iOS开发之功能模块--用runtime给UIView类别拓展PressMenu工具

这是个很有用的列别工具类，在聊天对话框添加和QQ一样的"复制、粘贴、取消"等选项，而且使用起来很方便，只要找到聊天泡泡内部的某个View，比如Label或者背景冒泡的UIImageView，直接add...即可实现下面的效果：

直接上源码：

UIView+PressMenu.h

 #import <UIKit/UIKit.h>

 @interface UIView (PressMenu)
 @property (strong, nonatomic) NSArray *menuTitles;
 @property (strong, nonatomic) UILongPressGestureRecognizer *pressGR;
 @property (copy, nonatomic) void(^menuClickedBlock)(NSInteger index, NSString *title);
 @property (strong, nonatomic) UIMenuController *menuVC;

 - (void)addPressMenuTitles:(NSArray *)menuTitles menuClickedBlock:(void(^)(NSInteger index, NSString *title))block;
 - (void)showMenuTitles:(NSArray *)menuTitles menuClickedBlock:(void(^)(NSInteger index, NSString *title))block;

 - (BOOL)isMenuVCVisible;
 - (void)removePressMenu;
 @end

UIView+PressMenu.m

 #import "UIView+PressMenu.h"
 #import <objc/runtime.h>

 @implementation UIView (PressMenu)

 static const NSString *kPressMenuSelectorPrefix = @"easePressMenuClicked_";
 static char PressMenuTitlesKey, PressMenuBlockKey, PressMenuGestureKey, MenuVCKey;

 #pragma mark M
 - (void)addPressMenuTitles:(NSArray *)menuTitles menuClickedBlock:(void(^)(NSInteger index, NSString *title))block{
     self.userInteractionEnabled = YES;
     self.menuClickedBlock = block;
     self.menuTitles = menuTitles;
     if (self.pressGR == nil) {
         self.pressGR = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(handlePress:)];
     }
     [self addGestureRecognizer:self.pressGR];
 }

 - (void)showMenuTitles:(NSArray *)menuTitles menuClickedBlock:(void(^)(NSInteger index, NSString *title))block{
     self.menuClickedBlock = block;
     self.menuTitles = menuTitles;
     [self p_showMenu];
 }

 - (BOOL)isMenuVCVisible{
     if (self.menuVC) {
         return [self.menuVC isMenuVisible];
     }
     return NO;
 }

 - (void)removePressMenu{
     if (self.menuVC) {
         [self.menuVC setMenuVisible:NO animated:YES];
         self.menuVC = nil;
     }
     if ([self.pressGR isKindOfClass:[UILongPressGestureRecognizer class]]) {
         [self removeGestureRecognizer:self.pressGR];
         self.pressGR = nil;
     }
     if (self.menuClickedBlock) {
         self.menuClickedBlock = nil;
     }
     if (self.menuTitles) {
         self.menuTitles = nil;
     }
 }

 #pragma mark SET_GET
 - (void)setMenuTitles:(NSArray *)menuTitles{
     objc_setAssociatedObject(self, &PressMenuTitlesKey, menuTitles, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
 }
 - (NSArray *)menuTitles{
     return objc_getAssociatedObject(self, &PressMenuTitlesKey);
 }

 - (void)setMenuClickedBlock:(void (^)(NSInteger, NSString *))menuClickedBlock{
     objc_setAssociatedObject(self, &PressMenuBlockKey, menuClickedBlock, OBJC_ASSOCIATION_COPY_NONATOMIC);
 }
 - (void (^)(NSInteger, NSString *))menuClickedBlock{
     return objc_getAssociatedObject(self, &PressMenuBlockKey);
 }

 - (void)setPressGR:(UILongPressGestureRecognizer *)pressGR{
     objc_setAssociatedObject(self, &PressMenuGestureKey, pressGR, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
 }
 - (UILongPressGestureRecognizer *)pressGR{
     return objc_getAssociatedObject(self, &PressMenuGestureKey);
 }

 - (void)setMenuVC:(UIMenuController *)menuVC{
     objc_setAssociatedObject(self, &MenuVCKey, menuVC, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
 }
 - (UIMenuController *)menuVC{
     return objc_getAssociatedObject(self, &MenuVCKey);
 }

 #pragma mark canPerformAction
 - (BOOL)canBecomeFirstResponder{
     if (self.menuClickedBlock) {
         return YES;
     }else{
         return [super canBecomeFirstResponder];
     }
 }

 -(BOOL)canPerformAction:(SEL)action withSender:(id)sender{
     if (self.menuClickedBlock) {
         for (int i=; i<self.menuTitles.count; i++) {
             if (action == NSSelectorFromString([NSString stringWithFormat:@"%@%d:", kPressMenuSelectorPrefix, i])) {
                 return YES;
             }
         }
         return NO;
     }else{
         return [super canPerformAction:action withSender:sender];
     }
 }

 -(void)handlePress:(UIGestureRecognizer*)recognizer{
     if (recognizer.state == UIGestureRecognizerStateBegan) {
         [self p_showMenu];
     }
 }

 - (void)p_showMenu{
     [self becomeFirstResponder];
     NSMutableArray *menuItems = [[NSMutableArray alloc] initWithCapacity:self.menuTitles.count];
     Class cls = [self class];
     SEL imp = @selector(pressMenuClicked:);
     for (int i=; i<self.menuTitles.count; i++) {
         NSString *title = [self.menuTitles objectAtIndex:i];
         //注册名添加方法sel，sel的具体实现在imp(pressMenuClicked:)
         SEL sel = sel_registerName([[NSString stringWithFormat:@"%@%d:", kPressMenuSelectorPrefix, i] UTF8String]);
         class_addMethod(cls, sel, [cls instanceMethodForSelector:imp], "v@");
         UIMenuItem *menuItem = [[UIMenuItem alloc] initWithTitle:title action:sel];
         [menuItems addObject:menuItem];
     }
     UIMenuController *menu = [UIMenuController sharedMenuController];
     [menu setMenuItems:menuItems];
     [menu setTargetRect:self.frame inView:self.superview];
     [menu setMenuVisible:YES animated:YES];
     self.menuVC = menu;
 }

 - (void)pressMenuClicked:(id)sender {
     NSString *selStr = NSStringFromSelector(_cmd);
     NSString *indexStr = [selStr substringFromIndex:kPressMenuSelectorPrefix.length];
     NSInteger index = indexStr.integerValue;
     if (index >= && index<self.menuTitles.count) {
         NSString *title = [self.menuTitles objectAtIndex:index];
         if (self.menuClickedBlock) {
             self.menuClickedBlock(index, title);
         }
     }
 }

 @end