内存泄漏NSBlockOperation

Question

我使用在该操作中声明的对象声明了NSBlockOperation。由于内存问题，我的应用程序不断崩溃。感谢任何关于这个问题的很好解释的暗示，花了几个小时还是没有成功。

运行时:内存问题- (5种泄漏类型)：NSExactBlockVariable的一个实例泄漏

- (EMUserInfoOperation*)loadingLocalModelOperationWithColor:(EMOutfitColor)outfitColor gender:(EMGender)gender {

__block EMUserInfoOperation* operation = [EMUserInfoOperation blockOperationWithBlock:^{
    NSURL* remoteURL = [NSURL URLWithString:self.settings[kEMRemoteUrlKey]];

    EMOutfitModel* model = nil;

    if (remoteURL == nil) {
        model = [[EMDomainDataLoader sharedLoader] loadEmbededOutfitNamed:self.name gender:gender];
    } else {
        model = [[EMDomainDataLoader sharedLoader] loadCachedOutfitNamed:self.name withVersion:self.version gender:gender];
    }
    [model syncApplyTextureFromPath:[self texturePathForColor:outfitColor] textureSampler:EMTextureSamplerColor];

    NSString *alphaPath = [self texturePathForAlpha];
    if(alphaPath.length > 0) {
        [model syncApplyTextureFromPath:alphaPath textureSampler:EMTextureSamplerAlpha];
    }

    operation.userInfo = model;
}];

return operation;
}

Answer 1

我猜您的EMUserInfoOperation对象对创建操作的块有很强的引用。这个块还具有对EMUserInfoOperation对象的强烈引用，因为它捕获了operation变量。所以你有一个保留周期。

通过执行以下操作，可以使块仅弱引用EMUserInfoOperation对象：

EMUserInfoOperation* operation;
__block __weak typeof(operation) weakOperation;
weakOperation = operation = [EMUserInfoOperation blockOperationWithBlock:^{
    typeof(operation) strongOperation = weakOperation;
    if (strongOperation) {

        // ...

        strongOperation.userInfo = model;
    }
}];
return operation;