問(wèn)題描述

我有一個(gè)滾動(dòng)視圖，當(dāng)它上面沒(méi)有按鈕時(shí)會(huì)滾動(dòng).現(xiàn)在確實(shí)如此，并且當(dāng)拖動(dòng)鼠標(biāo)(在模擬器上)時(shí)，什么也沒(méi)有發(fā)生(我認(rèn)為是因?yàn)榘粹o被按下了).我怎樣才能做到這一點(diǎn)?

I have a scroll view that used to scroll when it didn't have buttons all over it. Now it does, and when dragging the mouse (on simulator) nothing happens (i think because the buttons are being pushed). How can I make this right?

推薦答案

發(fā)生這種情況是因?yàn)?UIScrollView 的 UIButton 子視圖(我假設(shè)按鈕作為子視圖添加到您的case) 正在跟蹤觸摸而不是滾動(dòng)視圖.UIScrollView 方法 touchesShouldCancelInContentView 是這里的關(guān)鍵.根據(jù)其描述:如果view不是UIControl對(duì)象，則默認(rèn)返回YES；否則返回NO."，即對(duì)于UIControl 對(duì)象(按鈕)，UIScrollView 不會(huì)嘗試取消阻止?jié)L動(dòng)的觸摸.

This is happening because UIButton subviews of the UIScrollView (I assume buttons are added as subviews in your case) are tracking the touches and not the scroll view. UIScrollView method touchesShouldCancelInContentView is the key here. According to its description: "The default returned value is YES if view is not a UIControl object; otherwise, it returns NO.", i.e. for UIControl objects (buttons), UIScrollView does not attempt to cancel touches which prevents scrolling.

所以，要允許使用按鈕滾動(dòng):

So, to allow scrolling with buttons:

1. 確保 UIScrollView 屬性 canCancelContentTouches 設(shè)置為 YES.
2. 子類(lèi) UIScrollView 并覆蓋 touchesShouldCancelInContentView 以在內(nèi)容視圖對(duì)象是 UIButton 時(shí)返回 YES，如下所示:

1. Make sure UIScrollView property canCancelContentTouches is set to YES.
2. Subclass UIScrollView and override touchesShouldCancelInContentView to return YES when content view object is a UIButton, like this:

- (BOOL)touchesShouldCancelInContentView:(UIView *)view
{
    if ( [view isKindOfClass:[UIButton class]] ) {
        return YES;
    }

    return [super touchesShouldCancelInContentView:view];
}

這篇關(guān)于拖動(dòng)按鈕時(shí)ScrollView不滾動(dòng)的文章就介紹到這了，希望我們推薦的答案對(duì)大家有所幫助，也希望大家多多支持html5模板網(wǎng)！