对于仿照新闻首页的页面，已经有比较好用的OC版本，现在我们来写一个swift版本的。
设备：xcode 10.2 语言：swift 4.2
效果图：
我们先创建一个多控制器的导航栏，直接上代码：
- //
- // JHSBarItemView.swift
- // ScrollBarController
- //
- // Created by yaojinhai on 2019/4/15.
- // Copyright © 2019年 yaojinhai. All rights reserved.
- //
- import UIKit
- enum BarItemBorderType {
- case defualt
- case barItem
- case maskView
- case customItem
- }
- protocol JHSBarItemViewDelegate: NSObjectProtocol {
- func selectedIndexItem(view: JHSBarItemView,index: Int) -> Void
- }
- class JHSBarItemView: UIView {
- var minMargin: CGFloat = BarConfig.minMargin;
- weak var delegate: JHSBarItemViewDelegate?
- var lineBarView: UIView!
- var barType = BarItemBorderType.defualt {
- didSet{
- configBarType();
- removeBarItem(idx: selectedIndex);
- }
- }
- var selectedIndex = 0;
- var titles: [String]!{
- didSet{
- caculateItemSize();
- }
- }
- private var titlesView: UICollectionView!
- private var cachesSize = [String:CGSize]();
- override init(frame: CGRect) {
- super.init(frame: frame);
- createContentView();
- }
- convenience init(frame: CGRect,titles: [String]) {
- self.init(frame: frame);
- self.titles = titles;
- createContentView();
- caculateItemSize();
- }
- func progressWidth() -> Void {
- }
- required init?(coder aDecoder: NSCoder) {
- fatalError("init(coder:) has not been implemented")
- }
- }
- extension JHSBarItemView: UICollectionViewDataSource,UICollectionViewDelegateFlowLayout {
- private func caculateItemSize() -> Void {
- guard let itemTitles = titles ,itemTitles.count > 0 else {
- return;
- }
- var maxWidth: CGFloat = 0;
- for item in itemTitles {
- let size = item.textSize(size: CGSize(width: width, height: height), font: BarConfig.normalFont);
- cachesSize[item] = CGSize(width: size.width, height: height);
- maxWidth += size.width;
- }
- let gap = (width - maxWidth) / CGFloat(itemTitles.count + 1);
- minMargin = max(gap, BarConfig.minMargin);
- titlesView.reloadData();
- removeBarItem(idx: selectedIndex);
- }
- private func createContentView() -> Void {
- if titlesView != nil {
- return;
- }
- let layout = UICollectionViewFlowLayout();
- layout.minimumLineSpacing = 0;
- layout.minimumInteritemSpacing = 0;
- layout.scrollDirection = .horizontal;
- titlesView = FMBaseCollectionView(frame: .init(x: 0, y: 0, width: width, height: height), collectionViewLayout: layout);
- addSubview(titlesView);
- titlesView.register(BarItemViewCell.self, forCellWithReuseIdentifier: "title");
- titlesView.delegate = self;
- titlesView.dataSource = self;
- let lineView = createView(rect: .init(x: 0, y: height - 1, width: width, height: 1));
- lineView.backgroundColor = rgbColor(rgb: 234);
- }
- // MARK: - collection view delegate and dataSource
- func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
- return titles?.count ?? 0;
- }
- func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
- return UIEdgeInsets(top: 0, left: minMargin, bottom: 0, right: minMargin);
- }
- func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
- if titles == nil {
- return CGSize.zero;
- }
- let item = titles[indexPath.row];
- if let size = cachesSize[item] {
- return CGSize(width: size.width + minMargin, height: height);
- }
- let size = titles[indexPath.row].textSize(size: CGSize.init(width: width, height: height), font: BarConfig.normalFont);
- let newSize = CGSize(width: size.width + minMargin, height: height);
- cachesSize[item] = size;
- return newSize;
- }
- func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
- let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "title", for: indexPath) as! BarItemViewCell;
- cell.titleLabel.text = titles[indexPath.row];
- cell.titleLabel.isHighlighted = selectedIndex == indexPath.row;
- return cell;
- }
- func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
- didSelected(idx: indexPath.row);
- delegate?.selectedIndexItem(view: self, index: indexPath.row);
- }
- func didSelected(idx: Int) -> Void {
- let indexPath = IndexPath(item: idx, section: 0);
- titlesView.scrollToItem(at: indexPath, at: .centeredHorizontally, animated: true);
- let cell = titlesView.cellForItem(at: indexPath) as? BarItemViewCell;
- cell?.titleLabel.isHighlighted = true;
- cell?.RunAnimation();
- removeBarItem(idx: indexPath.row);
- if selectedIndex != indexPath.row {
- let preCell = titlesView.cellForItem(at: .init(row: selectedIndex, section: 0)) as? BarItemViewCell;
- preCell?.titleLabel.isHighlighted = false;
- preCell?.RunAnimation();
- selectedIndex = indexPath.row;
- }
- }
- }
- extension JHSBarItemView {
- private func removeBarItem(idx: Int) {
- if barType == .barItem {
- let size = getMaxWidthAt(index: idx);
- lineBarView.frame = .init(x: size.width, y: height - 2, width: size.height, height: 2);
- }else if barType == .maskView {
- let size = getMaxWidthAt(index: idx);
- lineBarView.frame = .init(x: size.width - minMargin/2, y: 0, width: size.height + minMargin, height: height);
- }
- }
- func getMaxWidthAt(index: Int) -> CGSize {
- if titles == nil || titles.count == 0 {
- return CGSize.zero;
- }
- var maxWidth: CGFloat = minMargin;
- var sizeWidth: CGFloat = cachesSize[titles[0]]!.width;
- if index > 0 {
- for item in 1...index {
- let title = titles[item];
- let size = cachesSize[title]!;
- maxWidth += size.width + minMargin;
- sizeWidth = size.width;
- }
- }
- return CGSize(width: maxWidth + minMargin/2, height: sizeWidth);
- }
- private func configBarType() -> Void {
- if barType == .barItem {
- if lineBarView == nil {
- lineBarView = createView(rect: .init(x: 0, y: height - 2, width: 30, height: 2));
- lineBarView.backgroundColor = UIColor.red;
- lineBarView.layer.cornerRadius = 2;
- lineBarView.layer.masksToBounds = true;
- }
- titlesView.addSubview(lineBarView);
- }else if barType == .maskView {
- if lineBarView == nil {
- lineBarView = createView(rect: .init(x: 0, y: 0, width: 30, height: height));
- lineBarView.backgroundColor = UIColor.green.withAlphaComponent(0.2);
- lineBarView.isUserInteractionEnabled = false;
- }
- titlesView.addSubview(lineBarView);
- }else{
- titlesView?.removeFromSuperview();
- }
- }
- }
- class BarItemViewCell: UICollectionViewCell {
- var titleLabel: UILabel!
- override init(frame: CGRect) {
- super.init(frame: frame);
- titleLabel = createLabel(rect: bounds, text: "");
- titleLabel.textAlignment = .center;
- titleLabel.textColor = BarConfig.normalColor;
- titleLabel.highlightedTextColor = BarConfig.hlightedColor;
- titleLabel.font = BarConfig.normalFont;
- }
- required init?(coder aDecoder: NSCoder) {
- fatalError("init(coder:) has not been implemented")
- }
- func RunAnimation(animation: Bool = true) -> Void {
- self.titleLabel.font = self.titleLabel.isHighlighted ? BarConfig.hlightedFont : BarConfig.normalFont;
- }
- }
这个封装了导航栏的操作，并且实现了自动刷新功能。我们也可以自己扩展实现。
我们来定义一个控制器：
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//// JHSBarController.swift// ScrollBarController//// Created by yaojinhai on 2019/4/15.// Copyright © 2019年 yaojinhai. All rights reserved.// import UIKit protocol JHSBarControllerDelegate: NSObjectProtocol { func barControllerAt(controller: JHSBarController, index: Int) -> UIViewController; func barControllerForTitle(controller: JHSBarController,index: Int) -> String? func numberOfController(controller: JHSBarController) -> Int} class JHSBarController: JHSBaseViewController { private var topBarView: JHSBarItemView! private var cachesController = [Int:UIViewController](); private var cachesTitles = [Int:String](); private var countOfContrller = 0; weak var delegate: JHSBarControllerDelegate? var currentViewController: UIViewController{ return getControllerAt(idx: selectedIndex); } var selectedIndex: Int { get { let offSet = contentScrollView.contentOffset; let index = Int((offSet.x + 10)/width()); let idx = max(0, min(index, countOfContrller - 1)); return idx; } set{ let idx = max(0, min(newValue, countOfContrller - 1)); toScrollAtIndex(atIndx: idx); } } override func viewDidLoad() { super.viewDidLoad() topBarView = JHSBarItemView(frame: .init(x: 0, y: 64, width: width(), height: 40), titles: ["音乐","视频","旅游","新闻"]); topBarView.delegate = self; topBarView.barType = .maskView; addView(tempView: topBarView); configContentView(); } func reloadData() -> Void { cachesController.removeAll(); cachesTitles.removeAll(); countOfContrller = delegate?.numberOfController(controller: self) ?? 0; setBarTitles(); contentScrollView.setContentOffset(.init(x: selectedIndex.cgFloat * width(), y:0), animated: false); contentScrollView.contentSize = .init(width: countOfContrller.cgFloat * width(), height: 0); addSubController(); } private func setBarTitles() -> Void { var titles = [String](); for idx in 0..<countOfContrller { let tempTitme = delegate?.barControllerForTitle(controller: self, index: idx); cachesTitles[idx] = tempTitme ?? ""; titles.append(tempTitme ?? ""); } topBarView.titles = titles; } func isInScreen(rect: CGRect) -> Bool { let offset = contentScrollView.contentOffset; let bounds = contentScrollView.convert(.init(x: offset.x, y: offset.y, width: width(), height: contentScrollView.height), to: self.view); return bounds.intersects(rect); } private func toScrollAtIndex(atIndx: Int) -> Void { let isRight = atIndx < selectedIndex; let currentCtr = currentViewController; let currentRect = currentViewController.view.frame; currentCtr.view.frame.origin.x = atIndx.cgFloat * width(); contentScrollView.contentOffset = .init(x: atIndx.cgFloat * width(), y: 0); let atCtroller = getControllerAt(idx: atIndx); let orginRect = atCtroller.view.frame; atCtroller.view.frame.origin.x += isRight ? -width() : width(); contentScrollView.bringSubviewToFront(currentCtr.view); UIView.animate(withDuration: 0.3, animations: { currentCtr.view.frame.origin.x += isRight ? self.width() : -self.width(); atCtroller.view.frame = orginRect; }) { (finshed) in currentCtr.view.frame = currentRect; } } private func addSubController() -> Void { let start = max(selectedIndex - 1, 0); let end = max(min(selectedIndex + 1, countOfContrller - 1), 0); for idx in start...end { _ = getControllerAt(idx: idx); } } private func getControllerAt(idx: Int) -> UIViewController { var controller = cachesController[idx]; if controller == nil { controller = delegate?.barControllerAt(controller: self, index: idx); cachesController[idx] = controller; } let rect = CGRect(x: idx.cgFloat * width(), y: 0, width: width(), height: contentScrollView.height); controller?.view.frame = rect; if controller!.view.superview == nil { contentScrollView.addSubview(controller!.view); } if controller!.parent == nil { addChild(controller!); } if let scrollView = controller?.view as? UIScrollView { scrollView.contentOffset.y = 0; } if let subViews = controller?.view.subviews { for item in subViews { guard let scroll = item as? UIScrollView else{ continue; } scroll.contentOffset.y = 0; } } return controller!; } func configContentView() -> Void { setContentScrollView(rect: CGRect.init(x: 0, y: topBarView.maxY, width: width(), height: height() - topBarView.height)); contentScrollView.delegate = self; contentScrollView.isPagingEnabled = true; } func scrollViewDidScroll(_ scrollView: UIScrollView) { addSubController(); } func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) { for item in children { if !isInScreen(rect: item.view.frame) { item.removeFromParent(); item.view.removeFromSuperview(); } } addSubController(); topBarView.didSelected(idx: selectedIndex); } func scrollViewDidEndScrollingAnimation(_ scrollView: UIScrollView) { scrollViewDidEndDecelerating(scrollView); } func scrollViewDidEndDragging(_ scrollView: UIScrollView, willDecelerate decelerate: Bool) { if !decelerate { scrollViewDidEndDecelerating(scrollView); } } } extension JHSBarController: JHSBarItemViewDelegate{ func selectedIndexItem(view: JHSBarItemView, index: Int) { selectedIndex = index; }} |
我们只要继承这个就可以了：下面我们看使用方法：
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//// MainViewController.swift// ScrollBarController//// Created by yaojinhai on 2019/4/15.// Copyright © 2019年 yaojinhai. All rights reserved.// import UIKit class MainViewController: JHSBarController { override func viewDidLoad() { super.viewDidLoad() delegate = self; reloadData(); } } extension JHSBarController: JHSBarControllerDelegate { func barControllerAt(controller: JHSBarController, index: Int) -> UIViewController { let ctrl = DetialViewController() ctrl.index = index; return ctrl; } func barControllerForTitle(controller: JHSBarController, index: Int) -> String? { return "第(index)个页面"; } func numberOfController(controller: JHSBarController) -> Int { return 5; } } |
最后付上demo地址
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持服务器之家。
原文链接：https://blog.csdn.net/yaojinhai06/article/details/89333005
