iOS之UIButton扩大按钮的响应区域

在开发中有时会遇见设计图里按钮设计的特别小，这时会用到手动扩大uibutton的响应范围，下面有两个解决办法：

 

第一种方法：创建一个类目：uibutton+enlargetoucharea 

.h文件

#import <uikit/uikit.h>
 
@interface uibutton (enlargetoucharea)
 
- (void)setenlargeedgewithtop:(cgfloat) top right:(cgfloat) right bottom:(cgfloat) bottom left:(cgfloat) left;
 
- (void)setenlargeedge:(cgfloat) size;
 
@end

.m文件

 

//
//  uibutton+enlargetoucharea.m
//  hebeifm
//
//  created by apple on 16/4/27.
//  copyright © 2016年 apple. all rights reserved.
//
 
#import "uibutton+enlargetoucharea.h"
#import <objc/runtime.h>
 
@implementation uibutton (enlargetoucharea)
 
static char topnamekey;
static char rightnamekey;
static char bottomnamekey;
static char leftnamekey;
 
- (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);
}
 
- (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

使用方法：

    uibutton *button = [uibutton new];
    [button setenlargeedge:20];
    //或者
    [button setenlargeedgewithtop:20 right:20 bottom:20 left:20];

 

 

第二种：直接创建一个uibutton类，然后复写pointinside方法

使用时继承于此类即可

.h文件

#import <uikit/uikit.h>
 
@interface biggerclickareabutton : uibutton
 
@end

.m文件

#import "biggerclickareabutton.h"
 
@implementation biggerclickareabutton
 
- (bool)pointinside:(cgpoint)point withevent:(uievent*)event
{
    cgrect bounds = self.bounds;
    //若原热区小于44x44，则放大热区，否则保持原大小不变
    cgfloat widthdelta = max(44.0 - bounds.size.width, 0);
    cgfloat heightdelta = max(44.0 - bounds.size.height, 0);
    bounds = cgrectinset(bounds, -0.5 * widthdelta, -0.5 * heightdelta);
    return cgrectcontainspoint(bounds, point);
}
 
 
@end

使用时直接继承创建即可