gpt4 book ai didi

iOS实现贝塞尔曲线动画

转载 作者:qq735679552 更新时间:2022-09-27 22:32:09 33 4
gpt4 key购买 nike

CFSDN坚持开源创造价值,我们致力于搭建一个资源共享平台,让每一个IT人在这里找到属于你的精彩世界.

这篇CFSDN的博客文章iOS实现贝塞尔曲线动画由作者收集整理,如果你对这篇文章有兴趣,记得点赞哟.

本文实例为大家分享了ios实现贝塞尔曲线动画的具体代码,供大家参考,具体内容如下 。

效果如图:

iOS实现贝塞尔曲线动画

仿美人相机,手势滑动隐藏顶部view。为了方便讲解,将屏幕分为几个区域,如图:

iOS实现贝塞尔曲线动画

在拖动过程中:

1、拖动距离小于minmovedistance,贝赛尔曲线发生形变 2、拖动大于minmovedistance,整个view开始下移 。

在松开手时:

1、拖动距离小于minmovedistance,未发生位移,贝塞尔曲线恢复形变 2、拖动大于minmovedistance,小于mindisappeardistance,贝塞尔曲线恢复形变、位移回到初始位置。 3、拖动大于mindisappeardistance,向下移动隐藏view 。

1、根据y轴位移量确定贝塞尔路径

在拖动时曲线形变、松手时曲线恢复形变的时候都需要改变贝塞尔曲线,实际上是改变二阶贝塞尔曲线的控制点,因此写一个方法,根据传入的y轴位移量得到新的贝塞尔路径:

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
- (cgpathref)getpathwithmovedistance:(cgfloat)distance{
 
     uibezierpath *path = [uibezierpath bezierpath];
     cgpoint startpoint = cgpointmake(0, 0);
     cgpoint controlpoint = cgpointmake(self.bounds.size.width*0.5, 60+distance);
     cgpoint endpoint = cgpointmake(self.bounds.size.width, 0);
 
     [path movetopoint:startpoint];
     [path addquadcurvetopoint:endpoint controlpoint:controlpoint];
 
     [path addlinetopoint:cgpointmake(self.bounds.size.width, self.bounds.size.height)];
     [path addlinetopoint:cgpointmake(0, self.bounds.size.height)];
 
     return path.cgpath;
}

2、初始化图形

初始化的时候,可以根据上一步的方法,传入位移量0,获取贝塞尔路径,并将获得的路径赋给cashapelayer:

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
- (id)initwithframe:(cgrect)frame{
     if (self = [super initwithframe:frame]) {
         self.originy = frame.origin.y;
         [self setuplayer];
         [self addgesure];
     }
     return self;
}
 
- ( void )setuplayer{
     self.toplinelayer = [cashapelayer layer];
     self.toplinelayer.fillcolor = colorfortheme.cgcolor;
     self.toplinelayer.strokecolor = colorfortheme.cgcolor;
     self.toplinelayer.path = [self getpathwithmovedistance:0];
     [self.layer addsublayer:self.toplinelayer];
}

3、添加手势

添加uipangesturerecognizer拖动手势,并处理手势拖动和结束拖动的事件.

拖动时:

1、拖动距离小于minmovedistance,只有贝赛尔曲线发生形变,调用步奏一中的方法。 2、拖动距离大于minmovedistance,整个view开始下移 。

结束拖动时:

调用revertformy:方法,传入当前在y轴上已经发生的位移量 。

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
- ( void )addgesure{
     if (self.gesture == nil) {
         self.gesture = [[uipangesturerecognizer alloc] initwithtarget:self action:@selector(handlepan:)];
     }
     [self addgesturerecognizer:self.gesture];
}
 
- ( void )handlepan:(uipangesturerecognizer *)gesture{
     cgfloat distancex = [gesture translationinview:self].x;
     cgfloat distancey = [gesture translationinview:self].y;
 
     if ( abs (distancex) > abs (distancey)) {
         return ;
     }
     //拖动过程
     if (gesture.state == uigesturerecognizerstatechanged) {
         nslog(@ "%f" ,distancey);
 
         //移动少于minmovedistance,贝赛尔曲线形变
         if (distancey > 0 && distancey <= minmovedistance) {
             self.toplinelayer.path = [self getpathwithmovedistance:distancey];
         }
         //移动大于minmovedistance,整个view下移
         else if (distancey > minmovedistance) {
             self.frame = cgrectmake(0, self.originy+distancey-minmovedistance, self.bounds.size.width, self.bounds.size.height);
         }
     }
     //手势结束
     if (gesture.state == uigesturerecognizerstateended || gesture.state == uigesturerecognizerstatecancelled || gesture.state == uigesturerecognizerstatefailed) {
         [self removegesturerecognizer:self.gesture];
         [self revertformy:distancey];
     }
}

4、revertformy:恢复形变方法

根据传入的y轴上的位移量,实现不同的效果:

1、y小于minmovedistance,未发生位移,贝塞尔曲线恢复形变 2、y大于minmovedistance,小于mindisappeardistance,贝塞尔曲线恢复形变、位移回到初始位置。 3、y大于mindisappeardistance,向下移动隐藏view 。

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
//手势结束后恢复或隐藏
-( void )revertformy:(cgfloat)y{
 
     //y < 最小的隐藏位移距离,未发生位移,贝塞尔曲线恢复动画
     if (y < mindisappeardistance) {
         cakeyframeanimation *vibrate = [cakeyframeanimation animationwithkeypath:@ "path" ];
         vibrate.timingfunction = [camediatimingfunction functionwithname:kcamediatimingfunctioneasein];
         vibrate.values = @[
                            (id) [self getpathwithmovedistance:y],
                            (id) [self getpathwithmovedistance:-(y * 0.3)],
                            (id) [self getpathwithmovedistance:(y * 0.2)],
                            (id) [self getpathwithmovedistance:-(y * 0.15)],
                            (id) [self getpathwithmovedistance:(y * 0.1)],
                            (id) [self getpathwithmovedistance:-(y * 0.07)],
                            (id) [self getpathwithmovedistance:(y * 0.05)],
                            (id) [self getpathwithmovedistance:0.0]
                            ];
         vibrate.duration = 0.5;
         vibrate.removedoncompletion = no;
         vibrate.fillmode = kcafillmodeforwards;
         vibrate.delegate = self;
         [self.toplinelayer addanimation:vibrate forkey:nil];
     }
 
     //y > 最小位移距离,发生了位移
     if (y > minmovedistance){
         [uiview animatewithduration:0.3 animations:^{
             cgfloat endy;
             //向上恢复view
             if (y < mindisappeardistance) {
                 endy = self.originy;
             }
             //向下隐藏view
             else {
                 endy = screen_height;
             }
             self.frame = cgrectmake(0, endy, screen_width, self.frame.size.height);
         }];
     }
}

5、双击屏幕空白,消失的view从底部上移,恢复到初始位置

这个只是为了回到初始状态,根据实际需求实现.

?
1
2
3
4
5
6
7
8
9
10
11
12
//恢复到初始位置
- ( void )comeback{
     if (self.frame.origin.y <= self.originy) {
         return ;
     }
 
     [uiview animatewithduration:0.3 animations:^{
         self.frame = cgrectmake(0, self.originy, screen_width, self.frame.size.height);
     } completion:^( bool finished) {
         [self revertformy:10];
     }];
}

完整代码 。

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持我.

原文链接:https://blog.csdn.net/dolacmeng/article/details/79276039 。

最后此篇关于iOS实现贝塞尔曲线动画的文章就讲到这里了,如果你想了解更多关于iOS实现贝塞尔曲线动画的内容请搜索CFSDN的文章或继续浏览相关文章,希望大家以后支持我的博客! 。

33 4 0
Copyright 2021 - 2024 cfsdn All Rights Reserved 蜀ICP备2022000587号
广告合作:1813099741@qq.com 6ren.com