UITextField添加点击高亮状态

一、继承自UITextfield自定义一个SSTouchTextField
代码如下：

#import "SSTouchTextField.h"@implementation SSTouchTextField#pragma mark - Private- (void)setBackgroundHighlighted:(BOOL)highlighted{    [UIView animateWithDuration:0.3f delay:0.f options:UIViewAnimationOptionCurveEaseInOut animations:^{        if (highlighted) {            [self setBackgroundColor:SS_LINE_COLOR];        } else {            [self setBackgroundColor:[UIColor clearColor]];        }    } completion:^(BOOL finished) {    }];}#pragma mark - Overwrite- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(nullable UIEvent *)event{    [super touchesBegan:touches withEvent:event];    [self setBackgroundHighlighted:YES];}- (void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(nullable UIEvent *)event{    [super touchesMoved:touches withEvent:event];}- (void)touchesEnded:(NSSet<UITouch *> *)touches withEvent:(nullable UIEvent *)event{    [super touchesEnded:touches withEvent:event];    [self setBackgroundHighlighted:NO];}- (void)touchesCancelled:(NSSet<UITouch *> *)touches withEvent:(nullable UIEvent *)event{    [super touchesCancelled:touches withEvent:event];    [self setBackgroundHighlighted:NO];}// 增大点击区域- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event{    CGPoint convertPoint = [self convertPoint:point toView:self.superview];    UIEdgeInsets edgeInset = UIEdgeInsetsMake(0, 100, 0, 100);    CGRect edgeFrame = CGRectMake(self.view_minX - edgeInset.left,                                  self.view_minY - edgeInset.top,                                  self.view_width + edgeInset.left + edgeInset.right,                                  self.view_height + edgeInset.top + edgeInset.bottom);    CGRect convertFrame = [self.superview convertRect:edgeFrame toView:self.superview];    if (CGRectContainsPoint(convertFrame, convertPoint)) {        return self;    }    return [super hitTest:point withEvent:event];}@end