objective-c - 主函数上的 Exc_Bad_Access 无法通过类传递实例变量

Question

更新帖子

现在，我在主设备上有 7 次 EXC_BAD_ACCESS，我不知道为什么当 PumpViewHeight 的结果为 607 时，来自 PumpCustomView 类的 heightOfPumpView 结果为 0。

PumpViewController.m

#import "PumpViewController.h"
#import "PumpModel.h"
#import "PumpCustomView.h"

@implementation PumpViewController

@synthesize labels;
@synthesize heightOfPumpView;
- (id)init
{

if (self = [super init]) 
{
    labels = [[PumpModel alloc]init];

    PumpCustomView* pumpView = [PumpCustomView alloc];
    heightOfPumpView = [pumpView pumpViewHeight];
    [labels pumpCreateLabel:heightOfPumpView];
    labelsArray = [[NSMutableArray alloc]initWithArray:[labels labelsGroup]];

    [labels release];

        if (labelsArray!=nil) 
        {
            [pumpView addSubview:[labelsArray objectAtIndex:2]];
        }



    [labelsArray release];
    [pumpView release];
}

return self;
}


-(void) dealloc
{
[super dealloc];

}

@end

PumpModel.m

#import "PumpModel.h"
#import "PumpViewController.h"
#import "PumpCustomView.h"

@implementation PumpModel
@synthesize labelsGroup;

-(id)init
{
self = [super init];
return self;
}

-(void)pumpCreateLabel:(float)pumpViewHeight
{
theNumberOfPump = 8;
PumpViewController* pumpViewControllerAlloc = [PumpViewController alloc];
labelsGroup = [[NSMutableArray alloc]init];

for (int i = 0;i < theNumberOfPump; i++) 
{
    int pumpViewHeight = [pumpViewControllerAlloc heightOfPumpView];
    int pumpViewWidthA = 259;

    int resultHeight = pumpViewHeight/theNumberOfPump;
    CGFloat resultWidth = pumpViewWidthA/2;
    positionChart[i] = resultHeight * i;        

    newLabel[i] = [[NSTextField alloc] init] ;

    [newLabel[i] setIntValue:i];

    newLabel[i].frame = CGRectMake(resultWidth, positionChart[i], 300, 100);
    newLabel[i].font= [NSFont fontWithName:@"Arial" size:12];
    newLabel[i].textColor= [NSColor blackColor];
    newLabel[i].backgroundColor= [NSColor whiteColor];

    [labelsGroup addObject:newLabel[i]];
    [newLabel[i] release];

    NSLog(@"%@ %d",[[labelsGroup objectAtIndex:i] stringValue],positionChart[i]);
}
[pumpViewControllerAlloc release];

}

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

Answer 1

您不应该在[super init]之前向对象发送消息，例如:

- (id)init
{
    if (self = [super init]) 
    {
        [self setNumberOfPump:8];
    }
    return self;
}

这也适用于:

-(id)initWithNumberOfPump:(int)numberOfPump
{
    if (self = [super init]) {
        theNumberOfPump = numberOfPump;
        [self pumpCreateLabel];
    }
    return self ; 
}