链接器错误OBJC_CLASS _ $ _ AVAudioPlayer”

Question

Hello Everyone,

[Error: objc-class-ref in ViewController.o
    ld: symbol(s) not found for architecture i386
    clang: error: linker command failed with exit code 1 (use -v to see invocation)] 

I am running an application which will produce sound after button is clicked ,

I have included all the framework for audio after seeing the error

 [ objc-class-ref in ViewController.o
        ld: symbol(s) not found for architecture i386
        clang: error: linker command failed with exit code 1 (use -v to see invocation)
        ]

from stack overflow but still its not working for me .. please look at the below code i have included my .h and .m file and suggest me some solution

It May be an linker error but i have included the framework from build phase and included #import framework ..Please check out my below Code if i am missing something please let me know ... I am self learning beginner for iPhone Development ..

        //  ViewController.h



        //  Audioplaying
        //
        //  Created by Vaibhav on 12/31/12.
        //  Copyright (c) 2012 __MyCompanyName__. All rights reserved.
        //

        #import <UIKit/UIKit.h>
        #import <AVFoundation/AVAudioPlayer.h>
         #import <AudioToolbox/AudioToolbox.h>


        @interface ViewController : UIViewController <AVAudioPlayerDelegate >

        {
            AVAudioPlayer *player;
            UIButton *playButton;
        }

        @property (nonatomic, retain) AVAudioPlayer *player;
        @property (nonatomic, retain) IBOutlet UIButton *playButton;

        - (IBAction) play;

        @end


    //
    //  ViewController.m
    // 
    #import "ViewController.h"
    #import <AVFoundation/AVAudioPlayer.h>

    @implementation ViewController

    @synthesize player, playButton;


    - (void)viewDidLoad {

        // grab the path to the caf file
        NSString *soundFilePath =
        [[NSBundle mainBundle] pathForResource: @"blip"
                                        ofType: @"caf"];

        NSURL *fileURL = [[NSURL alloc] initFileURLWithPath: soundFilePath];

        // create a new AVAudioPlayer initialized with the URL to the file
        AVAudioPlayer *newPlayer =
        [[AVAudioPlayer alloc] initWithContentsOfURL:fileURL error:nil];


        // set our ivar equal to the new player
        self.player = newPlayer;


        // preloads buffers, gets ready to play
        [player prepareToPlay];
        // set delegate so we can get called back when the sound has finished playing
        [player setDelegate: self];

        [super viewDidLoad];
    }

    // delegate method
    - (void) audioPlayerDidFinishPlaying: (AVAudioPlayer *) player
                            successfully: (BOOL) completed {
        if (completed == YES) {
            self.playButton.enabled = YES;
        }
    }


    // 
    - (IBAction) play {

        self.playButton.enabled = NO;
        [self.player play];

    }
    - (void)viewDidUnload
    {
        [super viewDidUnload];
        // Release any retained subviews of the main view.
        // e.g. self.myOutlet = nil;
    }

    - (void)viewWillAppear:(BOOL)animated
    {
        [super viewWillAppear:animated];
    }

    - (void)viewDidAppear:(BOOL)animated
    {
        [super viewDidAppear:animated];
    }

    - (void)viewWillDisappear:(BOOL)animated
    {
        [super viewWillDisappear:animated];
    }

    - (void)viewDidDisappear:(BOOL)animated
    {
        [super viewDidDisappear:animated];
    }

    - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
    {
        // Return YES for supported orientations
        return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
    }

    @end

Error :

Build target Audioplaying

Ld /Users/vaibhav/Library/Developer/Xcode/DerivedData/Audioplaying-eaaytfuwbstsyffgakkifipcygeu/Build/Products/Debug-iphonesimulator/Audioplaying.app/Audioplaying normal i386
    cd "/Users/vaibhav/Iphone projects/Audioplaying"
    setenv MACOSX_DEPLOYMENT_TARGET 10.6
    setenv PATH "/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin:/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"
    /Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/clang -arch i386 -isysroot /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator5.0.sdk -L/Users/vaibhav/Library/Developer/Xcode/DerivedData/Audioplaying-eaaytfuwbstsyffgakkifipcygeu/Build/Products/Debug-iphonesimulator -F/Users/vaibhav/Library/Developer/Xcode/DerivedData/Audioplaying-eaaytfuwbstsyffgakkifipcygeu/Build/Products/Debug-iphonesimulator "-F/Users/vaibhav/Iphone projects/Audioplaying" -filelist /Users/vaibhav/Library/Developer/Xcode/DerivedData/Audioplaying-eaaytfuwbstsyffgakkifipcygeu/Build/Intermediates/Audioplaying.build/Debug-iphonesimulator/Audioplaying.build/Objects-normal/i386/Audioplaying.LinkFileList -mmacosx-version-min=10.6 -Xlinker -objc_abi_version -Xlinker 2 -fobjc-arc -Xlinker -no_implicit_dylibs -D__IPHONE_OS_VERSION_MIN_REQUIRED=50000 -framework AVFoundation -framework UIKit -framework Foundation -framework CoreGraphics -o /Users/vaibhav/Library/Developer/Xcode/DerivedData/Audioplaying-eaaytfuwbstsyffgakkifipcygeu/Build/Products/Debug-iphonesimulator/Audioplaying.app/Audioplaying

ld: warning: ignoring file /Users/vaibhav/Iphone projects/Audioplaying/AVFoundation.framework/AVFoundation, file was built for unsupported file format which is not the architecture being linked (i386)
Undefined symbols for architecture i386:
  "_OBJC_CLASS_$_AVAudioPlayer", referenced from:
      objc-class-ref in ViewController.o
ld: symbol(s) not found for architecture i386
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Answer 1

只需从Build Phases=>Link Binaries With Libraries添加Foundation.framework和AVFoundation.framework框架，然后尝试即可。

Answer 2

You have somehow created your own broken framework named AVFoundation.framework inside your project. The presence of this broken framework is preventing the linker from using the system's AVFoundation framework.

You need to delete /Users/vaibhav/Iphone projects/Audioplaying/AVFoundation.framework and everything in it.