如何修改UIButton響應區域
修改UIButton響應區域,以前處理這個需求時,是建一個view,添加手勢,覆蓋在需響應的區域,這種方法比較low, 可以通過新建一個分類,利用runtime來實現。
- 新建一個UIView,覆蓋在需響應的熱區
- 新建分類,利用runtime來實現
下面介紹新建分類的方法來實現熱區響應擴大
.h
定義調用方法, 調用時只需設置需響應熱區的上、右、下、左的值,兩個不同的方法供不同場景調用:
@interface UIButton (Extension)
//分別設置不同的值
- (void)setEnlargeEdgeWithTop:(CGFloat) top right:(CGFloat) right bottom:(CGFloat) bottom left:(CGFloat) left;
//設置同一個值
- (void)setEnlargeEdge:(CGFloat) size;
@end
.m
#import "UIButton+Extension.h"
#import <objc/runtime.h> //一定要導入
@implementation UIButton (Extension)
static char topNameKey;
static char rightNameKey;
static char bottomNameKey;
static char leftNameKey;
//設置統一的值,上、右、下、左爲同一值
- (void)setEnlargeEdge:(CGFloat) size
{
objc_setAssociatedObject(self, &topNameKey, [NSNumber numberWithFloat:size], OBJC_ASSOCIATION_COPY_NONATOMIC);
objc_setAssociatedObject(self, &rightNameKey, [NSNumber numberWithFloat:size], OBJC_ASSOCIATION_COPY_NONATOMIC);
objc_setAssociatedObject(self, &bottomNameKey, [NSNumber numberWithFloat:size], OBJC_ASSOCIATION_COPY_NONATOMIC);
objc_setAssociatedObject(self, &leftNameKey, [NSNumber numberWithFloat:size], OBJC_ASSOCIATION_COPY_NONATOMIC);
}
//設置熱區,可以單獨設置上、右、下、左的值
- (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);
}
//獲取屬性
- (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;
}
}
//重寫方法
- (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;
}