iOS 一些简单但是实用的知识点
1. 点击页面，收回键盘
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITextField *fd1 = (UITextField *)[self.view viewWithTag:100];
[fd1 resignFirstResponder];
//[self.view endEditing:YES];
}
2. label的自适应宽度
_label.adjustsFontSizeToFitWidth = YES;
3.文件单独支持手动内存
-fno-objc-arc
文件单独支持自动内存
-f-objc-arc
4.沙盒路径
NSHomeDirectory()
5.MJ刷新 Xcode6
1. MJRefreshConst.m 里面 会报错: unknown type ‘NSString‘...
原因: xcode6 取消.pch文件, 所以没有导入 foundation和uikit框架
解决方法: 在MJRefreshConst.m头部加上
#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
2.
objc_msgSend(self.beginRefreshingTaget, self.beginRefreshingAction, self);
Too many arguments to function call, expected 0, have 3
经过几番周折，终于叨叨解决方案了
选中项目 - Project - Build Settings - ENABLE_STRICT_OBJC_MSGSEND 将其设置为 NO 即可
6.Xcode6 自己添加PCH文件设置其路径
$(SRCROOT)/MC/Prefix.pch
hei
[UIColor colorWithRed:35.0/255 green:35.0/255 blue:35.0/255 alpha:1];
hui
[UIColor colorWithRed:112.0/255 green:112.0/255 blue:112.0/255 alpha:1];
7.当前屏幕宽
[UIScreen mainScreen].bounds.size.width
8.PCH
#ifdef __OBJC__
#import <UIKit/UIKit.h>
#import <Foundation/Foundation.h>
#endif
在Build Settings中改变Prefix Header的
$(SRCROOT)/Wei/Prefix.pch
9.网址中文重新编码
ASIHTTPRequest *_re = [[ASIHTTPRequest alloc] initWithURL:[NSURL URLWithString:[str stringByAddingPercentEscapesUsingEncoding: NSUTF8StringEncoding]]];
10.设置背景色
float a = arc4random()%256/255.0;
float b = arc4random()%256/255.0;
float c = arc4random()%256/255.0;
self.view.backgroundColor = [UIColor colorWithRed:a green:b blue:c alpha:1];
11.Cell
//设置cell的阴影线为透明
_tableView.separatorStyle = UITableViewCellSeparatorStyleNone;
//cell的选中的背景色
cell.selectionStyle = UITableViewCellSelectionStyleNone;
12.启动图
640*960
640*1136
58*58
87*87
80*80
120*120
120*120
180*180
13.从这张图片汲取颜色，作为背景色
self.view.backgroundColor=[UIColor colorWithPatternImage:[UIImage imageNamed:@"logo_bg_2.png"]];
14.十六进制配颜色
#define UIColorFromRGB(rgbValue) [UIColor colorWithRed:((float)((rgbValue & 0xFF0000) >> 16))/255.0 green:((float)((rgbValue & 0xFF00) >> 8))/255.0 blue:((float)(rgbValue & 0xFF))/255.0 alpha:1.0]
UIColorFromRGB(0xf7f7f7);
#define UIColorFromRGB(rgbValue) [UIColor colorWithRed:((float)((rgbValue & 0xFF0000) >> 16))/255.0 green:((float)((rgbValue & 0xFF00) >> 8))/255.0 blue:((float)(rgbValue & 0xFF))/255.0 alpha:1.0]
NSString *color = [[NSString alloc] initWithString:model.drug_hot_color];
leibiao.backgroundColor = [AOColorFormat colorWithHexString:color];
15.最普通动画:
//开始动画
[UIView beginAnimations:nil context:nil];
//设定动画持续时间
[UIView setAnimationDuration:2];
//动画的内容
frame.origin.x += 150;
[img setFrame:frame];
//动画结束
[UIView commitAnimations];
16.圆角与边框
//给图层添加背景图片：
//myView.layer.contents = (id)[UIImage imageNamed:@"view_BG.png"].CGImage;
//将图层的边框设置为圆
myWebView.layer.cornerRadius = 8;
myWebView.layer.masksToBounds = YES;
//给图层添加一个有色边框
myWebView.layer.borderWidth = 5;
myWebView.layer.borderColor = [[UIColor colorWithRed:0.52 green:0.09 blue:0.07 alpha:1] CGColor];
17.文字高度与宽度
CGSize textSize = [showText sizeWithFont:[UIFont systemFontOfSize:12]];
CGRect rect = [model.drug_hot_name boundingRectWithSize:CGSizeMake(WIDTH, 9999) options:NSStringDrawingUsesLineFragmentOrigin attributes:[NSDictionary dictionaryWithObject:[UIFont systemFontOfSize:font1+2] forKey:NSFontAttributeName] context:nil];
18.数组去重
NSMutableArray *categoryArray = [[NSMutableArray alloc] init];
for (unsigned i = 0; i < [nameArray count]; i++){
if ([categoryArray containsObject:[nameArray objectAtIndex:i]] == NO){
[categoryArray addObject:[nameArray objectAtIndex:i]];
}
}
19.iOS
［1］概念
iOS的版本号，一个叫做Version，一个叫做Build，这两个值都可以在Xcode 中选中target，点击“Summary”后看到。 Version在plist文件中的key是“CFBundleShortVersionString”，和AppStore上的版本号保持一致，Build在plist中的key是“CFBundleVersion”，代表build的版本号，该值每次build之后都应该增加1。这两个值都可以在程序中通过下面的代码获得：
[[[NSBundle mainBundle] infoDictionary] valueForKey:@"key"]
［2］具体实现
代码实现获得应用的Verison号：
[[[NSBundle mainBundle] infoDictionary] objectForKey:@"xxxxxx"]
或
[[NSBundle mainBundle] objectForInfoDictionaryKey:@"xxxxxx"];
获得build号：
[[[NSBundle mainBundle] infoDictionary] objectForKey:@"xxxxxxxx"]
20.设置按钮不能同时被点击
[starBtn3 setExclusiveTouch:YES];
21.UIView基础【动画效果】
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:0.5];
//do something
[UIView commitAnimations];
[UIView animateWithDuration:.2 animations:^{
huang.frame = CGRectMake(WIDTH+20, 0, WIDTH, HEIGHT);
}];
[NSTimer scheduledTimerWithTimeInterval:.2 target:self selector:@selector(time) userInfo:nil repeats:NO];
22.设置rootViewController
AppDelegate * dele = (AppDelegate *)app.delegate;
dele.window.rootViewController = nc;
23.UIImageView 的contentMode属性
UIViewContentModeScaleToFill
UIViewContentModeScaleAspectFit
UIViewContentModeScaleAspectFill
UIViewContentModeRedraw
UIViewContentModeCenter
UIViewContentModeTop
UIViewContentModeBottom
UIViewContentModeLeft
UIViewContentModeRight
UIViewContentModeTopLeft
UIViewContentModeTopRight
UIViewContentModeBottomLeft
UIViewContentModeBottomRight
注意以上几个常量，凡是没有带Scale的，当图片尺寸超过
ImageView尺寸时，只有部分显示在ImageView中。UIViewContentModeScaleToFill属性会导致图片变形。UIViewContentModeScaleAspectFit会保证图片比例不变，而且全部显示在ImageView中，这意味着ImageView会有部分空白。UIViewContentModeScaleAspectFill也会证图片比例不变，但是是填充整个ImageView的，可能只有部分图片显示出来。
24.去掉btn点击事件，加新的点击事件
[pass_button removeTarget:self action:@selector(oneClick) forControlEvents:UIControlEventTouchUpInside];
[pass_button addTarget:self action:@selector(twoClick) forControlEvents:UIControlEventTouchUpInside];
25.求字符串宽高
+(CGRect)stringRectfor:(NSString*)string font:(UIFont*)font width:(CGFloat)width
{
CGRect textgetRect;
if( [[[UIDevice currentDevice] systemVersion] doubleValue]>=7.0)
{
NSDictionary *dict = [NSDictionary dictionaryWithObject:font forKey:NSFontAttributeName];
textgetRect = [string boundingRectWithSize:CGSizeMake(width, MAXFLOAT) options:NSStringDrawingUsesLineFragmentOrigin attributes:dict context:nil];
}
else
{
textgetRect.size = [string sizeWithFont:font constrainedToSize:CGSizeMake(width, MAXFLOAT) lineBreakMode:NSLineBreakByCharWrapping];
}
return textgetRect;
}
26.判断当前navigationController有几层
if ([self.navigationController.viewControllers count] == 1)
{
bottomPadding = 49;
}else{
bottomPadding = 0;
}
