我想在UICollectionView中进行多项选择，我有五个部分有不同的选择设置。
我想在第1节和第2节中进行单一选择
以及第0,3和4节中的多项选择
当我单击两次相同的项目时，它将取消选择该项目
但是，当我单击单个部分项目时，它将取消先前选择的项目并选择单击的项目。
我按照我在UITableView中成功完成的另一个答案，但我不知道如何在UICollectionView中完美地完成这项工作？
感谢。
var collectionView: UICollectionView!
var selectArray: [IndexPath] = []
func collectionViewSetting(){
collectionView.delegate = self
collectionView.dataSource = self
collectionView.alwaysBounceVertical = true
collectionView.backgroundColor = UIColor.lightGray
collectionView.allowsMultipleSelection = true
self.view.addSubview(collectionView)
}
func numberOfSections(in collectionView: UICollectionView) -> Int {
let count = 5
return count
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return 10
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let key = Array(conditionsDictionary.keys)[indexPath.section]
let array: [String] = conditionsDictionary[key]!
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! CollectionViewCell
cell.label.text = "12345"
return cell
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
let cell = collectionView.cellForItem(at: indexPath)
cell?.backgroundColor = UIColor.orange
selectArray.append(indexPath)
}
func collectionView(_ collectionView: UICollectionView, didDeselectItemAt indexPath: IndexPath) {
let cell = collectionView.cellForItem(at: indexPath)
cell?.backgroundColor = UIColor.clear
if let index = selectArray.index(of:indexPath) {
selectArray.remove(at: index)
}
}
print(selectArray)
答案 0 :(得分：3)
根据您的要求，我准备了一个正常运行的示例代码。
Swift 4
//
// ViewController.swift
// SOCollectionSelectionHandling
//
// Created by Test User on 05/02/18.
// Copyright © 2018. Ltd. All rights reserved.
//
import UIKit
class ViewController: UIViewController {
var collectionView: UICollectionView!
var selectArray : [IndexPath] = []
let sections = 5
let cell = "MyCell"
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
setUpCollectionViewAndSettings()
}
func setUpCollectionViewAndSettings() {
let layout = UICollectionViewFlowLayout()
layout.itemSize = CGSize.init(width: 50, height: 50)
collectionView = UICollectionView.init(frame: self.view.frame , collectionViewLayout: layout)
collectionView.register(UICollectionViewCell.self, forCellWithReuseIdentifier: cell)
collectionView.alwaysBounceVertical = true
collectionView.backgroundColor = UIColor.lightGray
collectionView.delegate = self
collectionView.dataSource = self
collectionView.allowsMultipleSelection = true
self.view.addSubview(collectionView)
}
}
//MARK: Collection View Delegate and DataSource Methods
extension ViewController : UICollectionViewDelegate , UICollectionViewDataSource {
//MARK: Collection Data Source
func numberOfSections(in collectionView: UICollectionView) -> Int {
return sections
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return 10
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: self.cell, for: indexPath)
if selectArray.count > 0 {
selectArray.forEach { (selectedIndex) in
if (selectedIndex.section == indexPath.section && selectedIndex.row == indexPath.row) { // Change Color of selected Index
if (selectedIndex.section == 0 || selectedIndex.section == 3 || selectedIndex.section == 4) {
DispatchQueue.main.async {
let cell = collectionView.cellForItem(at: selectedIndex)
cell?.backgroundColor = UIColor.orange
}
} else {
cell.backgroundColor = UIColor.yellow
}
}
else { //Set Default Color of Not Selected Index
if indexPath.section == 0 || indexPath.section == 3 || indexPath.section == 4 {
cell.backgroundColor = UIColor.blue
} else {
cell.backgroundColor = UIColor.red
}
}
}
} else {
if indexPath.section == 0 || indexPath.section == 3 || indexPath.section == 4 {
collectionView.allowsMultipleSelection = true
cell.backgroundColor = UIColor.blue
} else {
collectionView.allowsMultipleSelection = false
cell.backgroundColor = UIColor.red
}
}
return cell
}
//MARK: Collection Delegate for Selection and Deselection
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
let cell = collectionView.cellForItem(at: indexPath)
if indexPath.section == 0 || indexPath.section == 3 || indexPath.section == 4 {
self.handleMultipleSelection (collectionView: collectionView ,cell : cell! , indexPath : indexPath )
} else {
selectArray.removeAll()
collectionView.allowsMultipleSelection = false
cell?.backgroundColor = UIColor.yellow
selectArray.append(indexPath)
print(selectArray)
collectionView.reloadData()
}
}
func collectionView(_ collectionView: UICollectionView, didDeselectItemAt indexPath: IndexPath) {
let cell = collectionView.cellForItem(at: indexPath)
if indexPath.section == 0 || indexPath.section == 3 || indexPath.section == 4 {
self.handleMultipleDeSelection(collectionView: collectionView
, cell: cell!, indexPath: indexPath)
} else {
//Remove all selected record from array for Single Selection
selectArray.removeAll()
cell?.backgroundColor = UIColor.red
}
collectionView.reloadData()
}
//MARK: Multiple Selection Handle Method
func handleMultipleDeSelection(collectionView: UICollectionView
, cell: UICollectionViewCell, indexPath: IndexPath) {
// Remove Previous Selected Cell Record from Array at time of Section Switching
if selectArray.count > 0 {
selectArray.forEach({ (path) in
if (path.section == indexPath.section) {
if let index = selectArray.index(of : path) {
let cell = collectionView.cellForItem(at: path)
if path.section == 0 || path.section == 3 || path.section == 4 {
cell?.backgroundColor = UIColor.blue
} else {
cell?.backgroundColor = UIColor.red
}
selectArray.remove(at:index)
}
}
})
}
cell.backgroundColor = UIColor.blue
if let index = selectArray.index(of:indexPath) {
selectArray.remove(at: index)
print(selectArray)
}
else {
//Removing Unwanted Section from array
if selectArray.count > 0 {
selectArray.forEach({ (path) in
if (path.section == 1 || path.section == 2) {
if let index = selectArray.index(of: path) {
let cell = collectionView.cellForItem(at: path)
cell?.backgroundColor = UIColor.red
selectArray.remove(at:index)
}
}
})
}
//Adding Selected cell in Selection Array
selectArray.append(indexPath)
print(selectArray)
collectionView.reloadData()
}
}
func handleMultipleSelection (collectionView: UICollectionView ,cell : UICollectionViewCell , indexPath : IndexPath ) {
// Remove Previous Selected Cell Record from Array at time of Section Switching
if selectArray.count > 0 {
selectArray.forEach({ (path) in
if (path.section != indexPath.section) {
if let index = selectArray.index(of : path) {
let cell = collectionView.cellForItem(at: path)
if path.section == 0 || path.section == 3 || path.section == 4 {
cell?.backgroundColor = UIColor.blue
} else {
cell?.backgroundColor = UIColor.red
}
selectArray.remove(at:index)
}
}
})
}
collectionView.allowsMultipleSelection = true
cell.backgroundColor = UIColor.orange
if let index = selectArray.index(of:indexPath) {
selectArray.remove(at: index)
print(selectArray)
collectionView.reloadData()
} else {
//Removing Unwanted Section from array
if selectArray.count > 0 {
selectArray.forEach({ (path) in
if (path.section == 1 || path.section == 2) {
if let index = selectArray.index(of: path) {
let cell = collectionView.cellForItem(at: path)
cell?.backgroundColor = UIColor.red
selectArray.remove(at:index)
}
}
})
}
//Adding Selected cell in Selection Array
selectArray.append(indexPath)
print(selectArray)
collectionView.reloadData()
}
}
}