如何將3Dtouchforce添加到UIButton？

Question

我想在點擊或拖動按鈕時測量觸摸力。我創建了一個UITapGestureRecognizer（竊聽），並將其添加到myButton的是這樣的：

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

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

我創建了一個名爲方法buttonPrssed這樣的：

-(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); 

} 

我不斷收到零個值（0.0000）爲觸摸。任何幫助或建議，將不勝感激。我做了一個搜索，發現DFContinuousForceTouchGestureRecongnizer示例項目，但發現它太複雜了。我使用具有觸摸功能的iPhone 6 Plus。在屏幕上，但不使用該代碼的按鈕上任何其他地區攻絲時，我還可以測量觸摸：

- (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

你得到0.0000在buttonPressed，因爲用戶已經解除了他的手指時，這就是所謂的。

你說得對，你需要在touchesMoved方法中得到力，但是你需要在UIButton的touchesMoved方法中得到它。因此，你需要繼承的UIButton並覆蓋其touchesMoved方法：

頭文件

#import <UIKit/UIKit.h> 

@interface ForceButton : UIButton 

@end 

實現：

#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 

而且，也沒有必要使用UITapGestureRecognizer檢測單擊一個UIButton。改用addTarget。