简介：
以前UITabbar使用中间有一个凸起按钮时，常常就需要用到hitTest来处理可点击的范围。 示例代码：
- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
UIView *hitView = nil;
//NSLog(@"point:%@", NSStringFromCGPoint(point));
UIButton *roundBtn = (UIButton *)[self viewWithTag:];
UIButton *leftBtn = (UIButton *)[self viewWithTag:];
UIButton *rightBtn = (UIButton *)[self viewWithTag:];
BOOL pointInRound = [self touchPointInsideCircle:roundBtn.center radius: targetPoint:point];
if (pointInRound) {
hitView = roundBtn;
} else if(CGRectContainsPoint(leftBtn.frame, point)) {
hitView = leftBtn;
} else if(CGRectContainsPoint(rightBtn.frame, point)) {
hitView = rightBtn;
} else {
hitView = self;
}
return hitView;
}
增加categ，可以拓展按钮的点击范围：
#import <UIKit/UIKit.h> @interface UIButton (EnlargeTouchArea) /**
* 扩大 UIButton 的點擊範圍
* 控制上下左右的延長範圍
*
* @param top <#top description#>
* @param right <#right description#>
* @param bottom <#bottom description#>
* @param left <#left description#>
*/
- (void)setEnlargeEdgeWithTop:(CGFloat)top right:(CGFloat)right bottom:(CGFloat)bottom left:(CGFloat)left; @end
#import "UIButton+Category.h"
#import <objc/runtime.h>
@implementation UIButton (EnlargeTouchArea) static char topNameKey;
static char rightNameKey;
static char bottomNameKey;
static char leftNameKey; - (void)setEnlargeEdgeWithTop:(CGFloat)top right:(CGFloat)right bottom:(CGFloat)bottom left:(CGFloat)left
{
objc_setAssociatedObject(self, &topNameKey, [NSNumber numberWithFloat:top], OBJC_ASSOCIATION_COPY_NONATOMIC);
objc_setAssociatedObject(self, &rightNameKey, [NSNumber numberWithFloat:right], OBJC_ASSOCIATION_COPY_NONATOMIC);
objc_setAssociatedObject(self, &bottomNameKey, [NSNumber numberWithFloat:bottom], OBJC_ASSOCIATION_COPY_NONATOMIC);
objc_setAssociatedObject(self, &leftNameKey, [NSNumber numberWithFloat:left], OBJC_ASSOCIATION_COPY_NONATOMIC);
} - (CGRect)enlargedRect
{
NSNumber *topEdge = objc_getAssociatedObject(self, &topNameKey);
NSNumber *rightEdge = objc_getAssociatedObject(self, &rightNameKey);
NSNumber *bottomEdge = objc_getAssociatedObject(self, &bottomNameKey);
NSNumber *leftEdge = objc_getAssociatedObject(self, &leftNameKey);
if (topEdge && rightEdge && bottomEdge && leftEdge) {
return CGRectMake(self.bounds.origin.x - leftEdge.floatValue,
self.bounds.origin.y - topEdge.floatValue,
self.bounds.size.width + leftEdge.floatValue + rightEdge.floatValue,
self.bounds.size.height + topEdge.floatValue + bottomEdge.floatValue);
}
else
{
return self.bounds;
}
} - (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
CGRect rect = [self enlargedRect];
if (CGRectEqualToRect(rect, self.bounds)) {
return [super hitTest:point withEvent:event];
}
return CGRectContainsPoint(rect, point) ? self : nil;
} @end
另一种实现方式：扩大按钮的点击区域
要扩大UIButton的点击事件响应范围，只需要重写UIButton的hitTest方法
//将点击事件响应范围扩大到周边20个点
- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
CGRect rect = self.frame; //新的响应事件的区域
//这里的区域是在父控件坐标系内的
rect.origin.x -= ;
rect.origin.y -= ;
rect.size.height += * ;
rect.size.width += * ; //将点转换到与响应事件的区域在同一个坐标系内
CGPoint p = [self convertPoint:point toView:self.superview]; //判断点是否在新的事件响应区域内
if (CGRectContainsPoint(rect, p))
{
return self;
}
else
{
return [super hitTest:point withEvent:event];
}
}