アプリで MWFeedParser ライブラリを使用しようとしています。私のホームスクリーンには、NewsViewController という名前のビュー コントローラーがあります。MWFeedParser ライブラリでは、ルート ビュー コントローラーは RootViewController と呼ばれます。RootViewController から NewsViewController .H + .M にすべてのコードをコピーしようとしました。IB では、テーブルビューを「dataSource」と「delegate」にリンクしました。しかし、私のアプリが起動すると、テーブルビューは空です。コードは次のようになります。
.H:
#import <UIKit/UIKit.h>
#import "MWFeedItem.h"
#import "MWFeedParser.h"
@interface NewsViewController : UITableViewController <MWFeedParserDelegate, UITableViewDelegate, UITableViewDataSource> {
// Parsing
MWFeedParser *feedParser;
NSMutableArray *parsedItems;
// Displaying
NSArray *itemsToDisplay;
NSDateFormatter *formatter;
IBOutlet UITableView *tableView;
}
// Properties
@property (nonatomic, retain) NSArray *itemsToDisplay;
@property (nonatomic, retain) IBOutlet UITableView *tableView;
-(IBAction)goHome;
@end
.M:
#import "NSString+HTML.h"
#import "MWFeedParser.h"
#import "DetailTableViewController.h"
@implementation NewsViewController
@synthesize itemsToDisplay, tableView;
#pragma mark -
#pragma mark View lifecycle
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
self.title = NSLocalizedString(@"News", @"News");
self.tabBarItem.image = [UIImage imageNamed:@"icon_news"]; }
return self;
}
- (void)viewDidLoad
{
label.shadowOffset = CGSizeMake(0.0f, 1.0f);
label.textColor = [UIColor colorWithRed:0xB3/249.0 green:0xB3/252.0 blue:0xB3/253.0 alpha:1];
[super viewDidLoad];
// Do any additional setup after loading the view from its nib.
// Date
// Setup
formatter = [[NSDateFormatter alloc] init];
[formatter setDateStyle:NSDateFormatterShortStyle];
[formatter setTimeStyle:NSDateFormatterShortStyle];
parsedItems = [[NSMutableArray alloc] init];
self.itemsToDisplay = [NSArray array];
// Refresh button
self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemRefresh
target:self
action:@selector(refresh)];
// Parse
NSURL *feedURL = [NSURL URLWithString:@"http://www.mywebsite.com/feed/"];
feedParser = [[MWFeedParser alloc] initWithFeedURL:feedURL];
feedParser.delegate = self;
feedParser.feedParseType = ParseTypeFull; // Parse feed info and all items
feedParser.connectionType = ConnectionTypeAsynchronously;
[feedParser parse];
UIImage *someImage = [UIImage imageNamed:@"back_active1@2x.png"];
[button setBackgroundImage:someImage forState:UIControlStateHighlighted];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (void)viewDidAppear:(BOOL)animated {
static BOOL first = YES;
if (first) {
UIViewController *popup = [[Home1ViewController alloc] initWithNibName:@"Home1ViewController" bundle:nil];
[self presentViewController:popup animated:NO completion:nil];
first = NO;
}
}
#pragma mark -
#pragma mark Parsing
// Reset and reparse
- (void)refresh {
self.title = @"Refreshing...";
[parsedItems removeAllObjects];
[feedParser stopParsing];
[feedParser parse];
self.tableView.userInteractionEnabled = NO;
self.tableView.alpha = 0.3;
}
- (void)updateTableWithParsedItems {
self.itemsToDisplay = [parsedItems sortedArrayUsingDescriptors:
[NSArray arrayWithObject:[[NSSortDescriptor alloc] initWithKey:@"date"
ascending:NO]]];
self.tableView.userInteractionEnabled = YES;
self.tableView.alpha = 1;
[self.tableView reloadData];
}
#pragma mark -
#pragma mark MWFeedParserDelegate
- (void)feedParserDidStart:(MWFeedParser *)parser {
NSLog(@"Started Parsing: %@", parser.url);
}
- (void)feedParser:(MWFeedParser *)parser didParseFeedInfo:(MWFeedInfo *)info {
NSLog(@"Parsed Feed Info: “%@”", info.title);
self.title = info.title;
}
- (void)feedParser:(MWFeedParser *)parser didParseFeedItem:(MWFeedItem *)item {
NSLog(@"Parsed Feed Item: “%@”", item.title);
if (item) [parsedItems addObject:item];
}
- (void)feedParserDidFinish:(MWFeedParser *)parser {
NSLog(@"Finished Parsing%@", (parser.stopped ? @" (Stopped)" : @""));
[self updateTableWithParsedItems];
}
- (void)feedParser:(MWFeedParser *)parser didFailWithError:(NSError *)error {
NSLog(@"Finished Parsing With Error: %@", error);
if (parsedItems.count == 0) {
self.title = @"Failed"; // Show failed message in title
} else {
// Failed but some items parsed, so show and inform of error
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Parsing Incomplete"
message:@"There was an error during the parsing of this feed. Not all of the feed items could parsed."
delegate:nil
cancelButtonTitle:@"Dismiss"
otherButtonTitles:nil];
[alert show];
}
[self updateTableWithParsedItems];
}
#pragma mark -
#pragma mark Table view data source
// Customize the number of sections in the table view.
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return 1;
}
// Customize the number of rows in the table view.
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return itemsToDisplay.count;
}
// Customize the appearance of table view cells.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = @"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier];
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
}
// Configure the cell.
MWFeedItem *item = [itemsToDisplay objectAtIndex:indexPath.row];
if (item) {
// Process
NSString *itemTitle = item.title ? [item.title stringByConvertingHTMLToPlainText] : @"[No Title]";
NSString *itemSummary = item.summary ? [item.summary stringByConvertingHTMLToPlainText] : @"[No Summary]";
// Set
cell.textLabel.font = [UIFont boldSystemFontOfSize:15];
cell.textLabel.text = itemTitle;
NSMutableString *subtitle = [NSMutableString string];
if (item.date) [subtitle appendFormat:@"%@: ", [formatter stringFromDate:item.date]];
[subtitle appendString:itemSummary];
cell.detailTextLabel.text = subtitle;
}
return cell;
}
#pragma mark -
#pragma mark Table view delegate
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
// Show detail
DetailTableViewController *detail = [[DetailTableViewController alloc] initWithStyle:UITableViewStyleGrouped];
detail.item = (MWFeedItem *)[itemsToDisplay objectAtIndex:indexPath.row];
[self.navigationController pushViewController:detail animated:YES];
// Deselect
[self.tableView deselectRowAtIndexPath:indexPath animated:YES];
}
@end