint(equalTo: self.contentView.layoutMarginsGuide.topAnchor),
            self.pickerView.trailingAnchor.constraint(equalTo: self.contentView.layoutMarginsGuide.trailingAnchor),
            self.pickerView.bottomAnchor.constraint(equalTo: self.contentView.layoutMarginsGuide.bottomAnchor),

            // set the height using lessThanOrEqualToConstant
            self.pickerView.heightAnchor.constraint(lessThanOrEqualToConstant: 100)
        ]

        NSLayoutConstraint.activate(constraints)
     }

 }

As far as I know, it's impossible to shrink the UIPickerView. I also haven't actually seen a shorter one used anywhere. My guess is that it was a custom implementation if they did manage to shrink it.

If you want to create your picker in IB, you can post-resize it to a smaller size. Check to make sure it still draws correctly though, as there comes a point where it looks heinous.

for iOS 5:

if you take a quick look at the UIPickerView Protocol Reference

you'll find

– pickerView:rowHeightForComponent:
– pickerView:widthForComponent:

I think is the first one you're looking for