几个经常需要自定义的View总结
为了独立出组件的一些功能，如，为UIbutton切换背景图片，我们经常需要自定义一些组件，下面是我经常用到的，先总结出来，以后会慢慢更新：
－：UIScroview
srollview的事件经常与其子view事件冲突，截断子view事件的相应
//传递touch事件
- (void)touchesBegan:(NSSet*)touches withEvent:(UIEvent*)event
{
if(!self.dragging)
{
[[selfnextResponder]touchesBegan:toucheswithEvent:event];
}
[supertouchesBegan:touches withEvent:event];
// NSLog(@"MyScrollView touch Began");
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
if(!self.dragging)
{
[[selfnextResponder]touchesMoved:toucheswithEvent:event];
}
[supertouchesMoved:touches withEvent:event];
}
- (void)touchesEnded:(NSSet*)touches withEvent:(UIEvent*)event
{
if(!self.dragging)
{
[[selfnextResponder]touchesEnded:toucheswithEvent:event];
}
[supertouchesEnded:touches withEvent:event];
}
//父视图是否可以将消息传递给子视图，yes是将事件传递给子视图，则不滚动，no是不传递则继续滚动
- (BOOL)touchesShouldBegin:(NSSet *)touches withEvent:(UIEvent *)event inContentView:(UIView *)view
{
if ([view isKindOfClass:[CustomUITextViewclass]])
{
return YES;
}
else
{
returnNO;
}
}
//Yes是子视图取消继续接受touch消息（可以滚动），NO是子视图可以继续接受touch事件（不滚动）
//默认的情况下当view不是一个UIControlo类的时候，值是yes,否则是no
//调用情况是这样的一般是在发送tracking messages消息后会调用这个函数，来判断scroll是否滚动，还是接受子视图的touch事件
- (BOOL)touchesShouldCancelInContentView:(UIView *)view
{
NSLog(@"用户点击的视图 %@",view);
returnNO;
}
二：UITextView默认是没有边框的，可以给它加个凹下去的边框
-(void) drawRect:(CGRect)rect {
[self.layersetBackgroundColor: [[UIColorwhiteColor]CGColor]];
[self.layersetBorderColor: [[UIColorgrayColor]CGColor]];
[self.layersetBorderWidth:1.0];
[self.layersetCornerRadius:8.0f];
[self.layersetMasksToBounds:YES];
UIGraphicsBeginImageContext(self.frame.size);
CGContextRef currentContext =UIGraphicsGetCurrentContext();
CGContextSetLineWidth(currentContext, 2.0);
CGContextSetRGBStrokeColor(currentContext, 0.6,0.6,.6, 1.0);
CGRect myRect = CGContextGetClipBoundingBox(currentContext);
float myShadowColorValues[] = {0,0,0,1};
CGColorSpaceRef myColorSpace =CGColorSpaceCreateDeviceRGB();
CGColorRef colorRef = CGColorCreate(myColorSpace, myShadowColorValues);
CGContextSetShadowWithColor(currentContext, CGSizeMake(-1,1),2, colorRef);
CGContextStrokeRect(currentContext, myRect);
UIImage *backgroundImage = (UIImage *)UIGraphicsGetImageFromCurrentImageContext();
UIImageView *myImageView = [[UIImageViewalloc]initWithFrame:CGRectMake(0,0,self.frame.size.width,self.frame.size.height)];
[myImageView setImage:backgroundImage];
[selfaddSubview:myImageView];
[myImageView release];
UIGraphicsEndImageContext();
}
三：我们会想按下按钮时，切换button的图片背景，可以给UIbutton加个UIControllEvent事件的消息通知，当按钮被按下的时候，通知按钮所有者去切换图片
- (id)initWithFrame:(CGRect)_frame {
if (self = [superinitWithFrame:_frame]) {
[selfaddTarget:selfaction:@selector(touchDown:)forControlEvents:UIControlEventTouchDown];
[selfaddTarget:selfaction:@selector(touchUpInside:)forControlEvents:UIControlEventTouchUpInside];
//[selfaddTarget:selfaction:@selector(touchUpOutside:)forControlEvents:UIControlEventTouchUpOutside];
}
returnself;
}
- (void)touchDown:(id)sender {
NSNotification *notification = [NSNotificationnotificationWithName:@"TouchDownButton"object:selfuserInfo:nil];
[[NSNotificationCenterdefaultCenter]postNotification:notification];
NSLog(@"%s",__FUNCTION__);
}
- (void)touchUpInside:(id)sender {
//[self setBackgroundImage:@"next.png" forState:UIControlStateNormal];
NSNotification *notification = [NSNotificationnotificationWithName:@"TouchUpButton"object:selfuserInfo:nil];
[[NSNotificationCenterdefaultCenter]postNotification:notification];
}
CustomerButton *nextButton;
监听消息
[notification addObserver:self selector:@selector(touchDownNext) name:@"TouchDownButton" object:nil];
[notification addObserver:self selector:@selector(touchUpNext) name:@"TouchUpButton" object:nil];
监听到后需要执行的动作
-(void)touchDownNext{
UIImage *image = [UIImageimageNamed:@"next_pressed.png"];
[nextButtonsetBackgroundImage:imageforState:UIControlStateHighlighted];
}
-(void)touchUpNext{
UIImage *image = [UIImageimageNamed:@"next.png"];
[nextButtonsetBackgroundImage:imageforState:UIControlStateNormal];
}