如何在鼠标上突出显示IKImageBrowserView的单元格？

Question

我想提供一些反馈，当鼠标在IKImageBrowserView的某个单元上结束时。

具体而言，我想稍微调整单元格大小，使其在鼠标悬停时显示稍大。或者，突出显示背景/边框将会很好。

不幸的是，IKImageBrowserCell不是NSCell的子类，而是NSObject，我无法在API中找到解决方案。有任何想法吗？

Answer 1

您可以尝试继承IKImageBrowserView并将NSTrackingArea添加到可见矩形。您可以使用-indexOfItemAtPoint:然后implement -mouseMoved: to work with the tracking area找到正确的图像单元，然后通过使用-itemFrameAtIndex:来获取其框架。您可以在新发现的框架上添加您自己的图层（或无边界窗口），并使用标准动画来增长/缩小/动画/发光/摇动/缩放图像，而不是尝试使用IKImageBrowserView的黑盒图层和绘图。无论这个“欺骗”细胞。让点击“通过”（并隐藏你的“欺骗”单元格），这样正常的拖放机制的作用是一样的。 IKImageBrowserView有它自己的-setForegroundLayer：方法，允许你添加一个“覆盖层” - 完全适合这个目的，我想象。

这是我第一次尝试解决这个问题，如果它是我自己的。

Answer 2

虽然这已经被回答（虽然没有代码），但我也遇到了相同的要求，我通过继承IKImageBrowswerView来实现它。下面是我的代码，我希望它能帮助别人。要使用它，只需在xib/nib/storyboard中将类图像浏览器视图设置为CustomIKImageBrowserView，然后将下面的类添加到项目中即可。

 #import <Quartz/Quartz.h> 
    #import "CustomizableNSView.h" 
    @interface CustomIKImageBrowserView : IKImageBrowserView 
    { 
     NSTrackingArea *trackingArea; 
     NSInteger lastHoverIndex; 
     CustomizableNSView *hoverView ; 
    } 
    @end 

和实现类是：

#import "CustomIKImageBrowserView.h" 

    @implementation CustomIKImageBrowserView 

- (void)awakeFromNib { 
    [self addCustomTrackingAreaToChangeMouseCursor]; 
} 

- (void) updateTrackingAreas { 
    if (trackingArea) 
     [self removeTrackingArea:trackingArea]; 
    [self addCustomTrackingAreaToChangeMouseCursor]; 
} 

- (void) addCustomTrackingAreaToChangeMouseCursor{ 
    trackingArea = [[NSTrackingArea alloc] initWithRect:self.bounds options:NSTrackingMouseEnteredAndExited | NSTrackingActiveAlways | NSTrackingMouseMoved owner:self userInfo:nil]; 
    [self addTrackingArea:trackingArea]; 
} 

- (void) mouseMoved:(NSEvent *)theEvent{ 
    NSPoint currentPosition = [self convertPoint:[theEvent locationInWindow] fromView:nil]; 

    NSInteger idx = [self indexOfItemAtPoint:currentPosition]; 
    if(idx != NSNotFound) { 
     [[NSCursor pointingHandCursor] push]; 
     //NSLog(@"DslrIKImageBrowserView = %ld and %ld",idx,lastHoverIndex); 
     if (lastHoverIndex == idx) { 
      return; 
     } else { 
      if(hoverView) 
       [hoverView removeFromSuperview]; 
     } 

     lastHoverIndex = idx; 
     IKImageBrowserCell *cell = [self cellForItemAtIndex:idx]; 
     NSRect r = cell.imageFrame; 
     r.size.width = r.size.width + 6; 
     r.size.height = r.size.height + 6; 
     r.origin.x = r.origin.x - 3; 
     r.origin.y = r.origin.y - 3 ; 

     hoverView = [[CustomizableNSView alloc] initWithFrame:r]; 
     hoverView.borderColor = [NSColor colorWithCalibratedRed:136/255.0 green:185/255.0 blue:236/255.0 alpha:1.0]; 
     hoverView.borderRadious = 0; 
     hoverView.borderWidth = 6; 
     hoverView.backgroundColor = [NSColor colorWithCalibratedRed:0 green:191.0/255.0 blue:1.0 alpha:0.3]; 
     [self.superview addSubview:hoverView]; 

    } else 
    { 
     lastHoverIndex = -1; 
     [[NSCursor arrowCursor] push]; 
     if(hoverView) 
      [hoverView removeFromSuperview]; 
    } 
} 

- (void)mouseEntered:(NSEvent *)theEvent{ 
    [[NSCursor pointingHandCursor] push]; 
} 

- (void) mouseExited:(NSEvent *)theEvent{ 
    //[[NSCursor arrowCursor] push]; 
    lastHoverIndex = -1; 
    if(hoverView) [hoverView removeFromSuperview]; 
} @end 

而且CustomizableNSView是：

#import <Cocoa/Cocoa.h> 

@interface CustomizableNSView : NSView 
{ 

} 
@property (nonatomic) NSRect boundsToCustomize; 
@property (nonatomic) CGFloat borderWidth; 
@property (nonatomic) CGFloat borderRadious; 
@property (nonatomic) NSColor *borderColor; 
@property (nonatomic) NSColor *backgroundColor; 


@end 
================= 
#import "CustomizableNSView.h" 

@implementation CustomizableNSView 


- (void)drawRect:(NSRect)dirtyRect { 

    [super drawRect:dirtyRect]; 
    NSRect r = self.bounds; 

    if(!NSIsEmptyRect(self.boundsToCustomize)) 
     r = self.boundsToCustomize; 
    if(self.borderColor){ 
     NSBezierPath * bgPath = [NSBezierPath bezierPathWithRoundedRect: r xRadius: self.borderRadious yRadius: self.borderRadious]; 
     bgPath.lineWidth = self.borderWidth; 
     NSAffineTransform * t = [NSAffineTransform transform]; 
     [t translateXBy: 0.5 yBy: 0.5]; 
     [bgPath transformUsingAffineTransform: t]; 
     //NSColor* rgbColor = [NSColor colorWithCalibratedRed:101.0/255.0 green: 101.0/255.0 blue:101.0/255.0 alpha:0.5]; 
     [self.borderColor set]; 
     [bgPath stroke]; 

     if(self.backgroundColor){ 
      [self.backgroundColor set]; 
      [bgPath fill]; 
     } 
    } 


} 
@end 

我希望这会帮助别人的同时将加快发展。