[iphone] 빈 UITableView 처리. 친근한 메시지 인쇄

다음 라이브러리를 권장합니다. DZNEmptyDataSet

프로젝트에 추가하는 가장 쉬운 방법은 다음과 같이 Cocaopods와 함께 사용하는 것입니다. pod 'DZNEmptyDataSet'

TableViewController에서 다음 import 문 (Swift)을 추가합니다.

import DZNEmptyDataSet

그런 다음에 반드시 수업 부합 함을 선언하게 DNZEmptyDataSetSource하고 DZNEmptyDataSetDelegate그래서 같은를 :

class MyTableViewController: UITableViewController, DZNEmptyDataSetSource, DZNEmptyDataSetDelegate

귀하의에서 viewDidLoad다음 코드 줄을 추가합니다 :

tableView.emptyDataSetSource = self
tableView.emptyDataSetDelegate = self
tableView.tableFooterView = UIView()

이제 emptystate를 표시하기 위해해야 ​​할 일은 다음과 같습니다.

//Add title for empty dataset
func titleForEmptyDataSet(scrollView: UIScrollView!) -> NSAttributedString! {
    let str = "Welcome"
    let attrs = [NSFontAttributeName: UIFont.preferredFontForTextStyle(UIFontTextStyleHeadline)]
    return NSAttributedString(string: str, attributes: attrs)
}

//Add description/subtitle on empty dataset
func descriptionForEmptyDataSet(scrollView: UIScrollView!) -> NSAttributedString! {
    let str = "Tap the button below to add your first grokkleglob."
    let attrs = [NSFontAttributeName: UIFont.preferredFontForTextStyle(UIFontTextStyleBody)]
    return NSAttributedString(string: str, attributes: attrs)
}

//Add your image
func imageForEmptyDataSet(scrollView: UIScrollView!) -> UIImage! {
    return UIImage(named: "MYIMAGE")
}

//Add your button 
func buttonTitleForEmptyDataSet(scrollView: UIScrollView!, forState state: UIControlState) -> NSAttributedString! {
    let str = "Add Grokkleglob"
    let attrs = [NSFontAttributeName: UIFont.preferredFontForTextStyle(UIFontTextStyleCallout)]
    return NSAttributedString(string: str, attributes: attrs)
}

//Add action for button
func emptyDataSetDidTapButton(scrollView: UIScrollView!) {
    let ac = UIAlertController(title: "Button tapped!", message: nil, preferredStyle: .Alert)
    ac.addAction(UIAlertAction(title: "Hurray", style: .Default, handler: nil))
    presentViewController(ac, animated: true, completion: nil)
}

이 메소드는 필수가 아니며 버튼 등없이 빈 상태를 표시하는 것도 가능합니다.

Swift 4의 경우

// MARK: - Deal with the empty data set
// Add title for empty dataset
func title(forEmptyDataSet _: UIScrollView!) -> NSAttributedString! {
    let str = "Welcome"
    let attrs = [NSAttributedStringKey.font: UIFont.preferredFont(forTextStyle: UIFontTextStyle.headline)]
    return NSAttributedString(string: str, attributes: attrs)
}

// Add description/subtitle on empty dataset
func description(forEmptyDataSet _: UIScrollView!) -> NSAttributedString! {
    let str = "Tap the button below to add your first grokkleglob."
    let attrs = [NSAttributedStringKey.font: UIFont.preferredFont(forTextStyle: UIFontTextStyle.body)]
    return NSAttributedString(string: str, attributes: attrs)
}

// Add your image
func image(forEmptyDataSet _: UIScrollView!) -> UIImage! {
    return UIImage(named: "MYIMAGE")
}

// Add your button
func buttonTitle(forEmptyDataSet _: UIScrollView!, for _: UIControlState) -> NSAttributedString! {
    let str = "Add Grokkleglob"
    let attrs = [NSAttributedStringKey.font: UIFont.preferredFont(forTextStyle: UIFontTextStyle.callout), NSAttributedStringKey.foregroundColor: UIColor.white]
    return NSAttributedString(string: str, attributes: attrs)
}

// Add action for button
func emptyDataSetDidTapButton(_: UIScrollView!) {
    let ac = UIAlertController(title: "Button tapped!", message: nil, preferredStyle: .alert)
    ac.addAction(UIAlertAction(title: "Hurray", style: .default, handler: nil))
    present(ac, animated: true, completion: nil)
}

답변

-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    NSInteger actualNumberOfRows = <calculate the actual number of rows>;
    return (actualNumberOfRows  == 0) ? 1 : actualNumberOfRows;
}

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    NSInteger actualNumberOfRows = <calculate the actual number of rows>;
    if (actualNumberOfRows == 0) {
        // Produce a special cell with the "list is now empty" message
    }
    // Produce the correct cell the usual way
    ...
}

-(NSString*)tableView:(UITableView *)tableView titleForFooterInSection:(NSInteger)section   {

    NSString *message = @"";
    NSInteger numberOfRowsInSection = [self tableView:self.tableView numberOfRowsInSection:section ];

    if (numberOfRowsInSection == 0) {
        message = @"This list is now empty";
    }

    return message;
}

extension UITableView {
func setEmptyMessage(_ message: String) {
    guard self.numberOfRows() == 0 else {
        return
    }
    let messageLabel = UILabel(frame: CGRect(x: 0, y: 0, width: self.bounds.size.width, height: self.bounds.size.height))
    messageLabel.text = message
    messageLabel.textColor = .black
    messageLabel.numberOfLines = 0;
    messageLabel.textAlignment = .center;
    messageLabel.font = UIFont.systemFont(ofSize: 14.0, weight: UIFontWeightMedium)
    messageLabel.sizeToFit()

    self.backgroundView = messageLabel;
    self.separatorStyle = .none;
}

func restore() {
    self.backgroundView = nil
    self.separatorStyle = .singleLine
}

public func numberOfRows() -> Int {
    var section = 0
    var rowCount = 0
    while section < numberOfSections {
        rowCount += numberOfRows(inSection: section)
        section += 1
    }
    return rowCount
  }
}

extension UICollectionView {
func setEmptyMessage(_ message: String) {
    guard self.numberOfItems() == 0 else {
        return
    }

    let messageLabel = UILabel(frame: CGRect(x: 0, y: 0, width: self.bounds.size.width, height: self.bounds.size.height))
    messageLabel.text = message
    messageLabel.textColor = .black
    messageLabel.numberOfLines = 0;
    messageLabel.textAlignment = .center;
    messageLabel.font = UIFont.systemFont(ofSize: 18.0, weight: UIFontWeightSemibold)
    messageLabel.sizeToFit()
    self.backgroundView = messageLabel;
}

func restore() {
    self.backgroundView = nil
}

public func numberOfItems() -> Int {
    var section = 0
    var itemsCount = 0
    while section < self.numberOfSections {
        itemsCount += numberOfItems(inSection: section)
        section += 1
    }
    return itemsCount
  }
}

    protocol EmptyMessageViewType {
      mutating func setEmptyMessage(_ message: String)
      mutating func restore()
    }

    protocol ListViewType: EmptyMessageViewType where Self: UIView {
      var backgroundView: UIView? { get set }
    }

    extension UITableView: ListViewType {}
    extension UICollectionView: ListViewType {}

    extension ListViewType {
      mutating func setEmptyMessage(_ message: String) {
        let messageLabel = UILabel(frame: CGRect(x: 0,
                                                 y: 0,
                                                 width: self.bounds.size.width,
                                                 height: self.bounds.size.height))
        messageLabel.text = message
        messageLabel.textColor = .black
        messageLabel.numberOfLines = 0
        messageLabel.textAlignment = .center
        messageLabel.font = UIFont(name: "TrebuchetMS", size: 16)
        messageLabel.sizeToFit()

        backgroundView = messageLabel
    }

     mutating func restore() {
        backgroundView = nil
     }
}