如何在目标c中向现有数组添加对象

I am new to objective c and having some problem with nsmutableArray.I have button and two textfields on my gui and i want that when i click on button the strings from textfields should be added to my existing array. But the problem is that when i click on button it always create new array.Help anybody.

我是目标c的新手，并且对nsmutableArray有一些问题。我的gui上有按钮和两个文本字段，我希望当我点击按钮时，文本字段中的字符串应该添加到我现有的数组中。但问题是，当我点击按钮时，它总是创建新数组。帮助任何人。

my button code in myfile.m is as follows:

我在myfile.m中的按钮代码如下：

NSMutableArray* myArray = [NSMutableArray array];
NSString *strr=[textf stringValue];
NSString *strr1=[textf1 stringValue];
// [myArray addObject:strr]; // same with float values
// [myArray addObject:strr1];
[myArray addObject:strr];
[myArray addObject:strr1];
int i,j=0;
int count;
for (i = 0, count = [myArray count]; i < count; ){
    NSString *element = [myArray objectAtIndex:i];
    NSLog(@"The element at index %d in the array is: %@", i, element); 
}

1 个解决方案

#1

Because you always create new array in this line:
NSMutableArray* myArray = [NSMutableArray array];

因为你总是在这一行创建新的数组：NSMutableArray * myArray = [NSMutableArray array];

Make your array as property of your class object. Example:

将数组作为类对象的属性。例：

@interface MyClass ()
@property (nonatomic, strong) NSMutableArray * array;
@end

@implementation MyClass

- (id)init {
    self = [super init];
    if ( self ) {
        _array = [NSMutableArray array];
    }
    return self;
}

- (IBAction)onButtonClick {
    NSString *strr = [textf stringValue];
    NSString *strr1 = [textf1 stringValue];

    [self.array addObject:strr];
    [self.array addObject:strr1];

    for ( int i = 0; i < [myArray count]; i++ ) {
        NSString * element = [myArray objectAtIndex:i];
        NSLog(@"The element at index %d in the array is: %@", i, element); 
    }
}

@end

#1