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#import "ViewController.h"

@implementation ViewController

- (void)viewDidLoad {

[super viewDidLoad];

// 1.

UILabel *label = [[UILabel alloc] init];

// 1.1 text

// 1.2 font

/**

const CGFloat UIFontWeightUltraLight;

const CGFloat UIFontWeightThin;

const CGFloat UIFontWeightLight;

const CGFloat UIFontWeightRegular;

const CGFloat UIFontWeightMedium;

const CGFloat UIFontWeightSemibold;

const CGFloat UIFontWeightBold;

const CGFloat UIFontWeightHeavy;

const CGFloat UIFontWeightBlack;

+ (UIFont *)systemFontOfSize:(CGFloat)fontSize;

+ (UIFont *)boldSystemFontOfSize:(CGFloat)fontSize; -- 粗体

+ (UIFont *)italicSystemFontOfSize:(CGFloat)fontSize; -- 斜体

+ (UIFont *)systemFontOfSize:(CGFloat)fontSize weight:(CGFloat)weight NS_AVAILABLE_IOS(8_2);

label.font = [UIFont systemFontOfSize:20 weight:UIFontWeightBlack];

// 1.3 textColor

label.textColor = [UIColor magentaColor];

// 1.4 shadowColor

label.shadowColor = [UIColor greenColor];

// 1.5 shadowOffset

label.shadowOffset = CGSizeMake(2, 2);

// 1.6 textAlignment

/**

NSTextAlignmentLeft = 0, // Visually left aligned

NSTextAlignmentCenter = 1, // Visually centered

NSTextAlignmentRight = 2, // Visually right aligned

NSTextAlignmentJustified = 3, // Fully-justified. The last line in a paragraph is natural-aligned.

NSTextAlignmentNatural = 4, // Indicates the default alignment for script

label.textAlignment = NSTextAlignmentLeft;

// 1.7 lineBreakMode

/** --- 设置换行格式

* with long lines

NSLineBreakByWordWrapping = 0, --- 以单词为单位, 自动换行, 显示不全, 没有省略号

NSLineBreakByCharWrapping --- 以字符为单位自动换行, 没有省略号

NSLineBreakByClipping --- 直接切除, 可能显示半个字符

NSLineBreakByTruncatingHead --- 在行头部, 显示省略号

NSLineBreakByTruncatingTail --- 在行尾部, 显示省略号

NSLineBreakByTruncatingMiddle --- 在行中间, 显示省略号

label.lineBreakMode = NSLineBreakByTruncatingTail;

// 1.8 highlighted

// 1.8.1 highlightedTextColor

label.highlighted = NO;

label.highlightedTextColor = [UIColor blackColor];

// 1.9 enabled

// 1.9.1 userInteractionEnabled

label.enabled = YES;

label.userInteractionEnabled = YES;

// 1.10 numberOfLines

label.numberOfLines = 0;

// 1.11 adjustsFontSizeToFitWidth

label.adjustsFontSizeToFitWidth = YES;

// 1.11.1 adjustsLetterSpacingToFitWidth -- 已过期, 用NSKernAttributeName替换

// 1.11.2 minimumFontSize --- -- 已过期, 用minimumScaleFactor替代

label.minimumScaleFactor = .8;

// 1.11.3 baselineAdjustment

/**

UIBaselineAdjustmentAlignBaselines = 0, // default.

UIBaselineAdjustmentAlignCenters,

UIBaselineAdjustmentNone,

label.baselineAdjustment = UIBaselineAdjustmentNone;

// 1.12 -- 绘图中可能会用到

/**

- (CGRect)textRectForBounds:(CGRect)bounds limitedToNumberOfLines:(NSInteger)numberOfLines;

- (void)drawTextInRect:(CGRect)rect;

@property(nonatomic) CGFloat preferredMaxLayoutWidth NS_AVAILABLE_IOS(6_0);

// 1.13 attributedText

NSDictionary *attrs = @{NSForegroundColorAttributeName : [UIColor redColor]};

NSAttributedString *attrString = [[NSAttributedString alloc] initWithString:label.text attributes:attrs];

label.attributedText = attrString;

CGSize size = [UIScreen mainScreen].bounds.size;

label.frame = CGRectMake(10, 100, size.width - 20, 50);

label.backgroundColor = [UIColor lightGrayColor];

[self.view addSubview:label];

}