macos - 单击 osx 10.6 选择 View

Question

我创建了一个 ImageView

for(int i=0; i<pcount; i++)
{
    int x = rand() % 350;
    int y = rand() % 350;
    NSRect rect = NSMakeRect((x+10),(y+10), 200, 200);
    //NSImageView *imageView 
    imageView1 = [[NSImageView alloc]initWithFrame:rect];
    [imageView1 setTag:i];

    // imageView = [[NSImageView alloc]initWithFrame:rect];
   // [imageView1 rotateByAngle:rand() % 150];

    [imageView1 setImageScaling:NSScaleToFit];
    [imageView1 canBecomeKeyView];
    NSImage *theImage = [[NSImage alloc]initWithContentsOfURL:(NSURL*)[patharray objectAtIndex:(i)]];
    [imageView1 setImage:theImage];
    [[imageView1 cell] setHighlighted:YES];
    [[layoutCustom view] addSubview:imageView1 positioned:NSWindowMovedEventType relativeTo:nil];}    

现在如何通过鼠标单击来选择每个 ImageView ？提前致谢。

Answer 1

我在这里假设您有不使用现有 Collection View 的原因。因此，从我在您的代码中读到的内容来看，您有layoutCustom.view，其中包含一堆 NSImageView。这里有两个选项:

1. 在您的layoutCustom对象中实现mouseDown:(或mouseUp:或两者)。将事件位置转换为 View 坐标并查找 CGRectContainsPoint(subview.frame, mouseDownPoint) 返回 YES 的任何 subview 。您应该选择该 View 。

2. 子类化 NSImageView 并实现 mouseDown:(或 mouseUp: 或两者)。在 mouseDown 上:只需设置一个“选定”标志即可。 View 可以在选择时自行绘制某些内容，或者layoutCustom对象可以观察属性并相应地绘制选择。

我更喜欢选项 1，因为它更简单，需要更少的类以及对象之间的交互更少。

// Option 1 (in layoutCustom class)

- (void) mouseDown:(NSEvent*)theEvent {
    CGPoint mouseDownPoint = [self convertPoint:theEvent.locationInWindow fromView:nil];
    for (NSView *view in self.subviews) {
        if (CGRectContainsPoint(view.frame, mouseDownPoint)) {
            // Do something to remember the selection.
            // Draw the selection in drawRect:
            [self setNeedsDisplay:YES];
        }
    }
}




// Option 2 (in Custom subclass of NSImage)

- (void) mouseDown:(NSEvent*)theEvent {
    self.selected = !self.selected;
}


// Option 2 (in layoutCustom class)
- (void) addSubview:(NSView*)view positioned:(NSWindowOrderingMode)place relativeTo:(NSView*)otherView {
    [super addSubview:view positioned:place relativeTo:otherView];
    [self startObservingSubview:view];
}

- (void) willRemoveSubview:(NSView*)view {
    [self stopObservingSubview:view];
}

- (void) startObservingSubview:(NSView*)view {
   // Register your KVO here
   // You MUST implement observeValueForKeyPath:ofObject:change:context:
}

- (void) stopObservingSubview:(NSView*)view {
   // Remove your KVO here
}