刷新XML数据并更新UITableView

我正在开发一个iPhone应用程序,它使用TableView来显示XML数据。XML数据来自外部资源,并被解析并放入对象中,以用作表数据源。应用程序使用一个UItaBar和多个视图控制器,所有这些控件都是以编程方式创建并使用相同的数据源。

一切都很好,很漂亮,但是我想实现一个刷新按钮,这样用户就可以刷新内容(全局,所以所有的视图控制器都应该更新)。解析器将再次查询XML并创建一个新对象。我遇到的问题是,我似乎无法用新数据重新填充TableView。我得到更新的数据对象。但是,实际上更新TableView是一个问题。我已经试过了 setDataSource 并打电话 reloadData ,但这会导致由于未识别的选择器而崩溃。

XML资料是从我的AppDelegate调用的,所有的分析逻辑都在parser.m中。刷新函数在rootviewcontroller.m中调用,它实现了uitableviewdatasource协议:

- (void)refreshXMLFeed:(id)sender {
  NSArray *tableControllersData = [appDelegate getData];
  [self.tableView setDataSource: tableControllersData];
  [self.tableView reloadData];  
}

我该如何处理这个问题?应该获取新数据并像我一直试图完成的那样在rootviewcontroller中重新加载表视图。或者应该在appdelegate中触发数据分析,并且只在rootviewcontroller中重新加载TableView。

如果需要,我可以用必要的代码更新我的问题,我不确定在这一点上哪些部分是相关的。

rootview控制器.h:

#import <UIKit/UIKit.h>

@interface RootViewController : UITableViewController {
  MyAppDelegate *appDelegate;
  NSArray *tableDataArray;
}

@property (nonatomic, retain) NSArray *tableDataArray;

- (IBAction)refreshXMLFeed:(id)sender;
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil tableDataSource:(NSArray*)tableData;

@end

rootview控制器.m:

#import "CustomCell.h"
#import "MyAppDelegate.h"
#import "RootViewController.h"
#import "DetailViewController.h"

@implementation RootViewController
@synthesize tableDataArray;

- (void)viewDidLoad {
  [super viewDidLoad];
}

//Override the default initWithNibName method
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil tableDataSource:(NSArray*)tableData {
  if (self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]) {
    // Custom initialization
    tableDataArray = [tableData retain];   
  }
  return self;
}

-(void)viewWillAppear:(BOOL)animated {
  appDelegate = (MyAppDelegate *)[[UIApplication sharedApplication] delegate];    
  [super viewWillAppear:animated];
  //Set the colour of the navigationController and add buttons
  self.navigationController.navigationBar.tintColor = [UIColor blackColor];

  //Add the refresh button
  UIBarButtonItem* refreshButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemRefresh target:self action:@selector(refreshXMLFeed:)];
  [self.navigationItem setLeftBarButtonItem:refreshButton animated:YES];
  [refreshButton release];  
}

#pragma mark Table

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
  return [self.tableDataArray count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
  static NSString *CustomCellIdentifier = @"CustomCellIdentifier";
  CustomCell *cell = (CustomCell *)[tableView dequeueReusableCellWithIdentifier: CustomCellIdentifier];
  if (cell == nil) {
    NSArray *cellNib = [[NSBundle mainBundle] loadNibNamed:@"CustomCell" owner:self options:nil];
    for (id oneObject in cellNib) {
      if ([oneObject isKindOfClass:[CustomCell class]]) {
        cell = (CustomCell *)oneObject;
      }
    }
  }

  NSUInteger row = [indexPath row];
  NSDictionary *rowData = [self.tableDataArray objectAtIndex:row];
  cell.colorLabel.text = [rowData objectForKey:@"Type"];
  cell.nameLabel.text = [rowData objectForKey:@"Name"];
  UIImage *image = [UIImage imageNamed:[rowData objectForKey:@"Icon"]];
  cell.image = image;
  return cell;
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
  NSString *selectedRow = [tableDataArray objectAtIndex:indexPath.row];

  DetailViewController *detailViewController = [[DetailViewController alloc] initWithNibName:@"DetailView" bundle:[NSBundle mainBundle]];
  detailViewController. selectedRow = selectedRow;
  [self.navigationController pushViewController:detailViewController animated:YES];

  UIBarButtonItem *backButton = [[UIBarButtonItem alloc] init];
  backButton.title = @"Back";
  self.navigationItem.backBarButtonItem = backButton;
  [backButton release];  
  [detailViewController release];
  detailViewController = nil;
}

#pragma mark Refresh

- (void)refreshXMLFeed:(id)sender {
  NSArray *tableControllersData = [appDelegate getData];
  [self.tableView setDataSource: tableControllersData];
  [self.tableView reloadData];  
}

- (void)didReceiveMemoryWarning {
    // Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];

    // Release any cached data, images, etc that aren't in use.
}

- (void)viewDidUnload {
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
}


- (void)dealloc { 
    [super dealloc];
}

@end