占位符文本不以编程方式创建的UITextField为中心

Question

I am creating a UITextField programmatically and placing it inside a UIView. The font size is set to 15.0f (system font). But the placeholder that appears is not centered in the text view. Any one know how to resolve this?

I found some references on SO for blurred text etc and tried setting the frame of the textfield with integer values, but it doesn't make a difference.

UITextField *txtField = [[UITextField alloc] initWithFrame:CGRectMake(5.0f, 6.0f, 278.0f, 32.0f)];
[txtField setPlaceholder:@"My placeholder"];
[txtField setFont:[UIFont systemFontOfSize:15.0]];
[txtField setBorderStyle:UITextBorderStyleRoundedRect];
[txtField setAutocorrectionType:UITextAutocorrectionTypeNo];
[txtField setAutocapitalizationType:UITextAutocapitalizationTypeNone];
[txtField setKeyboardType:UIKeyboardTypeEmailAddress];
[txtField setReturnKeyType:UIReturnKeyDone];
[txtField setClearButtonMode:UITextFieldViewModeWhileEditing];

Thank you for any help

Note: I mean that the text is not centered vertically in the textfield (it is a bit towards the top). So setting the text alignment is not the solution.

Adding an image of the issue for clarification - as seen in the image, the placeholder text is more towards the top and not in the center vertically.

Answer 1

You need to add:

txtField.textAlignment = NSTextAlignmentCenter; // Pre-iOS6 SDK: UITextAlignmentCenter

Keep in mind, this adjusts both the alignment of the placeholder text as well as the text the user will enter in.

How to center vertically

Since the original question was updated to request how to vertically align the placeholder text and that answer is buried in the comments, here is how to do that:

txtField.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;

Answer 2

This does not work as expected on iOS7. On iOS7 you will have to override TextField class and

- (void) drawPlaceholderInRect:(CGRect)rect

method.

Like this:

- (void) drawPlaceholderInRect:(CGRect)rect
{
    [[UIColor blueColor] setFill];
    CGRect placeholderRect = CGRectMake(rect.origin.x, (rect.size.height- self.font.pointSize)/2, rect.size.width, self.font.pointSize);
    [[self placeholder] drawInRect:placeholderRect withFont:self.font lineBreakMode:NSLineBreakByWordWrapping alignment:self.textAlignment];
}

Works for both iOS7 and earlier versions.

Answer 3

I was using just the color, but we need to set the font as well.

This one worked for me:

[[UITextField appearanceWhenContainedIn:[UISearchBar class], nil] setDefaultTextAttributes:
@{
     NSForegroundColorAttributeName:[UIColor whiteColor], 
     NSFontAttributeName: [UIFont systemFontOfSize:12]
}];

Answer 4

Changing the minimum line height using NSParagraphStyle was the only solution that worked for me:

    NSMutableParagraphStyle *style = [self.addressBar.defaultTextAttributes[NSParagraphStyleAttributeName] mutableCopy];
style.minimumLineHeight = self.addressBar.font.lineHeight - (self.addressBar.font.lineHeight - placeholderFont.lineHeight) / 2.0;

self.addressBar.attributedPlaceholder = [[NSAttributedString alloc] initWithString:@"Placeholder text" attributes:@{
     NSForegroundColorAttributeName: [UIColor colorWithRed:79/255.0f green:79/255.0f blue:79/255.0f alpha:0.5f],
     NSFontAttributeName : placeholderFont,
     NSParagraphStyleAttributeName : style
}];