IOS开发之手势

最新推荐文章于 2024-07-07 13:49:08 发布

铜和尚

最新推荐文章于 2024-07-07 13:49:08 发布

阅读量553

点赞数

分类专栏： IOS开发文章标签： ios开发手势识别实例移动 slide

本文链接：https://blog.youkuaiyun.com/yunshixin/article/details/40196361

版权

IOS开发专栏收录该内容

5 篇文章

订阅专栏

在IOS系统3.2过后apple公司提供了一个抽象类，UIGestureRecognizer类用于手势识别，它的子类有主要有六个分别是：

UITapGestureRecognizer（轻击一下）

UIPinchGestureRecognizer（两指控制的缩放）

UIRotationGestureRecognizer（旋转）

UISwipeGestureRecognizer（滑动，快速移动）

UIPanGestureRecognizer（拖移，慢慢移动）

UILongPressGestureRecognizer（长按）

继承关系如下：

手势的使用

1.创建手势的实例。当创建手势时，指定一个回调方法，当手势开始，改变、或结束时，回调方法被调用。

2.将实例添加到需要识别的view中，每个手势只对应一个view，但每个view可对应多个手势，当手势发生在view 边界内时，回调方法。

在虚拟机上调试时有可能会不灵敏，因此尽量在真机上运行，尤其是多指手势。

******************************************可耻的分割线********************************************************

UITapGestureRecognizer使用

UITapGestureRecognizer *tap = [

[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(huidiaohanshu:)];

[self.view addGestureRecognizer:tap];

以上内容添加到viewcontroller里面的viewDidLoad函数中，然后再定义huidiaohanshu参数就是tap,

如下

-（void）huidiaohanshu：（UITapGestureRecognizer *）tap

｛

//使用手势你想要达到的效果

｝

******************************************可耻的分割线********************************************************

UIPinchGestureRecognizer使用

UIPinchGestureRecognizer *pinch = [[UIPinchGestureRecognizer alloc]initWithTarget:self action:@selector(huidiaohanshu:)];

[self.view addGestureRecognizer:pinch];

以上内容添加到viewcontroller里面的viewDidLoad函数中，然后再定义huidiaohanshu参数就是pinch,

如下

-（void）huidiaohanshu：（UIPinchGestureRecognizer *）

｛

scale = pinchGestureRecognizer.scale;

[self transformImageView];

if (pinchGestureRecognizer.state == UIGestureRecognizerStated)

{

previousScale == scale*previousScale;

scale = 1;

}

其中scale和previousScale是预先定义好的实例变量，scale代表当前的缩放比例，previousScale代表先前的缩放比例。

******************************************可耻的分割线********************************************************

UIRotationGestureRecognizer使用

UIRotationGestureRecognizer *rotation = [[UIRotationGestureRecognizer alloc]initWithTarget:self action:@selector(huidiaohanshu:)];

[self.view addGestureRecognizer:rotation];

以上内容添加到viewcontroller里面的viewDidLoad函数中，然后再定义huidiaohanshu参数就是rotation,

如下

-（void）huidiaohanshu：（UIRotationGestureRecognizer *）rotation

｛

rotation = rotationGestureRecognizer.rotation;

[self transformImageView];

if(rotationGestureRecognizer.state == UIGestureRecognizerStateEnded)

{

previousrotation = rotation+prevoiusrotation;

rotation = 0;

}

其中rotation和previousrotation是预先定义好的实例变量，rotation代表当前的缩放比例，previousrotation代表先前的缩放比例。

******************************************可耻的分割线********************************************************

UISwipeGestureRecognizer的使用

UISwipeGestureRecognizer *swipe = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(huidiaohanshu:)];

swipe.direction = UISwipeGestureRecognizerDirectionUp | UISwipeGestureRecognizerDirectionDown；//如果需要横向的就用Left | Right

[self.view addGestureRecognizer:swipe];

以上内容添加到viewcontroller里面的viewDidLoad函数中，然后再定义huidiaohanshu参数就是swipe如下

-（void）huidiaohanshu：（UISwipeGestureRecognizer *）swipe

{

//使用手势所要达到的效果

}

******************************************可耻的分割线********************************************************

UIPanGestureRecognizer的使用

UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(huidiaohanshu:)];

[self.view addGestureRecognizer:pan];

以上内容添加到viewcontroller里面的viewDidLoad函数中，然后再定义huidiaohanshu参数就是pan,

如下

-（void）huidiaohanshu：（UIPanGestureRecognizer *）panGestureRecognize

{

//使用手势所要达到的效果
    CGPoint translation = [panGestureRecognize translationInView:self.view];
   panGestureRecognize.view.center = CGPointMake(panGestureRecognize.view.center.x + translation.x,
                                       panGestureRecognize.view.center.y + translation.y);
    [panGestureRecognize setTranslation:CGPointZero inView:self.view];

    if (panGestureRecognize.state == UIGestureRecognizerStateEnded) {

        CGPoint velocity = [panGestureRecognize velocityInView:self.view];
        CGFloat magnitude = sqrtf((velocity.x * velocity.x) + (velocity.y * velocity.y));
        CGFloat slideMult = magnitude / 200;
        NSLog(@"magnitude: %f, slideMult: %f", magnitude, slideMult);

        float slideFactor = 0.1 * slideMult; // Increase for more of a slide
        CGPoint finalPoint = CGPointMake(panGestureRecognize.view.center.x + (velocity.x * slideFactor),
                                         panGestureRecognize.view.center.y + (velocity.y * slideFactor));
        finalPoint.x = MIN(MAX(finalPoint.x, 0), self.view.bounds.size.width);
        finalPoint.y = MIN(MAX(finalPoint.y, 0), self.view.bounds.size.height);

        [UIView animateWithDuration:slideFactor*2 delay:0 options:UIViewAnimationOptionCurveEaseOut animations:^{
            panGestureRecognize.view.center = finalPoint;
        } completion:nil];

}

以上代码解析：

计算速度向量的长度（估计大部分都忘了）这些知识了。
如果速度向量小于200，那就会得到一个小于的小数，那么滑行会很短
基于速度和速度因素计算一个终点
确保终点不会跑出父View的边界
使用UIView动画使view滑动到终点

******************************************可耻的分割线********************************************************

UILongPressGestureRecognizer的使用

UILongPressGestureRecognizer *longpress = [[UILongPressGestureRecognizer alloc]initWithTarget:self action:@selector(huidiaohanshu:)];

longpress.minimumPressDuration = 1.0;

[self.view addGestureRecognizer:longpress];

以上内容添加到viewcontroller里面的viewDidLoad函数中，然后再定义huidiaohanshu参数就是longpress如下

-（void）huidiaohanshu：（UILongPressGestureRecognizer *）longpress

{

if(longpress.state == UIGestureRecognizerStateBegan)

{

CGPoint point = [longpress locationInView:self.tableView];

if(indexPath == nil)

return;

//使用手势所要达到的效果

}

******************************************可耻的分割线********************************************************

自定义手势

继承UIGestureRecognizer，并实现以下方法

-touchesBegan:withEvent:

-touchesMoved:withEvent:

-touchesEnded:withEvent:

-touchesCancelled:withEvent:

具体如下：

新建一个类，继承UIGestureRecognizer，代码如下：

.h文件

************************************************************

#import
typedef enum {
    DirectionUnknown = 0,
    DirectionLeft,
    DirectionRight
} Direction;

@interface HappyGestureRecognizer : UIGestureRecognizer
@property (assign) int tickleCount;
@property (assign) CGPoint curTickleStart;
@property (assign) Direction lastDirection;

@end

************************************************************************

.m文件

**************************************************************************************

#import "HappyGestureRecognizer.h"
#import
#define REQUIRED_TICKLES 2
#define MOVE_AMT_PER_TICKLE 25

@implementation HappyGestureRecognizer

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch * touch = [touches anyObject];
self.curTickleStart = [touch locationInView:self.view];
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {

    // Make sure we've moved a minimum amount since curTickleStart
    UITouch * touch = [touches anyObject];
    CGPoint ticklePoint = [touch locationInView:self.view];
    CGFloat moveAmt = ticklePoint.x - self.curTickleStart.x;
    Direction curDirection;
    if (moveAmt < 0) {
        curDirection = DirectionLeft;
    } else {
        curDirection = DirectionRight;
    }
    if (ABS(moveAmt) < MOVE_AMT_PER_TICKLE) return;

    // 确认方向改变了
    if (self.lastDirection == DirectionUnknown ||
        (self.lastDirection == DirectionLeft && curDirection == DirectionRight) ||
        (self.lastDirection == DirectionRight && curDirection == DirectionLeft)) {

        // 挠痒次数
        self.tickleCount++;
        self.curTickleStart = ticklePoint;
        self.lastDirection = curDirection;

        // 一旦挠痒次数超过指定数，设置手势为结束状态
        // 这样回调函数会被调用。
        if (self.state == UIGestureRecognizerStatePossible && self.tickleCount > REQUIRED_TICKLES) {
            [self setState:UIGestureRecognizerStateEnded];
        }
    }

}

- (void)reset {
    self.tickleCount = 0;
    self.curTickleStart = CGPointZero;
    self.lastDirection = DirectionUnknown;
    if (self.state == UIGestureRecognizerStatePossible) {
        [self setState:UIGestureRecognizerStateFailed];
    }
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
[self reset];
}

- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
[self reset];
}

@end

**************************************************************************************

调用自定义手势和以前一样

HappyGestureRecognizer *happy = [[HappyGestureRecognizer alloc]initWithTarget:self action:@selector(handleHappy:)];

[self.view addGestureRecognizer:happy];

回调函数

-(void)handleHappy:(HappyGestureRecognizer *)happy

{

//所要达到的效果

}