設置的NSMutableArray新的NSMutableArray

Question

@implementation RightViewController{ 
    NSMutableArray * tableArray; 
} 

@synthesize tableView; 

- (void)viewDidLoad { 
    [super viewDidLoad]; 
    tableArray = [[NSMutableArray alloc] init]; 
} 


- (void)refreshTable: (NSMutableArray*)resultsArray{ 
    [tableArray setArray:resultsArray];  
    NSLog(@"resultsArray : %d : %d", [tableArray count] , [resultsArray count]); 

    [self.tableView reloadData]; 
} 

這表明我：resultsArray：0：78

爲什麼我不能設置信息這陣？ 我這樣從另一個控制器調用refreshTable：

[[[RightViewController alloc] init] refreshTable:resultsArray]; 

更新時間：

tableArray = [NSMutableArray arrayWithArray:resultsArray]; 

爲我工作。

後，我做的

- (IBAction)reloadTableButton:(id)sender { 
    [self refreshTable:tableArray]; 
} 

，它的顯示我：resultsArray：0：0

爲什麼tableArray數組是空的？

Answer 1

嘗試設置你的tableArray變量，像這樣：

tableArray = [NSMutableArray arrayWithArray:resultsArray]; 

你可能不會保留你的可變數組我建議作出@property您tableArray。將在此之前你@synthesize

@property (retain, nonatomic) NSMutableArray *tableArray; 

Answer 2

我相信它應該工作

RightViewController *controller = [[RightViewController alloc] init]; 
[controller refreshTable:resultsArray]; 

Answer 3

@implementation RightViewController{ 
    NSMutableArray * tableArray; 
} 
@property (strong, nonatomic) NSMutableArray *tableArray; //use the keyword "retain" instead of "strong" in below iOS 5 

@synthesize tableView; 
@synthesize tableArray; 

- (void)viewDidLoad { 

    [super viewDidLoad]; 
    self.tableArray = [[NSMutableArray alloc] init]; 
} 


- (void)refreshTable: (NSMutableArray*)resultsArray{ 

    self.tableArray = resultsArray; 

    NSLog(@"resultsArray : %d : %d", [tableArray count] , [resultsArray count]); 

    [self.tableView reloadData]; 
} 

Answer 4

選項1：

- (void)viewDidLoad { 
    [super viewDidLoad]; 
    //don't do anything with the array here! 
    //refreshTable may well be called before the view is loaded 
} 


- (void)refreshTable: (NSMutableArray*)resultsArray{ 

    if (!self.tableArray) // if it does not exist, then create it on the fly. 
     self.tableArray = [[NSMutableArray alloc] init]; 
    [tableArray setArray:resultsArray];  
    [self.tableView reloadData]; 
} 

選項2：

- (MyClass*) init { 
    self = [super init]; 
    if (self) { 
    self.tableArray = [[NSMutableArray alloc] init]; 
    } 
} 

- (void)viewDidLoad { 
    [super viewDidLoad]; 
    //don't do anything with the array here! 
} 


- (void)refreshTable: (NSMutableArray*)resultsArray{ 
    [tableArray setArray:resultsArray]; // you can be sure that init was invoked earlier.  
    [self.tableView reloadData]; 
} 

方案3：

- (void)viewDidLoad { 
    [super viewDidLoad]; 
    //don't do anything with the array here! 
} 


- (void)refreshTable: (NSMutableArray*)resultsArray{ 
    self.tableArray = [NSMutalbeArray arrayWithArray:resultsArray]; //This creates a new array as a copy of resultsArray and assigns it to tableArray. No need to initialize anything. 
    [self.tableView reloadData]; 
}