啟動(dòng)滑動(dòng)圖

2019-11-14 18:15:53

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供稿：網(wǎng)友

當(dāng)我們下載安裝一個(gè)新的應(yīng)用,或者將先用應(yīng)用更新之后,第一次打開會(huì)又個(gè)啟動(dòng)滑動(dòng)圖,介紹程序的功能或增加的新特性.這個(gè)界面只在第一次打開時(shí)出現(xiàn),之后就不再顯示.此處利用程序版本號(hào),以及UIScrollView和UipageControl實(shí)現(xiàn)程序啟動(dòng)滑動(dòng)圖.

程序啟動(dòng)時(shí),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(dāng)前版本號(hào)    NSString *key=(NSString *)kCFBundleVersionKey;    NSString *version=[NSBundle mainBundle].infoDictionary[key];    //上次版本存儲(chǔ)的版本號(hào)    NSString *saveVersion=[[NSUserDefaults standardUserDefaults]objectForKey:key];    //判斷版本號(hào)是否一致,如果一致,跳轉(zhuǎn)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(jìn)入啟動(dòng)滑動(dòng)頁面    else    {        //在進(jìn)入啟動(dòng)頁面之前,先把新的版本號(hào)存入沙盒,替代舊版本號(hào)        [[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(dòng)滑動(dòng)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(shè)計(jì)的比原來多一點(diǎn),目的是當(dāng)滑動(dòng)到最后一張圖時(shí),再次滑動(dòng)會(huì)進(jìn)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(gè)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(diǎn)擊跳過按鈕跳轉(zhuǎn)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(dòng)頁面

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