希望在按钮上创建一个翻转效果,我创建了一个名为Button的NSButton子类.
Button.h：
#import <AppKit/AppKit.h>
@interface Button : NSButton {
}
- (void)mouseEntered:(NSEvent *)theEvent;
- (void)mouseExited:(NSEvent *)theEvent;
- (void)mouseDown:(NSEvent *)ev;
- (void)mouseUp:(NSEvent *)theEvent;
@end
Button.m：
#import“Button.h”
@implementation Button
- (id)initWithFrame:(NSRect)frameRect {
self = [super initWithFrame:frameRect];
if(self != nil) {
NSLog(@"btn init");
}
return self;
}
- (void)mouseEntered:(NSEvent *)theEvent{
NSLog(@"mouseEntered");
[self setImage:[NSImage imageNamed:@"lockIcon_2.png"]];
[self setNeedsDisplay];
}
- (void)mouseExited:(NSEvent *)theEvent{
[self setImage:[NSImage imageNamed:@"lockIcon_1.png"]];
NSLog(@"mouseExited");
[self setNeedsDisplay];
}
- (void)mouseDown:(NSEvent *)ev {
NSLog(@"mouseDown!");
}
- (void)mouseUp:(NSEvent *)ev {
NSLog(@"mouseUp!");
}
@end
有了上面的代码,每次点击一个按钮,我都会在日志中看到“mouseDown”,但是我看不到“mouseEntered”和“mouseExited”(当然看不到图像的变化)？可悲的是,我知道我错过了一些明显的东西,但我只是没有看到它？
解决方法
问题是NSButton只有在您将自定义NSTrackingArea添加到按钮时才能处理某些鼠标事件.
尝试在你的按钮类中添加这个代码.它帮了我如果他们不满意你也可以选择选项.
- (void)createTrackingArea
{
NSTrackingAreaOptions focusTrackingAreaOptions = NSTrackingActiveInActiveApp;
focusTrackingAreaOptions |= NSTrackingMouseEnteredAndExited;
focusTrackingAreaOptions |= NSTrackingAssumeInside;
focusTrackingAreaOptions |= NSTrackingInVisibleRect;
NSTrackingArea *focusTrackingArea = [[NSTrackingArea alloc] initWithRect:NSZeroRect
options:focusTrackingAreaOptions owner:self userInfo:nil];
[self addTrackingArea:focusTrackingArea];
}
- (void)awakeFromNib
{
[self createTrackingArea];
}
希望它有帮助.
