erpsuiteios/common/UIScrollVIew+Empty/UIScrollView+Empty.m

//
//  UIScrollView+Empty.m
//  UIScrollViewEmpty
//
//  Created by Jack on 2018/9/5.
//  Copyright © 2018年 United Software Applications. All rights reserved.
//

#import "UIScrollView+Empty.h"
#import "RAEmptyDataView.h"
#import <objc/runtime.h>

static const char *emptyKey = "emptyKey";

static const float duration = 0.25;

@implementation UIScrollView (Empty)

- (void)setEmptyContentView:(RAEmptyDataView *)contentView {
    if (contentView) {
        UIView *view = objc_getAssociatedObject(self, emptyKey);
        if (view) {
            [view removeFromSuperview];
        }
        
        [self insertSubview:contentView atIndex:0];
        
        [self willChangeValueForKey:@"emptyView"];
        objc_setAssociatedObject(self, emptyKey, contentView, OBJC_ASSOCIATION_RETAIN);
        [self didChangeValueForKey:@"emptyView"];
    }
}

- (RAEmptyDataView *)emptyContentView {
    
    RAEmptyDataView *contentView = objc_getAssociatedObject(self, emptyKey);
    
    if (!contentView) {
        contentView = [RAEmptyDataView new];
        contentView.autoresizingMask = UIViewAutoresizingFlexibleWidth|UIViewAutoresizingFlexibleHeight;
        contentView.hidden = YES;
        
        [self setEmptyContentView:contentView];
    }
    
    return contentView;
}

- (void)setEmptyView:(UIView *)emptyView {
    [self emptyContentView].emptyView = emptyView;
}

- (UIView *)emptyView {
    return [self emptyContentView].emptyView;
}

- (void)showEmpty {
    UIView *view = [self emptyContentView];
//    view.alpha = 0.0f;
    view.hidden = NO;
    [self bringSubviewToFront:view];
//    [UIView animateWithDuration:duration animations:^{
//        view.alpha = 1.0f;
//    }];
}

- (void)hideEmpty {
    UIView *view = [self emptyContentView];
//    [UIView animateWithDuration:duration animations:^{
//        view.alpha = 0.0f;
//    } completion:^(BOOL finished) {
        view.hidden = YES;
//    }];
    [self sendSubviewToBack:view];
}

@end