objective-c - 以编程方式创建 View 和 subview

Question

我有以下代码以编程方式创建我的窗口、我的 View 和我的 subview 。问题是我的 subview “filterView2”添加时 [filterView addSubview:filterView2]; 在该行崩溃。我是否忘记包含或做错了什么？谢谢!

    NSRect mainFrame = [[NSScreen mainScreen] frame];
    NSRect helpFrame = NSZeroRect;
    float width = 600;
    float height = 400;
    helpFrame.origin.x = (mainFrame.size.width - width) / 2.0;
    helpFrame.origin.y = 260.0;
    helpFrame.size.width = width;
    helpFrame.size.height = height; 

    helpWindow2 = [[BrightnessView windowWithFrame:helpFrame] retain];

    // Configure window.
    [helpWindow2 setReleasedWhenClosed:YES];
    [helpWindow2 setHidesOnDeactivate:NO];
    [helpWindow2 setCanHide:NO];
    [helpWindow2 setCollectionBehavior:NSWindowCollectionBehaviorCanJoinAllSpaces];
    [helpWindow2 setIgnoresMouseEvents:YES];
    [helpWindow2 setBackgroundColor:[NSColor clearColor]];
    [helpWindow2 setOpaque:NO];


    // Configure contentView.
    NSView *filterView = [helpWindow2 contentView];
    [filterView setWantsLayer:YES];
    //add subview
    NSView *filterView2 = [helpWindow2 contentView];
    [filterView addSubview:filterView2];

    //CALayer for filterView
    CALayer *theLayer = [CALayer layer];
    theLayer.opacity = 0;
    [filterView setLayer:theLayer];
    CGColorRef bgColor = CGColorCreateGenericRGB(0, 200, 255, 1);
    theLayer.backgroundColor = bgColor;
    CGColorRelease(bgColor);
    theLayer.borderColor = CGColorGetConstantColor(kCGColorWhite);
    theLayer.cornerRadius = 8.0;

    float helpOpacity = (([NSApp isActive] ? 1 : 0));
    [[[helpWindow2 contentView] layer] setOpacity:helpOpacity];


    [window addChildWindow:helpWindow2 ordered:NSWindowAbove];

Answer 1

我认为filterView和filterView2是同一个对象，这会导致异常。您不能添加 View 作为其自身的 subview 。