无法检测内存泄漏的原因

Question

根据 Xcode 的仪器泄漏工具，在这个函数中，我在两个位置有内存泄漏。

我没有启用 ARC，也无法激活它，所以我必须以另一种方式进行管理。

+(NSArray *)changePolygonFrom:(NSArray *)polygon size:(float)size{

    int nmrOfPoints = [polygon count];
    double x[nmrOfPoints];
    double y[nmrOfPoints];
    for (int i = 0; i < nmrOfPoints; i++) {
        CGPoint p = [[polygon objectAtIndex:i] CGPointValue];
        x[i] = p.x;
        y[i] = p.y;
    }

    insetPolygon(x,y,nmrOfPoints,size);

    NSMutableArray *rPolygon = [[NSMutableArray alloc] initWithCapacity:nmrOfPoints];
    for(int i = 0; i < nmrOfPoints; i++){
        CGPoint p = CGPointMake(x[i], y[i]);
        NSValue *val = [NSValue valueWithCGPoint:p];
        [rPolygon addObject:val];
    }

    return rPolygon;
}

这就是我所说的

-(void)fixFuzArrays{
    if (fuzzFix) {
        largeFuzzPolygon = [Triangulation changePolygonFrom:normalPolygon size:(shortestDistance/2)];
        smallFuzzPolygon = [Triangulation changePolygonFrom:normalPolygon size:(shortestDistance/6)];
    }else{
        largeFuzzPolygon = [Triangulation changePolygonFrom:normalPolygon size:-(shortestDistance/2)];
        smallFuzzPolygon = [Triangulation changePolygonFrom:normalPolygon size:-(shortestDistance/6)];
    }
}

如果我在 rPolygon 上使用自动释放，我会在 iFrame 和 oFrame 对象上获得 BAD_ACCESS，它们是前一个函数的返回产品

-(void)drawAreaFuzzWithOuterFrame:(NSArray *)oFrame andInnerFrame:(NSArray *)iFrame withColor:(ccColor4B)c{
    for(int i = 0; i < [oFrame count]; i++){

        CGPoint oP1 = [[oFrame objectAtIndex:i] CGPointValue];
        CGPoint iP1 = [[iFrame objectAtIndex:i] CGPointValue];

        CGPoint oP2;
        CGPoint iP2;

        if(i == [oFrame count]-1){
            oP2 = [[oFrame objectAtIndex:0]   CGPointValue];
            iP2 = [[iFrame objectAtIndex:0]   CGPointValue];
        }else{
            oP2 = [[oFrame objectAtIndex:i+1]   CGPointValue];
            iP2 = [[iFrame objectAtIndex:i+1]   CGPointValue];
        }

        GLfloat vertices[] = {
            oP1.x,oP1.y,
            oP2.x,oP2.y,
            iP1.x,iP1.y,
            iP2.x,iP2.y,
        };

        GLubyte colors[] = {
            c.r,c.g,c.b,c.a,
            c.r,c.g,c.b,c.a,
            c.r,c.g,c.b,0,
            c.r,c.g,c.b,0,
        };

        BEdrawGLShapeWithVertices(vertices, colors);
    }
}

Answer 1

您必须在返回之前自动释放数组，然后将数组保留在接收它的方法中

将autorelease 添加到NSMutableArray

NSMutableArray *rPolygon = [[[NSMutableArray alloc] initWithCapacity:nmrOfPoints] autorelease];

然后在使用你的函数的方法上加上保留，但你必须稍后释放它

NSArray *myArray = [[MyClass changePolygonFrom:array size:size] retain];

别忘了稍后发布myArray

Answer 2

您必须将 NSMutableArray 标记为自动释放：

NSMutableArray *rPolygon = [[[NSMutableArray alloc] initWithCapacity:nmrOfPoints] autorelease];

如果你不这样做，你就是在创建它，保留它，然后返回它。它从未发布过。

Answer 3

您在声明 rPolygon 时忘记了自动释放：

NSMutableArray *rPolygon = [[[NSMutableArray alloc] initWithCapacity:nmrOfPoints] autorelease];

编辑 看来你没有保留+(NSArray *)changePolygonFrom:(NSArray *)polygon size:(float)size方法的结果。

尝试更改保留largeFuzzPolygon 和smallFuzzPolygon 的代码（记住也要在dealloc 方法中释放它们）：

-(void)fixFuzArrays{
    [largeFuzzPolygon release];
    [smallFuzzPolygon release];

    if (fuzzFix) {
        largeFuzzPolygon = [[Triangulation changePolygonFrom:normalPolygon size:(shortestDistance/2)] retain];
        smallFuzzPolygon = [[Triangulation changePolygonFrom:normalPolygon size:(shortestDistance/6)] retain];
    }else{
        largeFuzzPolygon = [[Triangulation changePolygonFrom:normalPolygon size:-(shortestDistance/2)] retain];
        smallFuzzPolygon = [[Triangulation changePolygonFrom:normalPolygon size:-(shortestDistance/6)] retain];
    }
}

或者更好，我建议您合成它们并使用以下代码：

-(void)fixFuzArrays{
    if (fuzzFix) {
        self.largeFuzzPolygon = [[Triangulation changePolygonFrom:normalPolygon size:(shortestDistance/2)] retain];
        self.smallFuzzPolygon = [[Triangulation changePolygonFrom:normalPolygon size:(shortestDistance/6)] retain];
    }else{
        self.largeFuzzPolygon = [[Triangulation changePolygonFrom:normalPolygon size:-(shortestDistance/2)] retain];
        self.smallFuzzPolygon = [[Triangulation changePolygonFrom:normalPolygon size:-(shortestDistance/6)] retain];
    }
}