几个经常需要自定义的组件：UIScrollview、UItextView、UIButton

分类： Iphone应用开发 2011-12-28 15:13 136人阅读 评论(0) 收藏 举报

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];

}

[plain] view plaincopy

//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];

}

使用方法

在所有者类中定义这些自定义的组件，如定义

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];

}