18

我有一个自定义的 UISlider，由于“拇指图像”的大小，大手指的人很难抓住和滑动。有没有办法在不改变图像大小的情况下增加可点击/可拖动区域的大小？

如果有帮助，这是我用于创建自定义滑块的代码：

[slider setMaximumTrackImage:[[UIImage imageNamed:@"max.png"]
                                             resizableImageWithCapInsets:UIEdgeInsetsMake(0, 20, 0, 20)]
                                   forState:UIControlStateNormal];
[slider setMinimumTrackImage:[[UIImage imageNamed:@"min.png"]
                                             resizableImageWithCapInsets:UIEdgeInsetsMake(0, 20, 0, 20)]
                                   forState:UIControlStateNormal];
[slider setThumbImage:[UIImage imageNamed:@"thumb.png"]
                            forState:UIControlStateNormal];
4

6 回答 6

27

我最终继承了 UISlider 并覆盖了这个方法：

- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent*)event {
    CGRect bounds = self.bounds;
    bounds = CGRectInset(bounds, -10, -15);
    return CGRectContainsPoint(bounds, point);
}

这将可触摸区域的左侧和右侧扩展了 10 个像素，顶部和底部扩展了 15 个像素。

于 2012-11-15T20:10:36.743 回答
7

此解决方案适用于 iOS 8：

class ExtUISlider: UISlider {

    var thumbTouchSize : CGSize = CGSizeMake(50, 50)

    override func pointInside(point: CGPoint, withEvent event: UIEvent?) -> Bool {
        let bounds = CGRectInset(self.bounds, -thumbTouchSize.width, -thumbTouchSize.height);
        return CGRectContainsPoint(bounds, point);
    }

    override func beginTrackingWithTouch(touch: UITouch, withEvent event: UIEvent) -> Bool {
        let thumbPercent = (value - minimumValue) / (maximumValue - minimumValue)
        let thumbSize = thumbImageForState(UIControlState.Normal)!.size.height
        let thumbPos = CGFloat(thumbSize) + (CGFloat(thumbPercent) * (CGFloat(bounds.size.width) - (2 * CGFloat(thumbSize))))
        let touchPoint = touch.locationInView(self)

        return (touchPoint.x >= (thumbPos - thumbTouchSize.width) &&
            touchPoint.x <= (thumbPos + thumbTouchSize.width))
    }
}

学分转到这篇文章：http ://www.mpatric.com/2009-04-15-more-responsive-sliders-on-the-iphone

于 2014-10-11T15:44:37.277 回答
7

斯威夫特 3

UISlider触摸面积增加的子类

class CustomSlider: UISlider {

    private var thumbTouchSize = CGSize(width: 40, height: 40)

    override func point(inside point: CGPoint, with event: UIEvent?) -> Bool {
        let increasedBounds = bounds.insetBy(dx: -thumbTouchSize.width, dy: -thumbTouchSize.height)
        let containsPoint = increasedBounds.contains(point)
        return containsPoint
    }

    override func beginTracking(_ touch: UITouch, with event: UIEvent?) -> Bool {
        let percentage = CGFloat((value - minimumValue) / (maximumValue - minimumValue))
        let thumbSizeHeight = thumbRect(forBounds: bounds, trackRect:trackRect(forBounds: bounds), value:0).size.height
        let thumbPosition = thumbSizeHeight + (percentage * (bounds.size.width - (2 * thumbSizeHeight)))
        let touchLocation = touch.location(in: self)
        return touchLocation.x <= (thumbPosition + thumbTouchSize.width) && touchLocation.x >= (thumbPosition - thumbTouchSize.width)
    }
}
于 2017-01-20T20:16:23.090 回答
3

我最终使用了它，它对我来说效果很好。

发布此答案，以便对某人有所帮助。

import UIKit

class CustomSlider: UISlider {

/*
// Only override draw() if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
override func draw(_ rect: CGRect) {
    // Drawing code
}
*/
// Increase slider height
   override func trackRect(forBounds bounds: CGRect) -> CGRect {
    let customBounds: CGRect = CGRect(origin: bounds.origin, size: CGSize(width: bounds.size.width, height: 5.0))
    return customBounds
}



override func thumbRect(forBounds bounds: CGRect, trackRect rect: CGRect, value: Float) -> CGRect {
    return super.thumbRect(
        forBounds: bounds, trackRect: rect, value: value)


}

// Increase Thumb hot spot clickable area
override func point(inside point: CGPoint, with event: UIEvent?) -> Bool {
    var bounds: CGRect = self.bounds
    bounds = bounds.insetBy(dx: -10, dy: -10);
    return bounds.contains(point);

}

override func awakeFromNib() {
    // Configure Volume slider
    let thumbImageNormal = UIImage.init(named:"thumb")
    self.setThumbImage(thumbImageNormal, for: .normal)

    super.awakeFromNib()
}

}
于 2016-09-09T12:45:32.897 回答
1

您也可以只增加图像大小，这将导致滑块拇指大小的增加。

  1. 如果您需要保持图像尺寸不太大但调整滑块大小，只需在图像内容周围添加透明空间。 在此处输入图像描述

  2. 如果您在 UITableViewCell 中使用滑块，问题也在于滑块之前的表格视图处理手势。要更改这一点，请使用以下解决方案： https ://stackoverflow.com/a/37751635/2150954 我认为将他的代码翻译成 Objective C 并不太难。

于 2016-11-22T08:23:46.800 回答
-1

调整框架大小并将图像对齐更改为所需的。您可以使其对齐居中、左、右、上或下。这样做：

CGRect newFrame = sliderHandle.frame;
CGRectSetWidth(newFrame, 80);
CGRectSetHeight(newFrame, 80);
[sliderHandle setFrame:newFrame];
[sliderHandle setContentMode:UIViewContentModeCenter];

所以你的触摸框会更大，图像比例将保持不变。

于 2012-11-07T13:38:54.990 回答