Question

我创建了一个视图项目并添加了一个collectionView。我注册了UICollectionReusableView的简单子类

final class TestReusableView: UICollectionReusableView {
  override init(frame: CGRect) {
    super.init(frame: frame)
    backgroundColor = UIColor.red
  }
  ...
}

设置数据源并委托给自己

extension ViewController: UICollectionViewDataSource {
  func numberOfSections(in collectionView: UICollectionView) -> Int {
    return 1
  }

  func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    return 100
  }

  func collectionView(_ collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, at indexPath: IndexPath) -> UICollectionReusableView {
    let headerView = collectionView.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier: kHeader, for: indexPath)
    return headerView
  }

  func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath)
    cell.backgroundColor = UIColor.blue
    return cell
  }
}

extension ViewController: UICollectionViewDelegateFlowLayout {
  func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, referenceSizeForHeaderInSection section: Int) -> CGSize {
    return CGSize(width: collectionView.bounds.width, height: 88)
  }
}

结果是节标题似乎位于垂直滚动指示符的上方。但是，如果我针对10.3.1模拟器运行应用程序，行为就像我期望的那样。

Answer 1

这对我有用：

- (void)collectionView:(UICollectionView *)collectionView willDisplaySupplementaryView:(UICollectionReusableView *)view forElementKind:(NSString *)elementKind atIndexPath:(NSIndexPath *)indexPath {
    if (SystemVersionGraterOrEqual(11)) {
        if ([elementKind isEqualToString:UICollectionElementKindSectionHeader]) {
            view.layer.zPosition = 0;
    }
}

}

Answer 2

我无法尝试，但您可以尝试将其添加到let flow = collectionView.collectionViewLayout as! UICollectionViewFlowLayout flow.sectionHeadersPinToVisibleBounds = true：

    /* eslint-disable jsx-a11y/img-has-alt,class-methods-use-this */
import React, { Component } from 'react';
import PropTypes from 'prop-types';
import todoStyle from 'src/style/todo-style.scss';
import { Router, Route, hashHistory as history } from 'react-router';
import Myaccount from 'src/components/myaccount.jsx';

export default class Headermenu extends Component {

  constructor(){
  super();

  // Initial state
  this.state = { open: false };

}

toggle() {
  this.setState({
    open: !this.state.open
  });
}

  componentdidMount() {
    this.menuclickevent = this.menuclickevent.bind(this);
    this.collapse = this.collapse.bind(this);
    this.myaccount = this.myaccount.bind(this);
    this.logout = this.logout.bind(this);
  }

  render() {
    return (
      <div>

        <div style={{ textAlign: 'center', marginTop: '10px' }} id="menudiv" onBlur={this.collapse}>
          <button onClick={this.toggle.bind(this)} > Menu </button>

          <div id="demo" className={"collapse" + (this.state.open ? ' in' : '')}>
            <label className="menu_items" onClick={this.myaccount}>MyAccount</label>
            <div onClick={this.logout}>
              Logout
            </div>
          </div>

        </div>
      </div>
    );
  }

  menuclickevent() {
    const listmenu = document.getElementById('listmenu');
    listmenu.style.display = 'block';
  }



  logout() {
    console.log('Logout');
  }
  myaccount() {
    history.push('/myaccount');
    window.location.reload();

  }


}

Answer 3

即使我在我的应用程序中遇到了同样的问题，也计划在2周内发布。我没有时间研究为什么这只是在iOS 11中失败。因此，我做的快速工作是用footerView替换headerView的用法，因为footerView没有这个问题。< / p>

iOS11 UICollectionSectionHeader剪辑滚动指示器

3 个答案: