Question

我想在点击或拖动按钮时测量触摸力。我创建了一个UITapGestureRecognizer（用于点击）并将其添加到myButton，如下所示：

UITapGestureRecognizer *tapRecognizer2 = [[UITapGestureRecognizer      alloc] initWithTarget:self action:@selector(buttonPressed:)];

         [tapRecognizer2 setNumberOfTapsRequired:1];
        [tapRecognizer2 setDelegate:self];
        [myButton addGestureRecognizer:tapRecognizer2];

我创建了一个名为buttonPrssed的方法，如下所示：

-(void)buttonPressed:(id)sender 
{
    [myButton touchesMoved:touches withEvent:event];


   myButton = (UIButton *) sender;

    UITouch *touch=[[event touchesForView:myButton] anyObject];

    CGFloat force = touch.force;
    forceString= [[NSString alloc] initWithFormat:@"%f", force];
    NSLog(@"forceString in imagePressed is : %@", forceString);

}

我一直得到零值（0.0000）的触摸。任何帮助或建议将不胜感激。我做了一个搜索，发现了DFContinuousForceTouchGestureRecongnizer示例项目，但发现它太复杂了。我使用有触感的iPhone 6 Plus。我也可以在点击屏幕上的任何其他区域时测量触摸，但不能使用此代码测量按钮：

   - (void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
    [super touchesMoved:touches withEvent:event];

    UITouch *touch = [touches anyObject];

    //CGFloat maximumPossibleForce = touch.maximumPossibleForce;
    CGFloat force = touch.force;
    forceString= [[NSString alloc] initWithFormat:@"%f", force];
    NSLog(@"forceString is : %@", forceString);




}

Answer 1

您在0.0000中收到buttonPressed因为用户在调用此手指时已经抬起手指。

你是对的，你需要在touchesMoved方法中获得力量，但你需要在UIButton的touchesMoved方法中获得它。因此，您需要子类化UIButton并覆盖其touchesMoved方法：

标题文件：

#import <UIKit/UIKit.h>

@interface ForceButton : UIButton

@end

实现：

#import "ForceButton.h"

@implementation ForceButton

- (void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event {
    [super touchesMoved:touches withEvent:event];

    UITouch *touch = [touches anyObject];
    CGFloat force = touch.force;
    CGFloat relativeForce = touch.force / touch.maximumPossibleForce;

    NSLog(@"force: %f, relative force: %f", force, relativeForce);
}

@end

此外，您无需使用UITapGestureRecognizer来检测UIButton上的单击。只需使用addTarget代替。

如何将3dtouchforce添加到UIButton？

1 个答案: