新浪微博客户端(52)-长按或滑动显示表情

DJEmotionPageView.m

/*
         * 添加长按监听事件
         * 类似于android里面setOnLongClickListener
         */
        
        [self addGestureRecognizer:[[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(onLongClick:)]];

// 当触发长按事件时调用此方法
- (void)onLongClick:(UILongPressGestureRecognizer *)recognizer {

    /*
     * 获取长按事件状态,类似于android里面的 MotionEvent
     * android 里面的MotionEvent 同样有以下几种状态：
     * MotionEvent.ACTION_DOWN
     * MotionEvent.ACTION_MOVE
     * MotionEvent.ACTION_UP
     */
    switch (recognizer.state) {
        case UIGestureRecognizerStateBegan: // 事件开始
        case UIGestureRecognizerStateChanged:{
            /*
             * 获取触摸点的坐标，android里面对应的方法为
             * motionEvent.getX(), motionEvent.getY()
             */
            CGPoint touchPoint = [recognizer locationInView:recognizer.view];
            
            // 判断当前触摸点的坐标是否在某个表情按钮上，如果在则显示popView
             DJEmotionButton *btn = [self emotionButtonWithTouchPoint:touchPoint];
            if (btn) [self.popView showFromEmotionBtn:btn]; // 显示popView
        }
            break;
        case UIGestureRecognizerStateCancelled:
        case UIGestureRecognizerStateEnded:{ // 事件结束
            // 当事件结束时,判断当前触摸点的坐标是否在表情按钮上，如果在，则将对应表情按钮的内容输入到textVeiw
            [self.popView removeFromSuperview];
            CGPoint touchPoint = [recognizer locationInView:recognizer.view];
            DJEmotionButton *btn = [self emotionButtonWithTouchPoint:touchPoint];
            if (btn) [self sendBtnClickNotification:btn]; // 发送按钮点击通知
            
        }
            break;
        default:
            break;
    }

// 发送点击广播(和android类似,区别在于android的广播是只要有上下文对象context,就可以发送)
// iOS中的通知发送和接收都是通过NSNotificationCenter完成
- (void)sendBtnClickNotification:(DJEmotionButton *)btn {

    NSMutableDictionary *userInfo = [NSMutableDictionary dictionary];
    userInfo[DJEmotionDidSelctedEmotionKey] = btn.emotion;
    
    [[NSNotificationCenter defaultCenter] postNotificationName:DJEmotionDidSelectedNotification object:nil userInfo:userInfo];

}

/**
 * 点击表情监听方法
 * param btn 点击的表情按钮
 */
- (void)emotionBtnClick:(DJEmotionButton *)btn {
    
    [self.popView showFromEmotionBtn:btn];
    [self sendBtnClickNotification:btn];
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.15 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
        [self.popView removeFromSuperview];
    });

}

DJEmotionPopView.h

#import <UIKit/UIKit.h>

@class DJEmotion,DJEmotionButton;
@interface DJEmotionPopView : UIView

+ (instancetype)popView;
- (void)showFromEmotionBtn:(DJEmotionButton *)emotinBtn;


@property (nonatomic,strong) DJEmotion *emotion;


@end

DJEmotionPopView.m

// 在emotionBtn的位置显示popView
- (void)showFromEmotionBtn:(DJEmotionButton *)emotinBtn {

    // 获取当前应用程序最顶层的窗口
    UIWindow *lastWindow = [[UIApplication sharedApplication].windows lastObject];
    
    // 转换btn当前坐标系
    CGRect newFrame = [emotinBtn convertRect:emotinBtn.bounds toView:nil];
    
    self.centerX = CGRectGetMidX(newFrame);
    self.y = CGRectGetMaxY(newFrame) - self.height;
    
    // 将当前点击按钮的表情模型传递给popview
    self.emotion = emotinBtn.emotion;
    
    [lastWindow addSubview:self];

}

最终效果：