@前些天写了一篇"秘密"的Cell效果文章,但是与在工作中想要的效果还是有差距,而且扩展性很不好,于是重写封装,把整体视图都放到scrollView中,基本是和secret app 一模一样的效果了.
@代码如下:(模糊效果的类就不写了,大家可以搜"UIImage+ImageEffects",还要导入Accelerate.framework)
1.MTSecretAppEffect.h
#import <Foundation/Foundation.h> @interface MTSecretAppEffect : NSObject /** * 创建整体的scrollView,把headScrollView和tableView全部加载在上面,靠它来上下滑动,其余的滑动全部禁止 * * @return mainScrollView */ - (UIScrollView *)createMainScrollView; /** * 创建headScrollView * * @return headScrollView */ - (UIScrollView *)createHeadScrollView; /** * 创建头部的模糊view * * @param scrollview headScrollView * * @return blurImageView */ - (UIImageView *)createBlurImageViewOfView:(UIScrollView *)scrollview; /** * 在- (void)scrollViewDidScroll:(UIScrollView *)scrollView 中调用的方法 * * @param scrollView * @param mainScrollView * @param tableView * @param headScrollView * @param blurImageView */ - (void)scrollDidScrollView:(UIScrollView *)scrollView withMainScrollView:(UIScrollView *)mainScrollView withTableView:(UITableView *)tableView withHeadScrollView:(UIScrollView *)headScrollView withBlurImageView:(UIImageView *)blurImageView; @end
2.MTSecretAppEffect.m
#import "MTSecretAppEffect.h"
#import "UIImage+ImageEffects.h"
#import <QuartzCore/QuartzCore.h>
#define HEADER_HEIGHT 200.0f
#define HEADER_INIT_FRAME CGRectMake(0, 0, 320, HEADER_HEIGHT)
const CGFloat kBarHeight = 50.0f;
const CGFloat kBackgroundParallexFactor = 0.5f;
const CGFloat kBlurFadeInFactor = 0.015f;
@implementation MTSecretAppEffect
// 欠缺:调用者设置代理
- (UIScrollView *)createMainScrollView{
// 和Self.view同大小的底部ScrollView
UIScrollView *mainScrollView = [[UIScrollView alloc] initWithFrame:[UIApplication sharedApplication].keyWindow.frame];
mainScrollView.bounces = YES;
mainScrollView.alwaysBounceVertical = YES;
mainScrollView.contentSize = CGSizeZero;
mainScrollView.showsVerticalScrollIndicator = YES;
mainScrollView.scrollIndicatorInsets = UIEdgeInsetsMake(50.0f, 0, 0, 0);
return mainScrollView;
}
- (UIScrollView *)createHeadScrollView{
UIScrollView *headScrollView = [[UIScrollView alloc] initWithFrame:HEADER_INIT_FRAME];
headScrollView.scrollEnabled = NO;
headScrollView.contentSize = CGSizeMake(320, 1000);
return headScrollView;
}
- (UIImageView *)createBlurImageViewOfView:(UIScrollView *)scrollview{
UIGraphicsBeginImageContextWithOptions(scrollview.bounds.size, scrollview.opaque, 0.0);
[scrollview.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageView *blurImageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 320, HEADER_HEIGHT)];
blurImageView.image = [img applyBlurWithRadius:12 tintColor:[UIColor colorWithWhite:0.8 alpha:0.4] saturationDeltaFactor:1.8 maskImage:nil];
blurImageView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
blurImageView.alpha = 0;
blurImageView.backgroundColor = [UIColor clearColor];
return blurImageView;
}
- (void)scrollDidScrollView:(UIScrollView *)scrollView withMainScrollView:(UIScrollView *)mainScrollView withTableView:(UITableView *)tableView withHeadScrollView:(UIScrollView *)headScrollView withBlurImageView:(UIImageView *)blurImageView{
CGFloat y = 0.0f;
CGRect rect = HEADER_INIT_FRAME;
if (scrollView.contentOffset.y < 0.0f) {
// 下拉变大效果
y = fabs(MIN(0.0f, mainScrollView.contentOffset.y));
headScrollView.frame = CGRectMake(CGRectGetMinX(rect) - y / 2.0f, CGRectGetMinY(rect) - y, CGRectGetWidth(rect) + y, CGRectGetHeight(rect) + y);
}
else {
y = mainScrollView.contentOffset.y;
blurImageView.alpha = MIN(1 , y * kBlurFadeInFactor);
CGFloat backgroundScrollViewLimit = headScrollView.frame.size.height - kBarHeight;
if (y > backgroundScrollViewLimit) {
headScrollView.frame = (CGRect) {.origin = {0, y - headScrollView.frame.size.height + kBarHeight}, .size = {320, HEADER_HEIGHT}};
tableView.frame = (CGRect){.origin = {0, CGRectGetMinY(headScrollView.frame) + CGRectGetHeight(headScrollView.frame)}, .size = tableView.frame.size };
tableView.contentOffset = CGPointMake (0, y - backgroundScrollViewLimit);
CGFloat contentOffsetY = -backgroundScrollViewLimit * kBackgroundParallexFactor;
[headScrollView setContentOffset:(CGPoint){0,contentOffsetY} animated:NO];
}
else {
headScrollView.frame = rect;
tableView.frame = (CGRect){.origin = {0, CGRectGetMinY(rect) + CGRectGetHeight(rect)}, .size = tableView.frame.size };
[tableView setContentOffset:(CGPoint){0,0} animated:NO];
[headScrollView setContentOffset:CGPointMake(0, -y * kBackgroundParallexFactor)animated:NO];
}
}
}
@end
3.main.m
#import "RootViewController.h"
#import "CommentCell.h"
#import "MTSecretAppEffect.h"
#define HEADER_HEIGHT 200.0f
@interface RootViewController () <UIScrollViewDelegate, UITableViewDataSource, UITableViewDelegate>
@property (nonatomic,strong) MTSecretAppEffect *secretEffect; // secretApp 效果对象
@property (nonatomic,strong) UIScrollView *mainScrollView; // 与view相同大小的scrollView
@property (nonatomic,strong) UIScrollView *headScrollView; //
@property (nonatomic,strong) UIImageView *blurImageView; //
@property (nonatomic,strong) UITableView *tableView; //
@end
@implementation RootViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// 0.创建SecretApp effect 效果对象
self.secretEffect = [[MTSecretAppEffect alloc] init];
// 1.主底部scrollView
self.mainScrollView = [self.secretEffect createMainScrollView];
self.mainScrollView.delegate = self;
self.view = self.mainScrollView;
// 2.head背景View
self.headScrollView = [self.secretEffect createHeadScrollView];
// 3.背景图片视图
UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 320, HEADER_HEIGHT)];
imageView.image = [UIImage imageNamed:@"secret.png"];
imageView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
[self.headScrollView addSubview:imageView];
// 4.模糊视图
_blurImageView = [self.secretEffect createBlurImageViewOfView:self.headScrollView];
[self.headScrollView addSubview:_blurImageView];
// 5.tableView
self.tableView = [[UITableView alloc] initWithFrame:CGRectMake(0, HEADER_HEIGHT, CGRectGetWidth(self.view.frame), CGRectGetHeight(self.view.frame) - 50 ) style:UITableViewStylePlain];
self.tableView.scrollEnabled = NO;
self.tableView.delegate = self;
self.tableView.dataSource = self;
self.tableView.tableFooterView = [[UIView alloc] initWithFrame:CGRectZero];
self.tableView.separatorColor = [UIColor clearColor];
// 6.添加视图
[self.view addSubview:self.headScrollView];
[self.view addSubview:self.tableView];
// 7.设置一下
self.mainScrollView.contentSize = CGSizeMake(320, self.tableView.contentSize.height + CGRectGetHeight(self.headScrollView.frame));
}
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
// 8.调用方法
[self.secretEffect scrollDidScrollView:scrollView withMainScrollView:self.mainScrollView withTableView:self.tableView withHeadScrollView:self.headScrollView withBlurImageView:self.blurImageView];
}
#pragma mark - 隐藏状态栏
- (BOOL)prefersStatusBarHidden {
return YES;
}
#pragma mark - UITableView dataSource
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return 20;
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
return 40;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
CommentCell *cell = [tableView dequeueReusableCellWithIdentifier:[NSString stringWithFormat:@"Cell %ld", indexPath.row]];
if (!cell) {
cell = [[CommentCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:[NSString stringWithFormat:@"Cell %ld", indexPath.row]];
}
cell.textLabel.text = [NSString stringWithFormat:@"section = %ld row = %ld",indexPath.section,indexPath.row];
return cell;
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end
@效果图:
iOS开发之剖析"秘密"App内容页面效果(二),布布扣,bubuko.com
原文地址：http://blog.csdn.net/hmt20130412/article/details/38337631
