IOS--UILabel的使用方法詳細

IOS-UILabel的使用方法詳細

 

   //UILabel的使用

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

    // 最常常使用的

   oneLabel.frame = CGRectMake(0, 0, 320, 200); // 設置oneLabel的位置和大小

   oneLabel.text = @"我是一個UILabel哦，"; // 設置oneLabel顯示的字

   oneLabel.textColor = [UIColor blackColor]; // 設置字體顏色

   oneLabel.backgroundColor = [UIColor redColor]; // 設置背景色

   oneLabel.backgroundColor = [UIColor clearColor]; // 能夠設置透明背景色

   oneLabel.alpha = 1.0; // 設置透明度 （範圍是0.0-1.0之間）

    

    // 字體和字體大小

   oneLabel.font = [UIFont fontWithName:@"Helvetica" size:25.4f]; // 設置顯示的字的字體和大小，當字體不存在時，大小也是無效的

   oneLabel.font = [UIFont systemFontOfSize:35.0f]; // 只設置字體大小

   oneLabel.font = [UIFont boldSystemFontOfSize:35.0f]; // 設置字體大小併爲粗體

    

     oneLabel.textAlignment = NSTextAlignmentCenter; // 設置字體的顯示位置：左對齊、居中、右對齊

     oneLabel.adjustsFontSizeToFitWidth = YES; // 設置字體大小自動適應高度

     oneLabel.userInteractionEnabled = YES; // 設置是否能夠與用戶進行交互

     oneLabel.enabled = YES; // 設置oneLabel的text是否能夠改變，默認是YES

    

   // 設置行數，前提是高度是足夠的

   // 設置行數爲0，能夠根據文本計算對應文本的高度寬度後，所有顯示徹底，默認單行顯示

   oneLabel.numberOfLines = 3;

    

   // 設置是否能夠高亮

   oneLabel.highlighted = YES;

   oneLabel.highlightedTextColor = [UIColor redColor];

    

    // 設置陰影

   oneLabel.shadowColor = [UIColor grayColor];

   oneLabel.shadowOffset = CGSizeMake(2.0, 2.0);

    

   //設置文字過長時的顯示格式

     oneLabel.lineBreakMode = NSLineBreakByClipping;

//    typedef NS_ENUM(NSInteger, NSLineBreakMode) {

//        NSLineBreakByWordWrapping = 0,    

//        NSLineBreakByCharWrapping,

//        NSLineBreakByClipping,

//        NSLineBreakByTruncatingHead,

//        NSLineBreakByTruncatingTail,

//        NSLineBreakByTruncatingMiddle

//    }

    

     //若是adjustsFontSizeToFitWidth屬性設置爲YES，這個屬性就來控制文本基線的行爲

     oneLabel.baselineAdjustment = UIBaselineAdjustmentAlignBaselines;

    //  typedef enum {

    //      UIBaselineAdjustmentAlignBaselines,

    //      UIBaselineAdjustmentAlignCenters,

    //      UIBaselineAdjustmentNone,

    //  } UIBaselineAdjustment;

    

 

     // 把oneLabel添加到view上面，並釋放內存

    [self.view addSubview:oneLabel];

    [oneLabel release], oneLabel = nil;

    

      // 附：

     // NSLog(@"%@", [UIFont familyNames]); // 能夠打印出所有存在的字體

 

 UILabel 詳解

 

UILabel 多行文字自動換行 （自動折行）

1.UIView *footerView = [[UIView alloc] initWithFrame:CGRectMake(10, 100, 300, 180)];   
2.    UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(10, 100, 300, 150)];   
3.    label.text = @"where are you? where are you? where are you? where are you? where are you? where are you? where are you? where are you? where are you? where are you?";   
4.    //清空背景顏色   
5.    label.backgroundColor = [UIColor clearColor];   
6.    //設置字體顏色爲白色   
7.    label.textColor = [UIColor whiteColor];   
8.    //文字居中顯示   
9.    label.textAlignment = UITextAlignmentCenter;   
10.    //自動折行設置   
11.    label.lineBreakMode = UILineBreakModeWordWrap;   
12.    label.numberOfLines = 0;  

 

iOS的UILabel設置居上對齊，居中對齊，居下對齊

在iOS中默認的UILabel中的文字在豎直方向上只能居中對齊，博主參考國外網站，從UILabel繼承了一個新類，實現了居上對齊，居中對齊，居下對齊。具體以下：

//
//  myUILabel.h
//
//
//  Created by yexiaozi_007 on 3/4/13.
//  Copyright (c) 2013 yexiaozi_007. All rights reserved.
//

#import <UIKit/UIKit.h>
typedef enum
{
    VerticalAlignmentTop = 0, // default
    VerticalAlignmentMiddle,
    VerticalAlignmentBottom,
} VerticalAlignment;
@interface myUILabel : UILabel
{
@private
VerticalAlignment _verticalAlignment;
}

@property (nonatomic) VerticalAlignment verticalAlignment;

@end

 

//
//  myUILabel.m
//
//
//  Created by yexiaozi_007 on 3/4/13.
//  Copyright (c) 2013 yexiaozi_007. All rights reserved.
//

#import "myUILabel.h"

@implementation myUILabel
@synthesize verticalAlignment = verticalAlignment_;

- (id)initWithFrame:(CGRect)frame {
    if (self = [super initWithFrame:frame]) {
        self.verticalAlignment = VerticalAlignmentMiddle;
    }
    return self;
}

- (void)setVerticalAlignment:(VerticalAlignment)verticalAlignment {
    verticalAlignment_ = verticalAlignment;
    [self setNeedsDisplay];
}

- (CGRect)textRectForBounds:(CGRect)bounds limitedToNumberOfLines:(NSInteger)numberOfLines {
    CGRect textRect = [super textRectForBounds:bounds limitedToNumberOfLines:numberOfLines];
    switch (self.verticalAlignment) {
        case VerticalAlignmentTop:
            textRect.origin.y = bounds.origin.y;
            break;
        case VerticalAlignmentBottom:
            textRect.origin.y = bounds.origin.y + bounds.size.height - textRect.size.height;
            break;
        case VerticalAlignmentMiddle:
            // Fall through.
        default:
            textRect.origin.y = bounds.origin.y + (bounds.size.height - textRect.size.height) / 2.0;
    }
    return textRect;
}

-(void)drawTextInRect:(CGRect)requestedRect {
    CGRect actualRect = [self textRectForBounds:requestedRect limitedToNumberOfLines:self.numberOfLines];
    [super drawTextInRect:actualRect];
}


@end

 

在使用時：

 

lbl_mylabel = [[myUILabel alloc] initWithFrame:CGRectMake(20, 50, 150, 600)];
UIColor *color = [UIColor colorWithPatternImage:[UIImage imageNamed:@"halfTransparent.png"]];//使用半透明圖片做爲label的背景色
lbl_mylabel.backgroundColor = color;
lbl_mylabel.textAlignment = UITextAlignmentLeft;
lbl_mylabel.textColor = UIColor.whiteColor;
lbl_mylabel.lineBreakMode = UILineBreakModeWordWrap;
lbl_mylabel.numberOfLines = 0;
[lbl_mylabel setVerticalAlignment:VerticalAlignmentTop];
[self addSubview:lbl_mylabel];