Objective c 无法在OCUnitTest中接收NSInputStream事件

我试图通过单元测试学习如何在iPhone上使用NSInputStream类。我可以使用轮询方法让NSStream从文件中读取数据，但由于某些原因，委托/事件方法不起作用

我已经在下面发布了相关代码。请忽略内存泄漏错误等，因为我只是想确保在将NSStream类应用到更大的项目之前，我知道如何在沙盒环境中使用它

我想知道我是否遗漏了一些关于运行循环如何工作的信息

这是创建拖缆类以从文件读取的逻辑测试

#import "StreamingTests.h"
#import "Streamer.h"

@implementation StreamingTests

- (void) testStream {
    NSLog(@"Starting stream test.");
    Streamer * streamer = [[Streamer alloc] init];

    streamer.usePolling = NO;
    streamer.readingStream = YES;
    NSThread * readThread = [[NSThread alloc] initWithTarget:streamer selector:@selector(startStreamRead:) object:nil];
    [readThread start];
    while(streamer.readingStream) {
        [NSThread sleepForTimeInterval:0.5];
    }
    [readThread cancel];
}

@end

这是一个从NSStream读取的简单测试辅助对象。当usePolling==是时，它读取数据并输出相应的NSLog消息。但是，如果usePolling==否，则永远不会调用委托流事件函数

@implementation Streamer
@synthesize readingStream, usePolling;

- (void) startStreamRead:(NSObject*) context {  
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
    NSLog(@"starting stream read.");
    readingStream = YES;
    /*
     NSURL * url = [NSURL URLWithString:@"http://www.google.com"];
     NSLog(@"Loading: %@",[url description]);
     NSInputStream * inStream = [[NSInputStream alloc] initWithURL:url];
     */
    NSInputStream * inStream = [[NSInputStream alloc] initWithFileAtPath:@"sample.ttc"];

    if(!usePolling) {

        [inStream setDelegate: self];
        [inStream scheduleInRunLoop: [NSRunLoop currentRunLoop]
                            forMode: NSDefaultRunLoopMode];


    }
    [inStream open];

    if(usePolling) {
        while(1) {
            if([inStream hasBytesAvailable]) {
                uint8_t buf[1024];
                unsigned int len = 0;
                len = [(NSInputStream *)inStream read:buf maxLength:1024];
                NSLog(@"Read: %d",len);
            }
            NSStreamStatus status = [inStream streamStatus];
            if(status != NSStreamStatusOpen && status != NSStreamStatusOpening) {
                NSLog(@"Stream not open.");
                break;
            }
        }
        readingStream = NO;

        NSStreamStatus status = [inStream streamStatus];
        NSError * error = [inStream streamError];
        NSLog(@"Status: %d Error Desc: %@ Reason: %@",(int)status,[error localizedDescription], [error localizedFailureReason]);

        [pool release];
    }

}


- (void)stream:(NSStream *)stream handleEvent:(NSStreamEvent)eventCode {
    NSMutableData * _data = nil;
    NSNumber * bytesRead = nil;
    NSLog(@"Event fired.");
    switch(eventCode) {
        case NSStreamEventHasBytesAvailable:
        {
            if(!_data) {
                _data = [[NSMutableData data] retain];
            }
            uint8_t buf[1024];
            unsigned int len = 0;
            len = [(NSInputStream *)stream read:buf maxLength:1024];
            if(len) {
                [_data appendBytes:(const void *)buf length:len];
                // bytesRead is an instance variable of type NSNumber.
                //[bytesRead setIntValue:[bytesRead intValue]+len];
                NSLog(@"Read %d bytes",len);
            } else {
                NSLog(@"no buffer!");
            }
            break;
        }
        case NSStreamEventEndEncountered:
        {
            [stream close];
            [stream removeFromRunLoop:[NSRunLoop currentRunLoop]
                              forMode:NSDefaultRunLoopMode];
            [stream release];
            stream = nil; // stream is ivar, so reinit it
            readingStream = NO;
            break;
        }
        default:
        {
            NSLog(@"Another event occurred.");
            break;
        }
            // continued ...
    }
}

@end

提前感谢,

---

b

原因应该是运行循环被阻塞，因为单元测试正在执行。您可以参考方法的位置

runUntilDate:

可以帮助您在执行单元测试的线程中运行主运行循环，如下所示：

[[NSRunLoop mainRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:1]];

这使run循环运行1秒，以便有时间处理部分文件。应该注意的是，这并不能为单元测试提供可靠的方法，因为时间间隔可能因运行循环大小的不同而不同，因此可能不合适。通过为您的单元提供一个接口，该接口可用于检查输入流读取操作的状态以及读取完成状态，如

-(BOOL)hasFinishedReadingFile

单元测试可以重复执行run循环，直到上述方法返回TRUE并且文件被完全读取

此外：还以不同的方式处理问题