啟動滑動圖

2019-11-14 18:15:53

字體：大中小

來源：轉載

供稿：網友

當我們下載安裝一個新的應用,或者將先用應用更新之后,第一次打開會又個啟動滑動圖,介紹程序的功能或增加的新特性.這個界面只在第一次打開時出現,之后就不再顯示.此處利用程序版本號,以及UIScrollView和UipageControl實現程序啟動滑動圖.

程序啟動時,最先打開的是入口類:AppDelegate,所以先在入口類中判斷程序是否為第一次打開.

//獲取當前版本號    NSString *key=(NSString *)kCFBundleVersionKey;    NSString *version=[NSBundle mainBundle].infoDictionary[key];    //上次版本存儲的版本號    NSString *saveVersion=[[NSUserDefaults standardUserDefaults]objectForKey:key];    //判斷版本號是否一致,如果一致,跳轉到主頁    if ([version isEqualToString:saveVersion]) {        mainViewController *main=[[mainViewController alloc]init];        UIWindow *window=[UIapplication sharedApplication].delegate.window;        window.rootViewController=main;    }    //如果不一致,進入啟動滑動頁面    else    {        //在進入啟動頁面之前,先把新的版本號存入沙盒,替代舊版本號        [[NSUserDefaults standardUserDefaults]setObject:version forKey:key];        [[NSUserDefaults standardUserDefaults]synchronize];        scrollViewController *scroll=[[scrollViewController alloc]init];        UIWindow *window=[UIApplication sharedApplication].delegate.window;        window.rootViewController=scroll;    }

在啟動滑動頁面添加UIScorllVIew和UIPageControl

添加UIScrollView-(void)addScorll{    scroll=[[UIScrollView alloc]initWithFrame:CGRectMake(0, 0, 320, 480)];    scroll.pagingEnabled=YES;    //將scroll的大小設計的比原來多一點,目的是當滑動到最后一張圖時,再次滑動會進入主界面,沒有為什么,我自己試出來的.    scroll.contentSize=CGSizeMake(320*3+150, 0);    //添加圖片    for (int i=0; i<3; i++) {        UIImageView *image=[[UIImageView alloc]initWithFrame:CGRectMake(320*i, 0, 320, 480)];        image.image=[UIImage imageNamed:[NSString stringWithFormat:@"%d.png",i+1]];        [scroll addSubview:image];        //為每個頁面添加跳過按鈕        UIButton *jump=[UIButton buttonWithType:UIButtonTypeCustom];        jump.frame=CGRectMake(320*i+110, 430, 100, 30);        jump.backgroundColor=[UIColor redColor];        [jump addTarget:self action:@selector(jumpToMain) forControlEvents:UIControlEventTouchUpInside];        [scroll addSubview:jump];    }    scroll.showsHorizontalScrollIndicator=NO;    scroll.contentOffset=CGPointMake(0, 0);    scroll.delegate=self;    [self.view addSubview:scroll];}

點擊跳過按鈕跳轉到下一頁

-(void)jumpToMain{    mainViewController *main=[[mainViewController alloc]init];    UIWindow *window=[UIApplication sharedApplication].delegate.window;    window.rootViewController=main;}

添加pagecontrol

-(void)addpagecontrl{    page=[[UIPageControl alloc]init];    page.frame=CGRectMake(110, 470, 100, 10);    page.numberOfPages=3;    page.currentPage=0;    [self.view addSubview:page];}

滑動頁面

-(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{    page.currentPage=scroll.contentOffset.x/320;    //第三張圖像向左需要滑動超過140才能跳轉,這個隨個人情況調吧    if (scroll.contentOffset.x>320*2+140) {        mainViewController *main=[[mainViewController alloc]init];        UIWindow *window=[UIApplication sharedApplication].delegate.window;        window.rootViewController=main;    }}