如何在iphone中將NSArray數據分配給NSMutableArray？

Question

在我的應用程序中，我有一個包含一些數據的NSArray。 我想獲取該數據並將其放入名為subArrayData的NSMutableArray 。 我能夠將我的第一個數組中的數據插入到可變數組中，但是當應用程序運行時，我得到：

警告：從'nsarray *'分配給'nsmutablearray *'的指針類型不兼容請幫幫忙。

以下是我的代碼：.h文件

#import <UIKit/UIKit.h>

@interface AddNew : UIViewController
{
    NSMutableArray *subArrayData;;
}
@property(nonatomic ,retain)NSMutableArray *subArrayData;

.m文件

#import "AddNew.h"
#import "DashBoardPage.h"
#import "SubmitYourListing.h"


@implementation AddNew

@synthesize subArrayData;

-(void)accommodationAndTravel
{
    subArrayData =[[NSArray alloc] initWithArray:[NSArray arrayWithObjects:@"Select one",@"Accommodation and travel hospitality",@"Apartments and villas",@"Bed and Breakfast",@"Caravan parks and campsites",@"Hospitality",
                                                  @"Hotels and Motels",@"Snow and Ski lodges",@"Tourist attractions and tourism information",@"Tours and Holidays",@"Travel agents and Services",nil]];


}

Answer 1

您可以通過調用其-mutableCopy方法將任何NSArray轉換為NSMutable數組：

NSArray *someArray = ...;
NSMutableArray* subArrayData = [someArray mutableCopy];

Answer 2

更改.m文件

#import "AddNew.h"
#import "DashBoardPage.h"
#import "SubmitYourListing.h"


@implementation AddNew

@synthesize subArrayData;

-(void)accommodationAndTravel
{
    subArrayData =[[NSMutableArray alloc] initWithArray:[NSArray arrayWithObjects:@"Select one",@"Accommodation and travel hospitality",@"Apartments and villas",@"Bed and Breakfast",@"Caravan parks and campsites",@"Hospitality",
                                                  @"Hotels and Motels",@"Snow and Ski lodges",@"Tourist attractions and tourism information",@"Tours and Holidays",@"Travel agents and Services",nil]];


}

Answer 3

只需調用一個NSMutableArray的初始值設定項，如下所示：

subArrayData = [[NSMutableArray alloc] initWithObjects:
                                        @"Select one",
                                        @"Accommodation and travel hospitality",
                                        @"Apartments and villas",
                                        @"Bed and Breakfast",
                                        @"Caravan parks and campsites",
                                        @"Hospitality",
                                        @"Hotels and Motels",
                                        @"Snow and Ski lodges",
                                        @"Tourist attractions and tourism information",
                                        @"Tours and Holidays",
                                        @"Travel agents and Services",
                                        nil]];

對於處理現有NSArray ，您可以制作mutableCopy ：

- (id)initWithArray:(NSArray *)array
{
  self = [super init];
  if (nil != self) {
    subArrayData = [array mutableCopy];
    ...