IOS仿今日頭條滑動導(dǎo)航欄

更新時間：2016年01月28日 15:22:11 作者：小崔

今天仿今日頭條滑動導(dǎo)航和網(wǎng)易首頁導(dǎo)航封裝類優(yōu)化相似,這個也是解決手勢沖突,UIPanGestureRecognizer與ScrollView的手勢沖突

之前在腳本之家平臺給大家分享了網(wǎng)易首頁導(dǎo)航封裝類、網(wǎng)易首頁導(dǎo)航封裝類優(yōu)化,今天在前兩個的基礎(chǔ)上仿下今日頭條。

1.網(wǎng)易首頁導(dǎo)航封裝類中主要解決了上面導(dǎo)航的ScrollView和下面的頁面的ScrollView聯(lián)動的問題,以及上面導(dǎo)航欄的便宜量。

2.網(wǎng)易首頁導(dǎo)航封裝類優(yōu)化中主要解決iOS7以上滑動返回功能中UIScreenEdgePanGestureRecognizer與ScrollView的滑動的手勢沖突問題。

今天仿今日頭條滑動導(dǎo)航和網(wǎng)易首頁導(dǎo)航封裝類優(yōu)化相似,這個也是解決手勢沖突,UIPanGestureRecognizer與ScrollView的手勢沖突。

一、ViewController的層次

用上面的圖來介紹,左側(cè)的個人頁面ViewController上面通過addChildViewController添加了一個以MainViewController為RootViewController的

UINavigationController,通過addSubview將UINavigationController的View添加到個人頁面ViewController的View上。

二、仿今日頭條滑動導(dǎo)航主要有3個問題:

1.UIPanGestureRecognizer與ScrollView的手勢沖突

為了達(dá)到拖動滑動的效果，需要給MainViewController添加一個UIPanGestureRecognizer,由于底部是ScrollView和TableView組成的，所以會使UIPanGestureRecognizer與底部的沖突,和網(wǎng)易首頁導(dǎo)航封裝類優(yōu)化類似需要在

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer中根據(jù)gestureRecognizer返回YES來使ScrolView和UIPanGestureRecognizer都識別。

2.UIPanGestureRecognizer滑動結(jié)束的位置不正確

用UIPanGestureRecognizer滑動根據(jù)便宜量來改變UINavigationController的View的位置,在今日頭條中滑動結(jié)束時UINavigationController的View要么在原位要么在右側(cè)，不會停在中間,這個問題讓我想起了之前做的果凍效果,手勢有狀態(tài)state,根據(jù)手勢的狀態(tài)來改變UINavigationController的View的位置,特別是在手勢結(jié)束時。

3.由于1使ScrolView和UIPanGestureRecognizer都識別,導(dǎo)致返回時ScrolView也會滑動

讓底部的ScrolView能滑動的時間應(yīng)該是UINavigationController的View在初始位置frame的x為0，所以在它的frame的x>0時,底部的bottomScrollView的scrollEnabled=NO。

三、主要實現(xiàn)代碼(導(dǎo)航的代碼就不貼了,只貼主要的)

1.聲明一個拖動手勢

@property(nonatomic,strong) UIPanGestureRecognizer *panGestureRecognizer;

2.為MainViewController添加手勢

_panGestureRecognizer=[[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(panGesture:)];
_panGestureRecognizer.delegate=self;
[self.navigationController.view addGestureRecognizer:_panGestureRecognizer];

3.手勢識別的方法

//平移
-(void)panGesture:(UIPanGestureRecognizer*)pan
{
//在View中的位置
// CGPoint point=[pan locationInView:self.navigationController.view];
//在View中的移動量 以手指按下的為原點
CGPoint point1=[pan translationInView:self.navigationController.view];
if (pan.state==UIGestureRecognizerStateChanged&&pan==_panGestureRecognizer) {
if (point1.x>0&&self.navigationController.view.frame.origin.x<self.navigationController.view.frame.size.width-100) {
float x= self.navigationController.view.frame.origin.x+point1.x>self.navigationController.view.frame.size.width-100?self.navigationController.view.frame.size.width-100:self.navigationController.view.frame.origin.x+point1.x;
self.navigationController.view.frame=CGRectMake(x, self.navigationController.view.frame.origin.y, self.navigationController.view.frame.size.width, self.navigationController.view.frame.size.height);
NSLog(@"%@",NSStringFromCGRect(self.navigationController.view.frame));
}
else if(point1.x<0)
{
NSLog(@"aaa %f",self.navigationController.view.frame.origin.x);
float x=self.navigationController.view.frame.origin.x+point1.x<0?0:self.navigationController.view.frame.origin.x+point1.x;
self.navigationController.view.frame=CGRectMake(x, self.navigationController.view.frame.origin.y, self.navigationController.view.frame.size.width, self.navigationController.view.frame.size.height);
}
}
else if(pan.state==UIGestureRecognizerStateEnded)
{
if (self.navigationController.view.frame.origin.x>self.navigationController.view.frame.size.width/3) {
[UIView animateWithDuration:0.2 animations:^{
self.navigationController.view.frame=CGRectMake(self.navigationController.view.frame.size.width-100, 0, self.navigationController.view.frame.size.width, self.navigationController.view.frame.size.height);
} completion:^(BOOL finished) {
self.bottomScrollView.scrollEnabled=YES;
}];
}
else
{
[UIView animateWithDuration:0.2 animations:^{
self.navigationController.view.frame=CGRectMake(0, 0, self.navigationController.view.frame.size.width, self.navigationController.view.frame.size.height);
} completion:^(BOOL finished) {
self.bottomScrollView.scrollEnabled=YES;
}];
}
}
//偏移量是增加的應(yīng)該設(shè)為0
[pan setTranslation:CGPointZero inView:self.navigationController.view];
}

4.手勢沖突解決

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
if (self.bottomScrollView.contentOffset.x<=0.0&&gestureRecognizer==_panGestureRecognizer) {
if (self.navigationController.view.frame.origin.x>0) {
self.bottomScrollView.scrollEnabled=NO;
}
else
{
self.bottomScrollView.scrollEnabled=YES;
}
return YES;
}
return NO;
}

四、效果圖