ios开发零散知识点总结

1：当有导航栏的时候，子视图为UIScrollView，或是继承于UIScrollView的控件如UITableView，UICollectionView等，控制器会自动调用

self.automaticallyAdjustsScrollViewInsets = YES；方法，自动为控件添加64的额外的滚动区域，若存在多个控件，则系统会自动找到第一个添加的控件，执行此方法，增加64额外的滚动区域，如果想禁止此操作，可在控制器中实现方法：self.automaticallyAdjustsScrollViewInsets = NO；或是设置UIScrollView的contentInset，tableView的contentInset，来减少滚动区域。

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    // 1：不会自动去调整uiscrollView的contentInset属性
    self.automaticallyAdjustsScrollViewInsets = NO;
    UIScrollView *scrollView = [[UIScrollView alloc] init];
    scrollView.frame = CGRectMake(, , , );
    scrollView.backgroundColor = [UIColor redColor];
    [self.view addSubview:scrollView];

    [scrollView addSubview:[[UISwitch alloc] init]];
}

2：在宏定义文件中的NSLog定义

#ifdef DEBUG

#define DLog(...)  NSLog(__VA_ARGS__)

#else

#define DLog(...)

#endif

一些颜色的宏定义

//1:RGB颜色
#define RGB(a,b,c) [UIColor colorWithRed:(a)/255.0 green:(b)/255.0 blue:(c)/255.0 alpha:1]

//2:包含设置透明度
#define RGBColor(a,b,c,d) [UIColor colorWithRed:(a)/255.0 green:(b)/255.0 blue:(c)/255.0 alpha:d]

//3：随机色
#define ARC4Color RGB(arc4random_uniform(256),arc4random_uniform(256),arc4random_uniform(256))

3：pch文件的定义：在项目的Target---BuildSetting---prefixHeader---删除在桌面文件夹的路径，只保留项目的路径，再输入$(SRCROOT),如：$(SRCROOT)/网易新闻抽屉效果/Classes/Main/Utils/PrefixHeader.pch

4：通过图形上下文将color绘制成一张图片：

 //提供颜色接口，返回一张图片

 #import <UIKit/UIKit.h>

 @interface UIImage (Cqb)

 +(UIImage*)imageWithColor:(UIColor*)color;
 @end

 #import "UIImage+Cqb.h"

 @implementation UIImage (Cqb)

 + (UIImage*)imageWithColor:(UIColor*)color {

     //1:开启基于位图的图形上下文
     CGFloat imageWidth = ;
     CGFloat imageHeight = ;
     UIGraphicsBeginImageContextWithOptions(CGSizeMake(imageWidth, imageHeight), NO, 0.0);

     //2:画一个color颜色的矩形框
     [color set];
     UIRectFill(CGRectMake(, , imageWidth, imageHeight));

     //3:得到图片
     UIImage *image = UIGraphicsGetImageFromCurrentImageContext();

     //4:关闭图形上下文
     UIGraphicsEndImageContext();

     return image;
 }

5：UIView计算尺寸的分类：

 #import <UIKit/UIKit.h>

 @interface UIView (Cqb)
 @property (nonatomic,assign)CGFloat X;
 @property (nonatomic,assign)CGFloat Y;
 @property (nonatomic,assign)CGFloat width;
 @property (nonatomic,assign)CGFloat height;
 @property (nonatomic,assign)CGFloat centerX;
 @property (nonatomic,assign)CGFloat centerY;
 @property (nonatomic,assign)CGSize  size;
 @end

 #import "UIView+Cqb.h"

 @implementation UIView (Cqb)

 - (void)setX:(CGFloat)X {

     CGRect frame = self.frame;
     frame.origin.x = X;
     self.frame = frame;

 }

 - (CGFloat)X {

     return self.frame.origin.x;
 }

 - (void)setY:(CGFloat)Y {

     CGRect frame = self.frame;
     frame.origin.y = Y;
     self.frame = frame;

 }

 - (CGFloat)Y {

     return self.frame.origin.y;
 }

 - (void)setWidth:(CGFloat)width {

     CGRect frame = self.frame;
     frame.size.width = width;
     self.frame = frame;

 }

 - (CGFloat)width {

     return self.frame.size.width;
 }

 - (void)setHeight:(CGFloat)height {

     CGRect frame = self.frame;
     frame.size.height = height;
     self.frame = frame;
 }

 - (CGFloat)height {

     return self.frame.size.height;
 }

 - (void)setCenterX:(CGFloat)centerX {

     CGPoint center = self.center;
     center.x = centerX;
     self.center = center;

 }

 - (CGFloat)centerX {

     return self.center.x;
 }

 - (void)setCenterY:(CGFloat)centerY {

     CGPoint center = self.center;
     center.y = centerY;
     self.center = center;
 }

 - (CGFloat)centerY {

     return self.center.y;
 }

 - (void)setSize:(CGSize)size {

     CGRect frame = self.frame;
     frame.size = size;
     self.frame = frame;

 }

 - (CGSize)size {

     return self.frame.size;
 }

 @end

6：对自定义UIBarButtonItem的分类封装：

 #import <UIKit/UIKit.h>

 @interface UIBarButtonItem (Extension)
 + (UIBarButtonItem *)itemWithImageName:(NSString *)imageName target:(id)target action:(SEL)action;
 @end

 #import "UIBarButtonItem+Extension.h"

 @implementation UIBarButtonItem (Extension)
 + (UIBarButtonItem *)itemWithImageName:(NSString *)imageName target:(id)target action:(SEL)action
 {
     UIButton *button = [[UIButton alloc] init];
     [button setBackgroundImage:[UIImage imageNamed:imageName] forState:UIControlStateNormal];

     // 设置按钮的尺寸为背景图片的尺寸
     button.size = button.currentBackgroundImage.size;

     // 监听按钮点击
     [button addTarget:target action:action forControlEvents:UIControlEventTouchUpInside];
     return [[UIBarButtonItem alloc] initWithCustomView:button];
 }
 @end

6：当做真机调试的时候，要在buildSetting中配置好证书，并在info里选择开发者账号才可以