Show image from binary stream - ios

Question

I want to display an PNG-image I get via binary stream when I send a nullbyte to the server.
I do get information from the stream. But the image is never shown and I don't know why. Maybe someone sees a mistake.
My code is following:
#import <UIKit/UIKit.h>
NSInputStream *inputStream;
NSOutputStream *outputStream;
#interface ViewController : UIViewController <NSStreamDelegate>
#property (weak, nonatomic) IBOutlet UIView *secondView;
#property (weak, nonatomic) IBOutlet UIImageView *imageView;
- (IBAction)sendNullbyte:(id)sender;
#property (weak, nonatomic) IBOutlet UIView *firstView;
#property (nonatomic, strong, readwrite) NSOutputStream *fileStream;
#end
and
#import "ViewController.h"
#interface ViewController ()
#end
#implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
[self initNetworkCommunication];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
}
- (void)initNetworkCommunication {
CFReadStreamRef readStream;
CFWriteStreamRef writeStream;
CFStreamCreatePairWithSocketToHost(NULL, (CFStringRef)#"localhost", 80, &readStream, &writeStream);
inputStream = (__bridge NSInputStream *)readStream;
outputStream = (__bridge NSOutputStream *)writeStream;
[inputStream setDelegate:self];
[outputStream setDelegate:self];
[inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
[outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
[inputStream open];
[outputStream open];
}
- (void)stream:(NSStream *)theStream handleEvent:(NSStreamEvent)streamEvent{
switch (streamEvent) {
case NSStreamEventOpenCompleted:
NSLog(#"Stream opened");
break;
case NSStreamEventHasBytesAvailable:
NSLog(#"Has bytes available.");
//be sure that event comes from input stream
if(theStream == inputStream){
UInt8 buffer[500000];
long len;
BOOL firstbytes = true;
//read method returns 0 when there is nothing left in the stream
len = [inputStream read:buffer maxLength:sizeof(buffer)];
if (len > 0){
NSData *output = [[NSData alloc] initWithBytes:buffer length:len-4];
if (output != nil){
NSLog(#"server said: %#", output);
UIImage *image = [[UIImage alloc] initWithData:output];;
_imageView.image = image;
}
}
}
break;
case NSStreamEventErrorOccurred:
NSLog(#"Cant not connect to the host");
break;
case NSStreamEventEndEncountered:
break;
default:
break;
}
}
- (IBAction)sendNullbyte:(id)sender {
NSInteger nullbyte = 0x00;
NSData *data =[[NSData alloc] initWithBytes:&nullbyte length:1];
[outputStream write:[data bytes] maxLength:[data length]];
[self.view bringSubviewToFront:_secondView];
}
#end

Answer 1

Try to use unit8_t instead UInt8, and make sure that u handle the case that the image doesn't get to u in a single packet...
U can do something like this:
{
NSMutableData *data; // ivar
}
// init it somewhere
data = [NSMutableData new];
case NSStreamEventHasBytesAvailable:
if (theStream == inputStream) {
uint8_t buffer[5000];
int length;
while ([inputStream hasBytesAvailable]) {
length = [inputStream read:buffer maxLength:sizeof(buffer)];
if (length > 0) {
[data appendBytes:(const void *)buffer length];
}
}
}
break;
case NSStreamEventEndEncountered:
{
if (theStream == inputStream) {
UIImage *imagess = [[UIImage alloc]initWithData:data];
[imagesview setImage:imagess];
}
} break;