ios基础篇（二十四）—— 文字、图片的绘制及其自定义Button

这篇文章我们主要来拿官方的控件来研究一下，我们来仿照官方的控件，自己来实现它提供的控件；

首先来看看基本的图片与文字的绘制，很简单。

一、imageView

所有的视图都是继承自UIView，所以我们的ImageView也是继承自UIView，我们自己写的用My开头，以便于区分。

1、对于ImageView，我们需要绘制，需要提供图片资源，所以在我们的头文件里我们这样定义:

2、回到MyImageView.m文件里，找到绘制函数：

嗯，没错这样就写完了。。。

接下来回到ViewController.m里试试我们自己写的控件吧！

3、在ViewController.m中引入我们刚才自定义的View，

 @interface ViewController (){

     MyImageView *imageView;

 }

 @end

 @implementation ViewController

 - (void)viewDidLoad {
     [super viewDidLoad];
     // Do any additional setup after loading the view, typically from a nib.
     imageView = [[MyImageView alloc] initWithFrame:(CGRect){,,,}];
     imageView.image = [UIImage imageNamed:@"u=1940733206,3299197276&fm=21&gp=0"];
     [self.view addSubview:imageView];

 }

看看效果：

还不错吧，是不是和苹果官方提供的控件一样好用。。

二、Label

Label的绘制会稍微复杂一点，

首先还是创建我们自己的View（MyLabel）。

1、打开MyLabel.h文件，

设置我们在UILabel控件中常用的属性，这里只写几个举例说明一下，具体用到时候根据需要设置。

2、回到MyLabel.m文件，

 #import "MyLabel.h"

 @implementation MyLabel

 // Only override drawRect: if you perform custom drawing.
 // An empty implementation adversely affects performance during animation.
 - (void)drawRect:(CGRect)rect {
     // Drawing code

     NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
     paragraphStyle.lineBreakMode = NSLineBreakByCharWrapping;
     paragraphStyle.alignment = NSTextAlignmentLeft;

     NSDictionary *dic = @{NSParagraphStyleAttributeName:paragraphStyle,
                           NSForegroundColorAttributeName:_textColor,//设置字体颜色
                           NSBackgroundColorAttributeName:_backgroundColor,//设置背景色
                           NSFontAttributeName:_font,//设置字体
                           NSStrokeWidthAttributeName:@,//设置描边宽度，这样就能使文字空心
                           NSStrokeColorAttributeName:[UIColor greenColor],//设置文字描边颜色
                           };
     [_text drawInRect:(CGRect){,,,} withAttributes:dic];

 }

3、回到ViewController.m文件，

引入MyLabel.h文件，

 @interface ViewController (){

     MyImageView *imageView;
     MyLabel *label;
 }

 @end

 @implementation ViewController

 - (void)viewDidLoad {
     [super viewDidLoad];
     // Do any additional setup after loading the view, typically from a nib.
     imageView = [[MyImageView alloc] initWithFrame:(CGRect){,,,}];
     imageView.image = [UIImage imageNamed:@"u=1940733206,3299197276&fm=21&gp=0"];
     [self.view addSubview:imageView];

     label = [[MyLabel alloc] initWithFrame:(CGRect){,,,}];
     label.text = @"Hello,World!";
     label.backgroundColor = [UIColor whiteColor];
     label.textColor = [UIColor orangeColor];
     label.font = [UIFont systemFontOfSize:];
     [self.view addSubview:label];
 }

效果图：

三、自定义Button

首先新建View（MyButton），继承自UIView，为什么不直接继承自UIControl？因为我们要自己添加手势！

1、打开MyButton.h文件,添加方法

 #import <UIKit/UIKit.h>

 @interface MyButton : UIView

 - (void)addTarget:(id)target action:(SEL)action forControlEvents:(UIControlEvents)controlEvents;//添加手势
 - (void)setImage:(UIImage*)image forState:(UIControlState)state;//设置button图片
 - (void)setTitle:(NSString*)title forState:(UIControlState)state;//设置文字

 @end

2、打开MyButton.m文件，

声明自定义属性，及其初始化方法，

 //
 //  MyButton.m
 //  Draw
 //
 //  Created by Oran Wu on 15-12-30.
 //  Copyright (c) 2015年 Xinxin. All rights reserved.
 //

 #import "MyButton.h"

 @interface MyButton (){

     UIControlEvents controlEvent;

     UIImage *_buttonImage;
     UIControlState controlState;

     NSString *_buttonTitle;

     UIBezierPath *buttonPath;
 }
 @property(nonatomic,weak)id targate;
 @property(nonatomic,assign)SEL buttonAction;

 @end

 @implementation MyButton

 - (id)initWithFrame:(CGRect)frame{
     self = [super initWithFrame:frame];
     if (self) {
         self.backgroundColor = [UIColor whiteColor];
     }
     return self;
 }

 - (void)addTarget:(id)target action:(SEL)action forControlEvents:(UIControlEvents)controlEvents{

     self.targate = target;
     self.buttonAction = action;
     controlEvent = controlEvents;

 }

 - (void)setImage:(UIImage *)image forState:(UIControlState)state{
     _buttonImage = image;
     controlState = state;
     [self setNeedsDisplay];
 }

 - (void)setTitle:(NSString *)title forState:(UIControlState)state{
     _buttonTitle = title;
     controlState = state;
     [self setNeedsDisplay];
 }

3、绘制Button，添加点击事件；

 - (void)drawRect:(CGRect)rect {
     // Drawing code
     UIColor *color = [UIColor colorWithRed:0.3 green:0.7 blue:0.6 alpha:0.5];
     [color set];

     buttonPath = [UIBezierPath bezierPathWithRoundedRect:(CGRect){,,,} cornerRadius:];
     buttonPath.lineWidth = ;
     [buttonPath fill];

     //设置图片
     [_buttonImage drawInRect:(CGRect){,,,}];

     //设置文字
     NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
     paragraphStyle.lineBreakMode = NSLineBreakByCharWrapping;
     paragraphStyle.alignment = NSTextAlignmentCenter;

     NSDictionary *dic = @{NSParagraphStyleAttributeName:paragraphStyle,
                           NSForegroundColorAttributeName:[UIColor redColor],//设置字体颜色
                           NSBackgroundColorAttributeName:[UIColor clearColor],//设置背景色
                           NSFontAttributeName:[UIFont systemFontOfSize:],//设置字体
                           NSStrokeWidthAttributeName:@,//设置描边宽度，这样就能使文字空心
                           NSStrokeColorAttributeName:[UIColor purpleColor],//设置文字描边颜色
                           };
     [_buttonTitle drawInRect:(CGRect){,,,} withAttributes:dic];

 }

 //开始触摸
 - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
     //按需求设置点击状态
 }

 //结束触摸
 - (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{

     if (controlEvent==UIControlEventTouchUpInside) {

         [self.targate performSelector:self.buttonAction withObject:self];

     }

 }

4、返回ViewController.m文件试试我们自定义的Button；

同样，引入头文件，

在- (void)viewDidLoad;方法中写入以下代码（这里设置了Button的背景颜色，就没有设置图片，如果有需要把文字加在图片上面也是可以的）；

     button = [[MyButton alloc] initWithFrame:(CGRect){,,,}];
     [button setTitle:@"myButton" forState:UIControlStateNormal];
     //[button setImage:[UIImage imageNamed:@"u=38807319,2604887842&fm=15&gp=0"] forState:UIControlStateNormal];
     [self.view addSubview:button];
     [button addTarget:self action:@selector(buttonAction) forControlEvents:UIControlEventTouchUpInside];

效果图：

Button点击动作响应：

 - (void)buttonAction{
     //设置改变文字
     [button setTitle:@"Change" forState:UIControlStateNormal];

 }

效果图：