识别用户手势的路径

时间:2013-01-04 16:57:29

标签: objective-c ios

我正在开发一个在屏幕上有9个视图的应用程序,我希望用户以他们想要的方式连接视图,并将其序列记录为密码。 但我不知道应该使用哪种手势识别器。

我应该使用CMUnistrokeGestureRecognizer还是几个滑动手势或其他任何东西的组合? 感谢。

2 个答案:

答案 0 :(得分:4)

您可以使用UIPanGestureRecognizer,例如:

CGFloat const kMargin = 10;

- (void)viewDidLoad
{
    [super viewDidLoad];

    // create a container view that all of our subviews for which we want to detect touches are:

    CGFloat containerWidth = fmin(self.view.bounds.size.width, self.view.bounds.size.height) - kMargin * 2.0;

    UIView *container = [[UIView alloc] initWithFrame:CGRectMake(kMargin, kMargin, containerWidth, containerWidth)];
    container.backgroundColor = [UIColor darkGrayColor];
    [self.view addSubview:container];

    // now create all of the subviews, specifying a tag for each; and

    CGFloat cellWidth = (containerWidth - (4.0 * kMargin)) / 3.0;

    for (NSInteger column = 0; column < 3; column++)
    {
        for (NSInteger row = 0; row < 3; row++)
        {
            UIView *cell = [[UIView alloc] initWithFrame:CGRectMake(kMargin + column * (cellWidth + kMargin),
                                                                    kMargin + row    * (cellWidth + kMargin),
                                                                    cellWidth, cellWidth)];
            cell.tag = row * 3 + column;
            cell.backgroundColor = [UIColor lightGrayColor];
            [container addSubview:cell];
        }
    }

    // finally, create the gesture recognizer

    UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self
                                                                          action:@selector(handlePan:)];
    [container addGestureRecognizer:pan];
}

- (void)handlePan:(UIPanGestureRecognizer *)gesture
{
    static NSMutableArray *gesturedSubviews;

    // if we're starting a gesture, initialize our list of subviews that we've gone over

    if (gesture.state == UIGestureRecognizerStateBegan)
    {
        gesturedSubviews = [NSMutableArray array];
    }

    // now figure out whether:
    //   (a) are we over a subview; and
    //   (b) is this a different subview than we last were over

    CGPoint location = [gesture locationInView:gesture.view];

    for (UIView *subview in gesture.view.subviews)
    {
        if (CGRectContainsPoint(subview.frame, location))
        {
            if (subview != [gesturedSubviews lastObject])
            {
                [gesturedSubviews addObject:subview];

                // an example of the sort of graphical flourish to give the
                // some visual cue that their going over the subview in question 
                // was recognized

                [UIView animateWithDuration:0.25
                                      delay:0.0
                                    options:UIViewAnimationOptionAutoreverse
                                 animations:^{
                                     subview.alpha = 0.5;
                                 }
                                 completion:^(BOOL finished){
                                     subview.alpha = 1.0;
                                 }];
            }
        }
    }

    // finally, when done, let's just log the subviews
    // you would do whatever you would want here

    if (gesture.state == UIGestureRecognizerStateEnded)
    {
        NSLog(@"We went over:");

        for (UIView *subview in gesturedSubviews)
        {
            NSLog(@"  %d", subview.tag);
        }

        // you might as well clean up your static variable when you're done

        gesturedSubviews = nil;
    }
}

显然,您可以按照自己想要的方式创建子视图,并以任何方式跟踪它们,但想法是让子视图具有唯一的tag个数字,并且手势识别器只会看到哪个顺序你只需一个动作即可完成它们。

即使我没有准确捕捉到您想要的内容,它至少会向您展示如何使用平移手势识别器来跟踪手指从一个子视图到另一个子视图的移动。


<强>更新

如果您想在用户登录时在屏幕上绘制路径,则可以使用CAShapeLayer创建UIBezierPath。我将在下面进行演示,但作为一个警告,我不得不指出这可能不是一个很好的安全功能:通常使用密码输入,您将向用户展示足够的信息,以便他们可以确认他们正在做他们想要什么,但还不够,以便有人可以看一眼他们的肩膀,看看整个密码是什么。输入文本密码时,通常iOS会立即显示您点击的最后一个键,但很快就会将其变成星号,以便您在任何时候都看不到整个密码。因此我的初步建议。

但是如果你真的有心在向用户展示绘制它的路径,你可以使用类似下面的内容。首先,这需要Quartz 2D。因此,将QuartzCore.framework添加到您的项目中(请参阅Linking to a Library or Framework)。其次,导入QuartCore标题:

#import <QuartzCore/QuartzCore.h>

第三,用以下内容替换pan处理程序:

- (void)handlePan:(UIPanGestureRecognizer *)gesture
{
    static NSMutableArray *gesturedSubviews;
    static UIBezierPath *path = nil;
    static CAShapeLayer *shapeLayer = nil;

    // if we're starting a gesture, initialize our list of subviews that we've gone over

    if (gesture.state == UIGestureRecognizerStateBegan)
    {
        gesturedSubviews = [NSMutableArray array];
    }

    // now figure out whether:
    //   (a) are we over a subview; and
    //   (b) is this a different subview than we last were over

    CGPoint location = [gesture locationInView:gesture.view];

    for (UIView *subview in gesture.view.subviews)
    {
        if (!path)
        {
            // if the path hasn't be started, initialize it and the shape layer

            path = [UIBezierPath bezierPath];
            [path moveToPoint:location];
            shapeLayer = [[CAShapeLayer alloc] init];
            shapeLayer.strokeColor = [UIColor redColor].CGColor;
            shapeLayer.fillColor = [UIColor clearColor].CGColor;
            shapeLayer.lineWidth = 2.0;
            [gesture.view.layer addSublayer:shapeLayer];
        }
        else
        {
            // otherwise add this point to the layer's path

            [path addLineToPoint:location];
            shapeLayer.path = path.CGPath;
        }

        if (CGRectContainsPoint(subview.frame, location))
        {
            if (subview != [gesturedSubviews lastObject])
            {
                [gesturedSubviews addObject:subview];

                [UIView animateWithDuration:0.25
                                      delay:0.0
                                    options:UIViewAnimationOptionAutoreverse
                                 animations:^{
                                     subview.alpha = 0.5;
                                 }
                                 completion:^(BOOL finished){
                                     subview.alpha = 1.0;
                                 }];
            }
        }
    }

    // finally, when done, let's just log the subviews
    // you would do whatever you would want here

    if (gesture.state == UIGestureRecognizerStateEnded)
    {
        // assuming the tags are numbers between 0 and 9 (inclusive), we can build the password here

        NSMutableString *password = [NSMutableString string];

        for (UIView *subview in gesturedSubviews)
            [password appendFormat:@"%c", subview.tag + 48];

        NSLog(@"Password = %@", password);

        // clean up our array of gesturedSubviews

        gesturedSubviews = nil;

        // clean up the drawing of the path on the screen the user drew

        [shapeLayer removeFromSuperlayer];
        shapeLayer = nil;
        path = nil;
    }
}

这会产生用户在手势进行时绘制的路径:

path of user's finger

不是显示用户使用用户手指的每次移动绘制的路径,也许您只需在子视图的中心之间绘制线条,例如:

- (void)handlePan:(UIPanGestureRecognizer *)gesture
{
    static NSMutableArray *gesturedSubviews;
    static UIBezierPath *path = nil;
    static CAShapeLayer *shapeLayer = nil;

    // if we're starting a gesture, initialize our list of subviews that we've gone over

    if (gesture.state == UIGestureRecognizerStateBegan)
    {
        gesturedSubviews = [NSMutableArray array];
    }

    // now figure out whether:
    //   (a) are we over a subview; and
    //   (b) is this a different subview than we last were over

    CGPoint location = [gesture locationInView:gesture.view];

    for (UIView *subview in gesture.view.subviews)
    {
        if (CGRectContainsPoint(subview.frame, location))
        {
            if (subview != [gesturedSubviews lastObject])
            {
                [gesturedSubviews addObject:subview];

                if (!path)
                {
                    // if the path hasn't be started, initialize it and the shape layer

                    path = [UIBezierPath bezierPath];
                    [path moveToPoint:subview.center];
                    shapeLayer = [[CAShapeLayer alloc] init];
                    shapeLayer.strokeColor = [UIColor redColor].CGColor;
                    shapeLayer.fillColor = [UIColor clearColor].CGColor;
                    shapeLayer.lineWidth = 2.0;
                    [gesture.view.layer addSublayer:shapeLayer];
                }
                else
                {
                    // otherwise add this point to the layer's path

                    [path addLineToPoint:subview.center];
                    shapeLayer.path = path.CGPath;
                }

                [UIView animateWithDuration:0.25
                                      delay:0.0
                                    options:UIViewAnimationOptionAutoreverse
                                 animations:^{
                                     subview.alpha = 0.5;
                                 }
                                 completion:^(BOOL finished){
                                     subview.alpha = 1.0;
                                 }];
            }
        }
    }

    // finally, when done, let's just log the subviews
    // you would do whatever you would want here

    if (gesture.state == UIGestureRecognizerStateEnded)
    {
        // assuming the tags are numbers between 0 and 9 (inclusive), we can build the password here

        NSMutableString *password = [NSMutableString string];

        for (UIView *subview in gesturedSubviews)
            [password appendFormat:@"%c", subview.tag + 48];

        NSLog(@"Password = %@", password);

        // clean up our array of gesturedSubviews

        gesturedSubviews = nil;

        // clean up the drawing of the path on the screen the user drew

        [shapeLayer removeFromSuperlayer];
        shapeLayer = nil;
        path = nil;
    }
}

产生类似的东西:

user path with lines

您有各种各样的选择,但希望您现在拥有构建基块,以便设计自己的解决方案。

答案 1 :(得分:0)

原谅我Rob,这里的纯抄袭:)在swift 3.0中需要相同的代码:)所以我把你写的这个很棒的小例子翻译成swift 3.0。

gene_neg = best100_gene[which("Data_PCA$ind$coord[, 2]" < 0, )]

更新:几乎就是这样;我也尝试翻译更新,但是我的翻译错过了一些内容并且没有用,所以我搜索了SO并制作了一个类似的,如果稍微不同的最终解决方案。

ViewController.swift

import UIKit

class ViewController: UIViewController {

static let kMargin:CGFloat = 10.0;

override func viewDidLoad()
{
super.viewDidLoad()

// create a container view that all of our subviews for which we want to detect touches are:

let containerWidth = fmin(self.view.bounds.size.width, self.view.bounds.size.height) - ViewController.kMargin * 2.0

let container = UIView(frame: CGRect(x: ViewController.kMargin, y: ViewController.kMargin, width: containerWidth, height: containerWidth))
container.backgroundColor = UIColor.darkGray
    view.addSubview(container)

// now create all of the subviews, specifying a tag for each; and

let cellWidth = (containerWidth - (4.0 * ViewController.kMargin)) / 3.0

    for column in 0 ..< 3 {
        for row in 0 ..< 3 {
            let cell = UIView(frame: CGRect(x: ViewController.kMargin + CGFloat(column) * (cellWidth + ViewController.kMargin), y: ViewController.kMargin + CGFloat(row) * (cellWidth + ViewController.kMargin), width: cellWidth, height: cellWidth))
            cell.tag = row * 3 + column;
            container.addSubview(cell)
        }
    }

// finally, create the gesture recognizer

    let pan = UIPanGestureRecognizer(target: self, action: #selector(handlePan))
    container.addGestureRecognizer(pan)
}


func handlePan(gesture: UIPanGestureRecognizer)
{
    var  gesturedSubviews : [UIView] = []

// if we're starting a gesture, initialize our list of subviews that we've gone over

if (gesture.state == .began)
{
    gesturedSubviews.removeAll()
}

    let location = gesture.location(in: gesture.view)
    for subview in (gesture.view?.subviews)! {
        if (subview.frame.contains(location)) {
            if (subview != gesturedSubviews.last) {
            gesturedSubviews.append(subview)
                subview.backgroundColor = UIColor.blue
        }
    }

// finally, when done, let's just log the subviews
// you would do whatever you would want here

if (gesture.state != .recognized)
{
print("We went over:");

for subview in gesturedSubviews {
            print(" %d", (subview as AnyObject).tag);
}

// you might as well clean up your static variable when you're done

}
}
}

}