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目标C:rowatindexpath的范围问题单元

objective-c iphone

Oh Danny Boy · 技术社区 · 14 年前

更新:这似乎是“结果”范围的问题。TitleForHeaderInSection似乎不知道“结果”数组的内容。一旦我找到一个解决方案,我会贴出来以防万一有人碰到同样的问题。

如何将cellForRowatindexpath中的每一行设置为由提取请求填充的数组的结果?(按下按钮时发出的提取请求。)

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    //  ... set up cell code here ...
    cell.textLabel.text = [results objectAtIndex:indexPath valueForKey:@"name"];

}

warning: 'NSArray' may not respond to '-objectAtIndexPath:'

编辑:

- (NSArray *)SearchDatabaseForText:(NSString *)passdTextToSearchFor{
    NSManagedObject *searchObj;
    XYZAppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];

    NSManagedObjectContext *managedObjectContext = appDelegate.managedObjectContext;
    NSFetchRequest *request = [[NSFetchRequest alloc] init]; 
    NSPredicate *predicate = [NSPredicate predicateWithFormat:@"name contains [cd] %@", passdTextToSearchFor]; 
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Entry" inManagedObjectContext:managedObjectContext]; 
    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:NO]; 
    NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil];   

    [request setSortDescriptors:sortDescriptors];
    [request setEntity: entity]; 
    [request setPredicate: predicate]; 

    NSError *error;

    results = [managedObjectContext executeFetchRequest:request error:&error];
//  NSLog(@"results %@", results);

    if([results count] == 0){
        NSLog(@"No results found");
        searchObj = nil;
        self.tempString = @"No results found.";
    }else{
        if ([[[results objectAtIndex:0] name] caseInsensitiveCompare:passdTextToSearchFor] == 0) {
            NSLog(@"results %@", [[results objectAtIndex:0] name]);
            searchObj = [results objectAtIndex:0];
        }else{
            NSLog(@"No results found");
            self.tempString = @"No results found.";
            searchObj = nil;
        }       
    }

    [tableView reloadData]; 

    [request release];
    [sortDescriptors release];

    return results;
}

- (void)searchBarSearchButtonClicked:(UISearchBar *)searchBar{
    textToSearchFor =  mySearchBar.text;
    results = [self SearchDatabaseForText:textToSearchFor];
    self.tempString = [myGlobalSearchObject valueForKey:@"name"];   
    NSLog(@"results count: %d", [results count]);
    NSLog(@"results 0: %@", [[results objectAtIndex:0] name]);
    NSLog(@"results 1: %@", [[results objectAtIndex:1] name]);
}
@end

控制台打印:

2010-06-10 16:11:18.581 XYZApp[10140:207] results count: 2
2010-06-10 16:11:18.581 XYZApp[10140:207] results 0: BB Bugs
2010-06-10 16:11:18.582 XYZApp[10140:207] results 1: BB Annie
Program received signal:  âEXC_BAD_ACCESSâ.
(gdb)

编辑2:

英国电信:

#0  0x95a91edb in objc_msgSend ()
#1  0x03b1fe20 in ?? ()
#2  0x0043cd2a in -[UITableViewRowData(UITableViewRowDataPrivate) _updateNumSections] ()
#3  0x0043ca9e in -[UITableViewRowData invalidateAllSections] ()
#4  0x002fc82f in -[UITableView(_UITableViewPrivate) _updateRowData] ()
#5  0x002f7313 in -[UITableView noteNumberOfRowsChanged] ()
#6  0x00301500 in -[UITableView reloadData] ()
#7  0x00008623 in -[SearchViewController SearchDatabaseForText:] (self=0x3d16190, _cmd=0xf02b, passdTextToSearchFor=0x3b29630) 
#8  0x000086ad in -[SearchViewController searchBarSearchButtonClicked:] (self=0x3d16190, _cmd=0x16492cc, searchBar=0x3d2dc50)
#9  0x0047ac13 in -[UISearchBar(UISearchBarStatic) _searchFieldReturnPressed] ()
#10 0x0031094e in -[UIControl(Deprecated) sendAction:toTarget:forEvent:] ()
#11 0x00312f76 in -[UIControl(Internal) _sendActionsForEventMask:withEvent:] ()
#12 0x0032613b in -[UIFieldEditor webView:shouldInsertText:replacingDOMRange:givenAction:] ()
#13 0x01d5a72d in __invoking___ ()
#14 0x01d5a618 in -[NSInvocation invoke] ()
#15 0x0273fc0a in SendDelegateMessage ()
#16 0x033168bf in -[_WebSafeForwarder forwardInvocation:] ()
#17 0x01d7e6f4 in ___forwarding___ ()
#18 0x01d5a6c2 in __forwarding_prep_0___ ()
#19 0x03320fd4 in WebEditorClient::shouldInsertText ()
#20 0x0279dfed in WebCore::Editor::shouldInsertText ()
#21 0x027b67a5 in WebCore::Editor::insertParagraphSeparator ()
#22 0x0279d662 in WebCore::EventHandler::defaultTextInputEventHandler ()
#23 0x0276cee6 in WebCore::EventTargetNode::defaultEventHandler ()
#24 0x0276cb70 in WebCore::EventTargetNode::dispatchGenericEvent ()
#25 0x0276c611 in WebCore::EventTargetNode::dispatchEvent ()
#26 0x0279d327 in WebCore::EventHandler::handleTextInputEvent ()
#27 0x0279d229 in WebCore::Editor::insertText ()
#28 0x03320f4d in -[WebHTMLView(WebNSTextInputSupport) insertText:] ()
#29 0x0279d0b4 in -[WAKResponder tryToPerform:with:] ()
#30 0x03320a33 in -[WebView(WebViewEditingActions) _performResponderOperation:with:] ()
#31 0x03320990 in -[WebView(WebViewEditingActions) insertText:] ()
#32 0x00408231 in -[UIWebDocumentView insertText:] ()
#33 0x003ccd31 in -[UIKeyboardImpl acceptWord:firstDelete:addString:] ()
#34 0x003d2c8c in -[UIKeyboardImpl addInputString:fromVariantKey:] ()
#35 0x004d1a00 in -[UIKeyboardLayoutStar sendStringAction:forKey:] ()
#36 0x004d0285 in -[UIKeyboardLayoutStar handleHardwareKeyDownFromSimulator:] ()
#37 0x002b5bcb in -[UIApplication handleEvent:withNewEvent:] ()
#38 0x002b067f in -[UIApplication sendEvent:] ()
#39 0x002b7061 in _UIApplicationHandleEvent ()
#40 0x02542d59 in PurpleEventCallback ()
#41 0x01d55b80 in CFRunLoopRunSpecific ()
#42 0x01d54c48 in CFRunLoopRunInMode ()
#43 0x02541615 in GSEventRunModal ()
#44 0x025416da in GSEventRun ()
#45 0x002b7faf in UIApplicationMain ()
#46 0x00002578 in main (argc=1, argv=0xbfffef5c) at /Users/default/Documents/iPhone Projects/XYZApp/main.m:14

编辑:

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{
    return[results count];
 }

5 回复 | 直到 12 年前

kennytm 14 年前

没有办法 -objectAtIndex:valueForKey: . 你是说

cell.textLabel.text = [[myArray objectAtIndex:indexPath.row] valueForKey:@"object"];
//                     ^                               ****^

要组合Objective-C方法调用,需要使用多个方括号,如 ^ 还有, -objectAtIndex: 只接受一个nsinteger,但是 indexPath 是nsindxpath。要从索引路径获取行,请使用 .row 属性,如 * s。

编辑:

你好像很困惑 -numberOfSectionsInTableView: 具有 -tableView:numberOfRowsInSection: . 表包含一个或多个节,每个节包含多行(表视图单元格)。

你的桌子只有一部分,所以你应该 return 1 或者只删除此方法,因为1是默认值。实施 -TableView:行杀虫剂数量: 作为

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

Philippe Leybaert 14 年前

我认为你的语法错误。不应该是:

cell.textLabel.text = [[myArray objectAtIndex:indexPath] valueForKey:@"object"];

chuckSaldana 14 年前

我在自己的代码中发现了相同的调试器消息,问题如下:

- (void)viewDidLoad {
    [super viewDidLoad];
    products = [NSArray arrayWithObjects:@"", @"", nil];
}

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {

    return [products count];
}

这很奇怪,但是,当我使用方法计数时,应用程序崩溃了,所有问题都解决了:

@interface theCleass:NSObject {
       NSInteger    theSections;
}
@end

...

- (void)viewDidLoad {
    [super viewDidLoad];
    products = [NSArray arrayWithObjects:@"", @"", nil];

    theSections = [products count];
}

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {

        return theSections;
 }

只需获取viewdidload中元素的数量,虽然我还不知道为什么会发生这种情况,因为我可以在numberofsections中使用count方法:在早期的项目中。

sth ypicasso 14 年前

那是因为

products = [NSArray arrayWithObjects:@"", @"", nil];

是自动释放的对象 retainCount == 1 , 所以当你打电话的时候 return [products count] , the count 属性是已释放对象的属性,因此无法执行此操作。

建议不要执行自动释放对象

products = [[NSArray alloc] initWithObjects:@"", @"", nil];

而且

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

所以当控制器弹出时,产品对象将被销毁

Jahm 12 年前

我想应该是 cell.textLabel.text = [[myArray objectAtIndex: indexPath.row] objectForKey: @"object"];