无法实现UIView子类

Question

我正在尝试创建一个UIView，它基本上是一个带有圆形背景的数字。我正在使用UIView并应用圆的一半尺寸的圆角。然后我将这个数字作为UILabel子视图添加到上面的视图中。

我想要的是接近这个（没有花哨的边框）： （这是应用Count Battle的截图）。

请通过在正确的方法（drawrect，init，layoutSubviews或任何自定义方法）下移动代码来帮助我重写。这是当前形式的代码。我认为我对这件事的理解是混乱的，这看起来不对。

这是头文件：

//  CircleNumView.h

#import <UIKit/UIKit.h>

@interface CircleNumView : UIView

@property (nonatomic, strong) UIColor *circleColor;

- (instancetype)initWithRadius:(CGFloat)radius
                        center:(CGPoint)center
                          text:(NSString *)text;

@end

这是实施文件：

//  CircleNumView.m

#import "CircleNumView.h"

@interface CircleNumView ()

@property (nonatomic) CGFloat radius;
@property (nonatomic, strong) NSString *text;

@end


@implementation CircleNumView

// designated initializer
- (instancetype)initWithRadius:(CGFloat)radius
                        center:(CGPoint)center
                          text:(NSString *)text
{
    self = [super init];

    self.radius = radius;
    self.text = text;
    self.frame = CGRectMake ( center.x - radius, center.y - radius, 2 * radius, 2 * radius);

    self.circleColor = [UIColor whiteColor];

    self = [self createView];

    return self;
}


- (CircleNumView *)createView
{
    CircleNumView *circularView = [[UIView alloc] initWithFrame:self.frame];

    circularView.backgroundColor = self.circleColor;

    UILabel *label = [[UILabel alloc] initWithFrame:circularView.bounds];
    label.text = self.text;
    label.textColor = [UIColor blackColor];

    [circularView addSubview:label];

    circularView.clipsToBounds = YES;
    circularView.layer.cornerRadius = self.radius;

    [self addSubview:circularView];

    return circularView;
}

@end

Answer 1

在self = [createView];

之前，你做得很好

这是我要写的实现文件：

//
//  CircleNumberView.m
//  
//
//  Created by James Valaitis on 13/04/2014.
//
//

#import "CircleNumberView.h"

#pragma mark - Circle Number View Private Class Extension

@interface CircleNumberView ()

/** The radius of this circular view.   */
@property (nonatomic, assign)       CGFloat             radius;
/** The number to present encapsulated as a string. */
@property (nonatomic, copy)         NSString            *text;
/** The label that shows the number contents of this view.  */
@property (nonatomic, strong)       UILabel             *textLabel;

@end

#pragma mark - Circle Number View Implementation

@implementation CircleNumberView

#pragma mark - Initialisation

/**
 *  Initialises a circlular view with a number in the middle.
 *
 *  @param  radius                  The radius of the circle.
 *  @param  center                  The center point of the circle in it's superview.
 *  @param  text                    The number as a string to present in the middle of this view.
 *
 *  @return An initialized object.
 */
- (instancetype)initWithRadius:(CGFloat)radius center:(CGFloat)center text:(NSString *)text
{
    CGRect frame = CGRectMake(center.x - radius, center.y - radius, radius * 2, radius * 2);

    if (self = [super initWithFrame:frame])
    {
        _radius = radius;
        _text = text;

        [self configureViewAndSubviews];
    }

    return self;
}

#pragma mark - Property Accessor Methods - Getters

/**
 *  The label that shows the number contents of this view.
 *
 *  @return The label that shows the number contents of this view.
 */
- (UILabel *)textLabel
{
    if (!_textLabel)
    {
        _textLabel = [[UILabel alloc] initWithFrame:self.bounds];
        _textLabel.numberOfLines = 0;
        _textLabel.textColor = [UIColor blackColor];
    }

    return _textLabel;
}

#pragma mark - Subview Management

/**
 *  Configures this view as well as it's subviews.
 */
- (void)configureViewAndSubviews
{
    self.backgroundColor = [UIColor whiteColor];
    self.clipsToBounds = YES;
    self.layer.cornerRadius = self.radius;

    self.textLabel.text = self.text;
    [self addSubview:self.textLabel];
}

@end