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Question

我有一个问题我想调用一个函数，并使用我从函数中获得的价值，这里是我的函数的代码

-(double)CellWidth{ 
double width; 


if([[UIDevice currentDevice] orientation] == UIDeviceOrientationPortrait || [[UIDevice currentDevice]orientation] == UIDeviceOrientationPortraitUpsideDown){ 
    NSLog(@"Device is now in Portrait Mode"); 
    width = 153.6; 
} 
if ([[UIDevice currentDevice] orientation] == UIDeviceOrientationLandscapeLeft || [[UIDevice currentDevice] orientation] == UIDeviceOrientationLandscapeRight) { 
    NSLog(@"Device is now in LandscapeLeft Mode "); 
    width = 204.6; 
} 

return width; 
} 

该功能是在Class1.m但我也在Class1.h中声明，如下所示 - （double）CellWidth;

现在我想在Class2.h

#import "Class1.h" 
@interface ... 
{ 
Class1 *class1; 
} 
@property (nonatomic,release) Class1 *class1; 

Class2.m

使用它在Class2中

代码，我想用这个

self.TableView.rowHeight = [class1 CellWidth]; 

但CellWidth没有被调用，我没有收到宽度。

Answer 1

您没有传入参数。

你应该有这样的事情：

[self setClass1:[[[Class1 alloc] init] autorelease]]; 

UIInterfaceOrientation orientation = [[UIApplication sharedApplication] statusBarOrientation]; 

//This 
[[self horizontalTableView] setRowHeight:[class1 CellWidth:orientation]]; 

当前的实现并不调用该函数的原因是因为你没有告诉它调用该函数。你告诉它叫[function CellWidth]不[function CellWidth:orientation]

基于您的反馈，你实际上似乎想要更多的东西是这样的：

-(double)CellWidth { 
    double width = 0; 

    UIInterfaceOrientation orientation = [[UIApplication sharedApplication] statusBarOrientation]; 

    if(orientation == UIInterfaceOrientationPortrait) { 
     NSLog(@"PORTRAIT"); 
     width = 153.6; 
    } else if(orientation == UIInterfaceOrientationLandscapeLeft || 
       orientation == UIInterfaceOrientationLandscapeRight) { 
     NSLog(@"LANDSCAPE"); 
     width = 204.6; 
    } 

    return width; 

} 

然后在您的实现，在Class2.m：

[self setClass1:[[[Function alloc] init] autorelease]]; 

//This 
[[self horizontalTableView] setRowHeight:[class1 CellWidth]]; 

为了使这更清楚，我要尝试收拾这个...

CoolCellInfo.h

@interface CoolCellInfo : NSObject { 

} 

-(double)cellWidth; 

@end 

CoolCellInfo.m

@implementation CoolCellInfo 

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

    if(self) { 

    } 

    return self; 
} 

-(double)cellWidth { 
    double width = 0; 

    UIInterfaceOrientation orientation = [[UIApplication sharedApplication] statusBarOrientation]; 

    if(orientation == UIInterfaceOrientationPortrait) { 
     NSLog(@"PORTRAIT"); 
     width = 153.6; 
    } else if(orientation == UIInterfaceOrientationLandscapeLeft || 
       orientation == UIInterfaceOrientationLandscapeRight) { 
     NSLog(@"LANDSCAPE"); 
     width = 204.6; 
    } 

    return width; 
} 

@end 

CoolCellUser.h

#import "CoolCellInfo.h" 

@interface CoolCellUser : NSObject { 
    CoolCellInfo *cellInfo; 
} 

@property (nonatomic, retain) CoolCellInfo *cellInfo; 

@end; 

CoolCellUser.m

@implementation CoolCellUser 
@synthesize cellInfo; 

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

    if(self) { 
     double width = [[self cellInfo] cellWidth]; 

     NSLog(@"Omg cell width = %f", width); 
    } 

    return self; 
} 

#pragma mark Lazy Loader 
-(CoolCellInfo *)cellInfo { 
    if(cellInfo == nil) { 
     [self setCellInfo:[[[CoolCellInfo alloc] init] autorelease]]; 
    } 

    return cellInfo; 
} 

@end 

Answer 2

既然你不Class1中使用任何实例变量，你应该可能实施CellWidth作为class factory method使用+而不是-定义。您可以直接使用类名称[Class1 CellWidth]直接调用它。