的NSView makeBackingLayer与CALayer的子类显示没有输出(NSView m

2019-10-28 22:44发布

这是我的问题的延续停的NSView-的drawRect结算前方的绘图lockfocus,不再视为工作-ON-莫哈韦 。 我用图案lockFocus图形上下文flushWindow图案绘制到另一视图。 这不再工作在MacOS 10.14,为的意见后备存储已更改(新的二进制文件)。

的NSView有一个方法makeBackingLayer是不是有没出息,我猜。 下面的代码片段已经makeBackingLayer叫了,我可以把它用我的CALayer子类“TransparentLayer”,成功。 成功至今,我的子类的drawInContext:确实叫,因为它应该,setNeedsDisplay被称为层后。 但是,任何图纸我似乎不存在。 我究竟做错了什么? (ScreenRect是全屏RECT)。

我的NSView(全屏):

- (id)initWithFrame:(NSRect)frame
{
    ALog(@"");

    self = [super initWithFrame:frame];
    if (self) {
        self.wantsLayer = YES;
    }
    return self;
}

- (BOOL) isOpaque { return NO; }
- (BOOL) wantsLayer { return YES; }  // YES for layers, else drawRect
- (BOOL) wantsUpdateLayer { return YES; }

- (CALayer *)makeBackingLayer
// NB: If self.layer is already set, makeBackingLayer is NOT called
{
    ALog(@"");

    // OWN LAYER TYPE (simply subclass of CALayer)
    TransparentLayer *newLayer = [[TransparentLayer alloc] initWithFrame:ScreenRect];
    return newLayer;
}

- (void)updateLayer { ALog(@"(we do not want this)"); }  // (not called)

- (void)drawInContext:(CGContextRef)ctx { ALog( @"ctx=%p",ctx ); } // (not called)

- (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx { ALog( @"layer=%p ctx=%p",layer,ctx ); } // (not called)

- (void)drawRect:(NSRect)dirtyRect { ALog(@""); } // (not called)

TransparentLayer(全屏,太):

- (id)initWithFrame:(NSRect)frame
{
    ALog(@"");

    self = [super init];
    if (self) {        
        self.bounds = frame;    // ?
        self.frame = frame;     // ?
        self.contentsRect = frame;

        self.backgroundColor = [NSColor clearColor].CGColor;  // transparent
        self.opaque = NO;            
    }
    return self;
}

- (void)updateLayer
{
    ALog(@"");
}

- (void)_OUT_display
// THIS (display) IS CALLED when this method is present, else drawInContext:
{
    ALog(@"");
}


- (void)drawInContext:(CGContextRef)ctx
// THIS IS CALLED, BUT NO OUTPUT VISIBLE ON SCREEN
// ViewController calls every cycle: [self.stillView.layer setNeedsDisplay];
{
    ALog(@"");

    // Draw a BLUE square 50x50, screen bottom, left
    CGRect R = CGRectMake(0., 0., 50., 50.  );
    CGContextSetRGBFillColor(ctx, 0,0,1, 1);  // BLUE
    CGContextFillRect(ctx, R);
}
文章来源: NSView makeBackingLayer with CALayer subclass displays no output