之前在服務器之家平臺給大家分享了網易首頁導航封裝類、網易首頁導航封裝類優化,今天在前兩個的基礎上仿下今日頭條。
1.網易首頁導航封裝類中主要解決了上面導航的scrollview和下面的頁面的scrollview聯動的問題,以及上面導航欄的便宜量。
2.網易首頁導航封裝類優化中主要解決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航和網易首頁導航封裝類優化相似,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、仿今日頭條滑動導航主要有3個問題:
1.uipangesturerecognizer與scrollview的手勢沖突
為了達到拖動滑動的效果，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,和網易首頁導航封裝類優化類似需要在
- (bool)gesturerecognizer:(uigesturerecognizer *)gesturerecognizer shouldrecognizesimultaneouslywithgesturerecognizer:(uigesturerecognizer *)othergesturerecognizer中根據gesturerecognizer返回yes來使scrolview和uipangesturerecognizer都識別。
2.uipangesturerecognizer滑動結束的位置不正確
用uipangesturerecognizer滑動根據便宜量來改變uinavigationcontroller的view的位置,在今日頭條中滑動結束時uinavigationcontroller的view要么在原位要么在右側，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state,根據手勢的狀態來改變uinavigationcontroller的view的位置,特別是在手勢結束時。
3.由于1使scrolview和uipangesturerecognizer都識別,導致返回時scrolview也會滑動
讓底部的scrolview能滑動的時間應該是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、 主要實現代碼(導航的代碼就不貼了,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
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_pangesturerecognizer=[[uipangesturerecognizer alloc]initwithtarget:self action:@selector(pangesture:)];_pangesturerecognizer.delegate=self;[self.navigationcontroller.view addgesturerecognizer:_pangesturerecognizer]; |
3.手勢識別的方法
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//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;}];}}//偏移量是增加的應該設為0[pan settranslation:cgpointzero inview:self.navigationcontroller.view];} |
4.手勢沖突解決
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- (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
以上所述是小編給大家分享的ios仿今日頭條滑動導航欄，希望對大家有所幫助。
