开发知识汇总
关键字const
的位置
const意味着”只读”,分析下面的含义
const int a;
int const a;
// 前两个的作用是一样,a是一个常整型数。
const int *a;
// 第三个意味着a是一个指向常整型数的指针(整型数是不可修改的,但指针可以)
int * const a;
// 第四个意思a是一个指向整型数的常指针(指针指向的整型数是可以修改的,但指针是不可修改的)
int const * const a;
// a是一个指向常整型数的常指针(指针指向的整型数是不可修改的,同时指针也是不可修改的)。表示a是一个指针常量,初始化的时候必须固定指向一个int常量或者int变量,之后就不能再指向别的地方了,它总是把它所指向的目标当作一个int常量。也可以写成const int* const a;含义相同。
滑动隐藏导航栏(navigation bar)
navigationController.hidesBarsOnSwipe = YES;
Navigationbar变成透明而不模糊(navigation bar)
[self.navigationController.navigationBar setBackgroundImage:[UIImage new]
forBarMetrics:UIBarMetricsDefault];
self.navigationController.navigationBar .shadowImage = [UIImage new];
self.navigationController.navigationBar .translucent = YES;
仿系统弹出出动画(渐变大)
必须把changeOutView先添加到父视图上去
+(void)exChangeOut:(UIView *)changeOutView dur:(CFTimeInterval)dur{ CAKeyframeAnimation * animation; animation = [CAKeyframeAnimation animationWithKeyPath:@"transform"];
animation.duration = dur;
animation.delegate = self;
animation.removedOnCompletion = NO;
animation.fillMode = kCAFillModeForwards; NSMutableArray *values = [NSMutableArray array];
[values addObject:[NSValue valueWithCATransform3D:CATransform3DMakeScale(0.1, 0.1, 1.0)]];
[values addObject:[NSValue valueWithCATransform3D:CATransform3DMakeScale(1.2, 1.2, 1.0)]];
[values addObject:[NSValue valueWithCATransform3D:CATransform3DMakeScale(0.9, 0.9, 0.9)]];
[values addObject:[NSValue valueWithCATransform3D:CATransform3DMakeScale(1.0, 1.0, 1.0)]];
animation.values = values; animation.timingFunction = [CAMediaTimingFunction functionWithName: @"easeInEaseOut"];
[changeOutView.layer addAnimation:animation forKey:nil];
}
关于View
view.layer.shouldRasterize = YES;//去除View锯齿
view.layer.shadowColor //投影颜色
view.layer.shadowOffset //投影偏移量
view.layer.shadowRadius //投影弧度
view.layer.shadowPath //投影路径
#设置View 的圆角等样式都是设置 view.layer 的属性
关于导航栏
//设置导航栏颜色(全局设置)
[[UINavigationBar appearance] setBarTintColor:UIColorFromRGB(0x067AB5)];
//设置导航栏背景图片
[[UINavigationBar appearance] setBackgroundImage:[UIImage imageNamed:@"nav_bg.png"] forBarMetrics:UIBarMetricsDefault];
//自定义返回按钮图片(默认状态)
[[UINavigationBar appearance] setBackIndicatorImage:[UIImage imageNamed:@"back_btn.png"]];
//自定义返回按钮图片(按下状态)
[[UINavigationBar appearance] setBackIndicatorTransitionMaskImage:[UIImage imageNamed:@"back_btn.png"]];
#设置导航返回按钮颜色(除了返回按钮,tintColor属性会影响到所有按钮标题和图片。)
[[UINavigationBar appearance] setTintColor:[UIColor whiteColor]];
//修改导航栏的返回按钮颜色
self.navigationController.tintcolor = color
//设置导航栏标题的风格(dictionary key
UITextAttributeFont – 字体key
UITextAttributeTextColor – 文字颜色key
UITextAttributeTextShadowColor – 文字阴影色key
UITextAttributeTextShadowOffset – 文字阴影偏移量key)
UITextAttributeFont 字体大小
[[UINavigationBar appearance] setTitleTextAttributes:(NSDictionary<NSString *,id> * _Nullable)]
//自定义导航栏View (一般用于设置图片,或者按钮)
self.navigationItem.titleView = view
版本号比较
if ([string1 compare:@"string2"] == 0) {
//版本相等
}
禁止键盘弹出时UIWebView自动滑动
webview.scrollView.delegate=self;
-(UIView*)viewForZoomingInScrollView:(UIScrollView*)scrollView {
return nil;
}
有时候layer.cornerRadius并不能满足需求,自己实现drawRect又太麻烦,怎么办?
- (void)dwMakeBottomRoundCornerWithRadius:(CGFloat)radius view:(UIView *)views
{
CGSize size = views.frame.size;
CAShapeLayer *shapeLayer = [CAShapeLayer layer];
[shapeLayer setFillColor:[[UIColor whiteColor] CGColor]];
CGMutablePathRef path = CGPathCreateMutable();
CGPathMoveToPoint(path, NULL, size.width - radius, size.height);
CGPathAddArc(path, NULL, size.width-radius, size.height-radius, radius, M_PI/2, 0.0, YES);
CGPathAddLineToPoint(path, NULL, size.width, 0.0);
CGPathAddLineToPoint(path, NULL, 0.0, 0.0);
CGPathAddLineToPoint(path, NULL, 0.0, size.height - radius);
CGPathAddArc(path, NULL, radius, size.height - radius, radius, M_PI, M_PI/2, YES);
CGPathCloseSubpath(path);
[shapeLayer setPath:path];
CFRelease(path);
views.layer.mask = shapeLayer;//layer的mask,顾名思义,是种位掩蔽,在shapeLayer的填充区域中,alpha值不为零的部分,self会被绘制;alpha值为零的部分,self不会被绘制,甚至不会响应touch
}
drawrect 画线
- (void)drawRect:(CGRect)rect
{
CGContextRef context = UIGraphicsGetCurrentContext();
/*NO.1画一条线
CGContextSetRGBStrokeColor(context, 0.5, 0.5, 0.5, 0.5);//线条颜色
CGContextMoveToPoint(context, 20, 20);
CGContextAddLineToPoint(context, 200,20);
CGContextStrokePath(context);
*/
/*NO.2写文字
CGContextSetLineWidth(context, 1.0);
CGContextSetRGBFillColor (context, 0.5, 0.5, 0.5, 0.5);
UIFont *font = [UIFont boldSystemFontOfSize:18.0];
[@"公司:北京中软科技股份有限公司\n部门:ERP事业部\n姓名:McLiang" drawInRect:CGRectMake(20, 40, 280, 300) withFont:font];
*/
/*NO.3画一个正方形图形 没有边框
CGContextSetRGBFillColor(context, 0, 0.25, 0, 0.5);
CGContextFillRect(context, CGRectMake(2, 2, 270, 270));
CGContextStrokePath(context);
*/
/*NO.4画正方形边框
CGContextSetRGBStrokeColor(context, 0.5, 0.5, 0.5, 0.5);//线条颜色
CGContextSetLineWidth(context, 2.0);
CGContextAddRect(context, CGRectMake(2, 2, 270, 270));
CGContextStrokePath(context);
*/
/*NO.5画方形背景颜色
CGContextTranslateCTM(context, 0.0f, self.bounds.size.height);
CGContextScaleCTM(context, 1.0f, -1.0f);
UIGraphicsPushContext(context);
CGContextSetLineWidth(context,320);
CGContextSetRGBStrokeColor(context, 250.0/255, 250.0/255, 210.0/255, 1.0);
CGContextStrokeRect(context, CGRectMake(0, 0, 320, 460));
UIGraphicsPopContext();
*/
/*NO.6椭圆
CGRect aRect= CGRectMake(80, 80, 160, 100);
CGContextSetRGBStrokeColor(context, 0.6, 0.9, 0, 1.0);
CGContextSetLineWidth(context, 3.0);
CGContextAddEllipseInRect(context, aRect); //椭圆
CGContextDrawPath(context, kCGPathStroke);
*/
/*NO.7
CGContextBeginPath(context);
CGContextSetRGBStrokeColor(context, 0, 0, 1, 1);
CGContextMoveToPoint(context, 100, 100);
CGContextAddArcToPoint(context, 50, 100, 50, 150, 50);
CGContextStrokePath(context);
*/
/*NO.8渐变
CGContextClip(context);
CGColorSpaceRef rgb = CGColorSpaceCreateDeviceRGB();
CGFloat colors[] =
{
204.0 / 255.0, 224.0 / 255.0, 244.0 / 255.0, 1.00,
29.0 / 255.0, 156.0 / 255.0, 215.0 / 255.0, 1.00,
0.0 / 255.0, 50.0 / 255.0, 126.0 / 255.0, 1.00,
};
CGGradientRef gradient = CGGradientCreateWithColorComponents
(rgb, colors, NULL, sizeof(colors)/(sizeof(colors[0])*4));
CGColorSpaceRelease(rgb);
CGContextDrawLinearGradient(context, gradient,CGPointMake
(0.0,0.0) ,CGPointMake(0.0,self.frame.size.height),
kCGGradientDrawsBeforeStartLocation);
*/
/* NO.9四条线画一个正方形
//画线
UIColor *aColor = [UIColor colorWithRed:0 green:1.0 blue:0 alpha:0];
CGContextSetRGBStrokeColor(context, 1.0, 0, 0, 1.0);
CGContextSetFillColorWithColor(context, aColor.CGColor);
CGContextSetLineWidth(context, 4.0);
CGPoint aPoints[5];
aPoints[0] =CGPointMake(60, 60);
aPoints[1] =CGPointMake(260, 60);
aPoints[2] =CGPointMake(260, 300);
aPoints[3] =CGPointMake(60, 300);
aPoints[4] =CGPointMake(60, 60);
CGContextAddLines(context, aPoints, 5);
CGContextDrawPath(context, kCGPathStroke); //开始画线
*/
/* NO.10
UIColor *aColor = [UIColor colorWithRed:0 green:1.0 blue:0 alpha:0];
CGContextSetRGBStrokeColor(context, 1.0, 0, 0, 1.0);
CGContextSetFillColorWithColor(context, aColor.CGColor);
//椭圆
CGRect aRect= CGRectMake(80, 80, 160, 100);
CGContextSetRGBStrokeColor(context, 0.6, 0.9, 0, 1.0);
CGContextSetLineWidth(context, 3.0);
CGContextSetFillColorWithColor(context, aColor.CGColor);
CGContextAddRect(context, rect); //矩形
CGContextAddEllipseInRect(context, aRect); //椭圆
CGContextDrawPath(context, kCGPathStroke);
*/
/* NO.11
画一个实心的圆
CGContextFillEllipseInRect(context, CGRectMake(95, 95, 100.0, 100));
*/
/*NO.12
画一个菱形
CGContextSetLineWidth(context, 2.0);
CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
CGContextMoveToPoint(context, 100, 100);
CGContextAddLineToPoint(context, 150, 150);
CGContextAddLineToPoint(context, 100, 200);
CGContextAddLineToPoint(context, 50, 150);
CGContextAddLineToPoint(context, 100, 100);
CGContextStrokePath(context);
*/
/*NO.13 画矩形
CGContextSetLineWidth(context, 2.0);
CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
CGRect rectangle = CGRectMake(60,170,200,80);
CGContextAddRect(context, rectangle);
CGContextStrokePath(context);
*/
/*椭圆
CGContextSetLineWidth(context, 2.0);
CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
CGRect rectangle = CGRectMake(60,170,200,80);
CGContextAddEllipseInRect(context, rectangle);
CGContextStrokePath(context);
*/
/*用红色填充了一段路径:
CGContextMoveToPoint(context, 100, 100);
CGContextAddLineToPoint(context, 150, 150);
CGContextAddLineToPoint(context, 100, 200);
CGContextAddLineToPoint(context, 50, 150);
CGContextAddLineToPoint(context, 100, 100);
CGContextSetFillColorWithColor(context, [UIColor redColor].CGColor);
CGContextFillPath(context);
*/
/*填充一个蓝色边的红色矩形
CGContextSetLineWidth(context, 2.0);
CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
CGRect rectangle = CGRectMake(60,170,200,80);
CGContextAddRect(context, rectangle);
CGContextStrokePath(context);
CGContextSetFillColorWithColor(context, [UIColor redColor].CGColor);
CGContextFillRect(context, rectangle);
*/
/*画弧
//弧线的是通过指定两个切点,还有角度,调用CGContextAddArcToPoint()绘制
CGContextSetLineWidth(context, 2.0);
CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
CGContextMoveToPoint(context, 100, 100);
CGContextAddArcToPoint(context, 100,200, 300,200, 100);
CGContextStrokePath(context);
*/
/*
绘制贝兹曲线
//贝兹曲线是通过移动一个起始点,然后通过两个控制点,还有一个中止点,调用CGContextAddCurveToPoint() 函数绘制
CGContextSetLineWidth(context, 2.0);
CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
CGContextMoveToPoint(context, 10, 10);
CGContextAddCurveToPoint(context, 0, 50, 300, 250, 300, 400);
CGContextStrokePath(context);
*/
/*绘制二次贝兹曲线
CGContextSetLineWidth(context, 2.0);
CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
CGContextMoveToPoint(context, 10, 200);
CGContextAddQuadCurveToPoint(context, 150, 10, 300, 200);
CGContextStrokePath(context);
*/
/*绘制虚线
CGContextSetLineWidth(context, 5.0);
CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
CGFloat dashArray[] = {2,6,4,2};
CGContextSetLineDash(context, 3, dashArray, 4);//跳过3个再画虚线,所以刚开始有6-(3-2)=5个虚点
CGContextMoveToPoint(context, 10, 200);
CGContextAddQuadCurveToPoint(context, 150, 10, 300, 200);
CGContextStrokePath(context);
*/
/*绘制图片
NSString* imagePath = [[NSBundle mainBundle] pathForResource:@"dog" ofType:@"png"];
UIImage* myImageObj = [[UIImage alloc] initWithContentsOfFile:imagePath];
//[myImageObj drawAtPoint:CGPointMake(0, 0)];
[myImageObj drawInRect:CGRectMake(0, 0, 320, 480)];
NSString *s = @"我的小狗";
[s drawAtPoint:CGPointMake(100, 0) withFont:[UIFont systemFontOfSize:34.0]];
*/
/*
NSString *path = [[NSBundle mainBundle] pathForResource:@"dog" ofType:@"png"];
UIImage *img = [UIImage imageWithContentsOfFile:path];
CGImageRef image = img.CGImage;
CGContextSaveGState(context);
CGRect touchRect = CGRectMake(0, 0, img.size.width, img.size.height);
CGContextDrawImage(context, touchRect, image);
CGContextRestoreGState(context);
*/
/*NSString *path = [[NSBundle mainBundle] pathForResource:@"dog" ofType:@"png"];
UIImage *img = [UIImage imageWithContentsOfFile:path];
CGImageRef image = img.CGImage;
CGContextSaveGState(context);
CGContextRotateCTM(context, M_PI);
CGContextTranslateCTM(context, -img.size.width, -img.size.height);
CGRect touchRect = CGRectMake(0, 0, img.size.width, img.size.height);
CGContextDrawImage(context, touchRect, image);
CGContextRestoreGState(context);*/
/*
NSString *path = [[NSBundle mainBundle] pathForResource:@"dog" ofType:@"png"];
UIImage *img = [UIImage imageWithContentsOfFile:path];
CGImageRef image = img.CGImage;
CGContextSaveGState(context);
CGAffineTransform myAffine = CGAffineTransformMakeRotation(M_PI);
myAffine = CGAffineTransformTranslate(myAffine, -img.size.width, -img.size.height);
CGContextConcatCTM(context, myAffine);
CGContextRotateCTM(context, M_PI);
CGContextTranslateCTM(context, -img.size.width, -img.size.height);
CGRect touchRect = CGRectMake(0, 0, img.size.width, img.size.height);
CGContextDrawImage(context, touchRect, image);
CGContextRestoreGState(context);
*/
}
判断UITableView滚动是否到底
- (void)scrollViewDidScroll:(UIScrollView*)aScrollView { CGPointoffset = aScrollView.contentOffset;
CGRectbounds = aScrollView.bounds;
CGSizesize = aScrollView.contentSize;
UIEdgeInsetsinset = aScrollView.contentInset;
floaty = offset.y+ bounds.size.height- inset.bottom;
floath = size.height;
floatreload_distance = -20;
if(y > h + reload_distance) {
//距离到底20像 素
}
}
自定义了leftBarbuttonItem左滑返回手势失效
self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc]
initWithImage:img
style:UIBarButtonItemStylePlain
target:self
action:@selector(onBack:)];
self.navigationController.interactivePopGestureRecognizer.delegate = (id)self;
判断NSArray倒序
NSArray *tmparr = [[upLoadImageArr reverseObjectEnumerator] allObjects];
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