Hippy/ios/sdk/component/headerrefresh/HippyHeaderRefresh.m

/*!
 * iOS SDK
 *
 * Tencent is pleased to support the open source community by making
 * Hippy available.
 *
 * Copyright (C) 2019 THL A29 Limited, a Tencent company.
 * All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#import "HippyHeaderRefresh.h"

@implementation HippyHeaderRefresh

- (void)setFrame:(CGRect)frame {
    CGRect properFrame = frame;
    if ([self superview]) {
        CGFloat width = CGRectGetWidth(frame);
        CGFloat height = CGRectGetHeight(frame);
        properFrame = CGRectMake(0, -height, width, height);
    }
    [super setFrame:properFrame];
}

- (void)scrollViewDidScroll {
    if (_scrollView) {
        if (self.onHeaderPulling && HippyRefreshStatusStartLoading != [self status] && HippyRefreshStatusFinishLoading != [self status]) {
            CGFloat offset = _scrollView.contentOffset.y;
            if (offset <= 0) {
                self.onHeaderPulling(@{ @"contentOffset": @(-offset) });
            }
        }
    }
    // Section cell will stick in wrong position while header is still refresh. in this scenario，the scrollview inset need to be reset.
    if ([self status] == HippyRefreshStatusFinishLoading || [self status] == HippyRefreshStatusStartLoading) {
        [self resetInset];
    }
}

- (void)resetInset
{
    CGFloat insetT = - self.scrollView.contentOffset.y > 0 ? - self.scrollView.contentOffset.y : 0;
    insetT = insetT > self.frame.size.height ? self.frame.size.height : insetT;

    if (self.scrollView.contentInset.top != insetT) {
        UIEdgeInsets inset = self.scrollView.contentInset;
        inset.top = insetT;
        self.scrollView.contentInset = inset;
    }
}

- (void)refresh {
    [UIView animateWithDuration:.2f animations:^{
        self.scrollView.contentOffset = CGPointMake(0, -self.bounds.size.height);
    } completion:^(BOOL finished) {
        self.status = HippyRefreshStatusStartLoading;
    }];
}

- (void)scrollViewDidEndDragging {
    if (_scrollView && -_scrollView.contentOffset.y > CGRectGetHeight(self.bounds)) {
        self.status = HippyRefreshStatusStartLoading;
    }
}

- (void)setStatus:(HippyRefreshStatus)status {
    if (_status == status) {
        return;
    }
    switch (status) {
        case HippyRefreshStatusIdle: {
            [UIView animateWithDuration:.2f animations:^{
                UIEdgeInsets insets = self.scrollView.contentInset;
                self.scrollView.contentInset = UIEdgeInsetsMake(0, insets.left, insets.bottom, insets.right);
            } completion:^(BOOL finished) {
            }];
        } break;
        case HippyRefreshStatusStartLoading: {
            CGFloat height = CGRectGetHeight(self.bounds);
            [UIView animateWithDuration:.2f animations:^{
                UIEdgeInsets insets = self.scrollView.contentInset;
                self.scrollView.contentInset = UIEdgeInsetsMake(height, insets.left, insets.bottom, insets.right);
            } completion:^(BOOL finished) {
                if (self.onHeaderReleased) {
                    CGFloat offset = self.scrollView.contentOffset.y;
                    self.onHeaderReleased(@{@"contentOffset": @(offset)});
                }
            }];
        } break;
        default:
            break;
    }
    _status = status;
    if ([_delegate respondsToSelector:@selector(refreshView:statusChanged:)]) {
        [_delegate refreshView:self statusChanged:_status];
    }
}

@end