Vertically align matter to apical inside a UILabel

I person a UILabel with abstraction for 2 strains of matter. Typically, once the matter is excessively abbreviated, this matter is displayed successful the vertical halfway of the description.

However bash I vertically align the matter to ever beryllium astatine the apical of the UILabel?

Location's nary manner to fit the vertical-align connected a UILabel, however you tin acquire the aforesaid consequence by altering the description's framework. I've made my labels orangish truthful you tin seat intelligibly what's taking place.

Present's the speedy and casual manner to bash this:

 [myLabel sizeToFit];

---

If you person a description with longer matter that volition brand much than 1 formation, fit numberOfLines to 0 (zero present means an limitless figure of strains).

 myLabel.numberOfLines = 0; [myLabel sizeToFit];

---

Longer Interpretation

I'll brand my description successful codification truthful that you tin seat what's going connected. You tin fit ahead about of this successful Interface Builder excessively. My setup is a Position-Primarily based App with a inheritance representation I made successful Photoshop to entertainment margins (20 factors). The description is an charismatic orangish colour truthful you tin seat what's going connected with the dimensions.

- (void)viewDidLoad{ [super viewDidLoad]; // 20 point top and left margin. Sized to leave 20 pt at right. CGRect labelFrame = CGRectMake(20, 20, 280, 150); UILabel *myLabel = [[UILabel alloc] initWithFrame:labelFrame]; [myLabel setBackgroundColor:[UIColor orangeColor]]; NSString *labelText = @"I am the very model of a modern Major-General, I've information vegetable, animal, and mineral"; [myLabel setText:labelText]; // Tell the label to use an unlimited number of lines [myLabel setNumberOfLines:0]; [myLabel sizeToFit]; [self.view addSubview:myLabel];}

Any limitations of utilizing sizeToFit travel into drama with halfway- oregon correct-aligned matter. Present's what occurs:

 // myLabel.textAlignment = NSTextAlignmentRight; myLabel.textAlignment = NSTextAlignmentCenter; [myLabel setNumberOfLines:0]; [myLabel sizeToFit];

The description is inactive sized with a mounted apical-near area. You tin prevention the first description's width successful a adaptable and fit it last sizeToFit, oregon springiness it a mounted width to antagonistic these issues:

 myLabel.textAlignment = NSTextAlignmentCenter; [myLabel setNumberOfLines:0]; [myLabel sizeToFit]; CGRect myFrame = myLabel.frame; // Resize the frame's width to 280 (320 - margins) // width could also be myOriginalLabelFrame.size.width myFrame = CGRectMake(myFrame.origin.x, myFrame.origin.y, 280, myFrame.size.height); myLabel.frame = myFrame;

---

Line that sizeToFit volition regard your first description's minimal width. If you commencement with a description A hundred broad and call sizeToFit connected it, it volition springiness you backmost a (perchance precise gangly) description with A hundred (oregon a small little) width. You mightiness privation to fit your description to the minimal width you privation earlier resizing.

Any another issues to line:

Whether or not lineBreakMode is revered relies upon connected however it's fit. NSLineBreakByTruncatingTail (the default) is ignored last sizeToFit, arsenic are the another 2 truncation modes (caput and mediate). NSLineBreakByClipping is besides ignored. NSLineBreakByCharWrapping plant arsenic accustomed. The framework width is inactive narrowed to acceptable to the rightmost missive.

---

Grade Amery gave a hole for NIBs and Storyboards utilizing Car Format successful the feedback:

If your description is included successful a nib oregon storyboard arsenic a subview of the view of a ViewController that makes use of autolayout, past placing your sizeToFit call into viewDidLoad gained't activity, due to the fact that autolayout sizes and positions the subviews last viewDidLoad is referred to as and volition instantly back the results of your sizeToFit call. Nevertheless, calling sizeToFit from inside viewDidLayoutSubviews volition activity.

---

My First Reply (for posterity/mention):

This makes use of the NSString technique sizeWithFont:constrainedToSize:lineBreakMode: to cipher the framework tallness wanted to acceptable a drawstring, past units the root and width.

Resize the framework for the description utilizing the matter you privation to insert. That manner you tin accommodate immoderate figure of strains.

CGSize maximumSize = CGSizeMake(300, 9999);NSString *dateString = @"The date today is January 1st, 1999";UIFont *dateFont = [UIFont fontWithName:@"Helvetica" size:14];CGSize dateStringSize = [dateString sizeWithFont:dateFont constrainedToSize:maximumSize lineBreakMode:self.dateLabel.lineBreakMode];CGRect dateFrame = CGRectMake(10, 10, 300, dateStringSize.height);self.dateLabel.frame = dateFrame;

1. Fit the fresh matter:

   myLabel.text = @"Some Text"

2. Fit the maximum number of traces to Zero (computerized):

   myLabel.numberOfLines = 0

3. Fit the framework of the description to the most measurement:

   myLabel.frame = CGRectMake(20,20,200,800)

4. Call sizeToFit to trim the framework measurement truthful the contents conscionable acceptable:

   [myLabel sizeToFit]

The labels framework is present conscionable advanced and broad adequate to acceptable your matter. The apical near ought to beryllium unchanged. I person examined this lone with the apical near-aligned matter. For another alignments, you mightiness person to modify the framework afterward.

Besides, my description has statement wrapping enabled.

Attaining exact matter alignment inside a UILabel successful iOS tin generally beryllium trickier than it seems. Piece horizontal alignment is simple, vertically aligning contented to the apical of a UILabel frequently requires a spot much attempt. This article delves into the nuances of vertically aligning matter to the apical (apical) assumption wrong a UILabel, offering a blanket usher with codification examples and explanations to guarantee your matter seems precisely wherever you mean it to. This is important for creating visually interesting and person-affable interfaces, particularly once dealing with dynamic contented oregon circumstantial plan necessities.

Knowing Vertical Alignment Challenges successful UILabel

The default behaviour of UILabel tends to halfway matter vertically, which mightiness not ever beryllium the desired result. Once dealing with labels that person much abstraction than the matter requires, this centering tin permission undesirable gaps. To efficaciously vertically align matter to the apical, we demand to override this default behaviour. This includes both subclassing UILabel oregon utilizing classes to adhd fresh performance. The prime relies upon connected your task's structure and coding preferences. Knowing these challenges is the archetypal measure in the direction of attaining pixel-clean alignment successful your iOS purposes.

Strategies for Apical Vertical Alignment successful UILabel

Location are respective methods to accomplish the desired apical vertical alignment. 1 communal attack is to subclass UILabel and override the drawText(successful:) methodology to set the drafting rectangle. Different methodology includes utilizing a class to widen UILabel’s performance with out modifying the first people. Some strategies person their benefits and disadvantages, and the champion prime volition be connected the specifics of your task and coding kind. Careless of the attack, the end is to guarantee the matter begins rendering from the apical border of the description's framework.

Present's a examination of the 2 strategies:

Methodology	Benefits	Disadvantages
Subclassing UILabel	Cleanable encapsulation, appropriate for customized description behaviour.	Requires creating a fresh people for all description with apical alignment.
UILabel Class	Extends current UILabel performance, reusable crossed the task.	Tin brand debugging tougher, possible naming conflicts.

Fto's research however to instrumentality all methodology.

Implementing Apical Alignment Done Subclassing

Subclassing UILabel supplies a cleanable, encapsulated manner to customise the drafting behaviour. By creating a fresh people that inherits from UILabel, you tin override the drawText(successful:) methodology to modify however the matter is rendered. This attack is peculiarly utile once you demand to use apical alignment to aggregate labels inside your exertion, arsenic it permits you to reuse the customized description people. The cardinal is to set the rectangle utilized for drafting the matter, making certain it begins astatine the apical of the description's bounds.

Present’s a measure-by-measure usher:

1. Make a fresh Swift record named TopAlignedLabel.swift.
2. Specify a fresh people TopAlignedLabel that subclasses UILabel.
3. Override the drawText(successful:) methodology to set the matter drafting rectangle.
4. Usage this fresh people successful your Storyboard oregon programmatically.

Present’s the codification:

  import UIKit class TopAlignedLabel: UILabel { override func drawText(in rect: CGRect) { guard let text = self.text else { super.drawText(in: rect) return } let stringSize = text.boundingRect( with: CGSize(width: self.frame.width, height: CGFloat.greatestFiniteMagnitude), options: .usesLineFragmentOrigin, attributes: [NSAttributedString.Key.font: self.font ?? UIFont.systemFont(ofSize: 17)], context: nil ) var actualRect = rect actualRect.size.height = stringSize.height super.drawText(in: actualRect) } }  

This codification calculates the required tallness for the matter and adjusts the drafting rectangle accordingly, making certain the matter begins from the apical. Retrieve to fit the description's numberOfLines place to Zero if you privation the matter to wrapper.

If you are having points with away monitoring branches Region monitoring branches nary longer related away, delight cheque the weblog station!

Attaining Apical Alignment Utilizing a Class

An alternate attack is to usage a class to widen the performance of the UILabel people. This permits you to adhd the apical alignment behaviour to immoderate UILabel case successful your task with out creating a fresh people. This is particularly utile if you lone demand apical alignment successful a fewer locations oregon if you like not to make subclasses. The implementation is akin to the subclassing methodology, however alternatively of overriding the drawText(successful:) methodology successful a subclass, you adhd a fresh methodology to the UILabel people itself.

Present’s however to bash it:

1. Make a fresh Swift record named UILabel+VerticalAlignment.swift.
2. Specify a class connected UILabel (an delay successful Swift).
3. Adhd a methodology that calls drawText(successful:) with the adjusted rectangle.
4. Call this methodology successful your codification wherever you demand apical alignment.

Present’s the codification:

  import UIKit extension UILabel { func drawTextAlignedTop() { guard let text = self.text else { return } let stringSize = text.boundingRect( with: CGSize(width: self.frame.width, height: CGFloat.greatestFiniteMagnitude), options: .usesLineFragmentOrigin, attributes: [NSAttributedString.Key.font: self.font ?? UIFont.systemFont(ofSize: 17)], context: nil ) var actualRect = self.bounds actualRect.size.height = stringSize.height super.drawText(in: actualRect) } }  

To usage this class, you would call description.drawTextAlignedTop() alternatively of letting the description gully its matter usually. This methodology adjusts the drafting rectangle to guarantee the matter begins astatine the apical. Support successful head that you whitethorn demand to set off a redraw of the description last mounting its matter to seat the adjustments.

For much connected precocious matter rendering successful iOS, cheque retired Pome's UILabel documentation.

These examples exemplify however to vertically align matter to the apical wrong a UILabel. By subclassing oregon utilizing classes, builders person versatile choices to modify the drafting behaviour of labels and better the general aesthetic and performance of their apps. See these approaches successful your adjacent iOS task, and awareness escaped to experimentation with the codification to accommodate it to your circumstantial wants. By knowing the nuances of matter alignment, you tin trade much visually interesting and person-affable interfaces. Retrieve to trial your implementation connected antithetic gadgets and surface sizes to guarantee accordant outcomes.

Making certain matter successful your app is aligned appropriately enhances the person education. Research much astir UI plan and champion practices astatine Nielsen Norman Radical. Besides, you tin discovery blanket guides and tutorials connected iOS improvement astatine Ray Wenderlich.