如何为MKAnnotation的字幕显示2行文本并更改右侧按钮的图像？

Question

我正在查看Apple的MapCallouts示例,用于地图注释和标注(==当您点击图钉时出现的气泡).每个注释都有坐标,标题和副标题.我想在2行显示字幕,我试过:

- (NSString *)subtitle
{
return @"Founded: June 29, 1776\nSecond line text";
}

但文本"第二行文字"保持在一行,使泡沫更宽.我明白了:

我还想将按钮的图像更改为我自己的图像,设置按钮的代码当前是这样的:

UIButton* rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];

有任何想法吗？

编辑:我尝试了7KV7的建议.按钮更改成功,但我仍然无法获得2行字幕.我的代码:

MKPinAnnotationView* customPinView = [[[MKPinAnnotationView alloc]
                                        initWithAnnotation:annotation reuseIdentifier:BridgeAnnotationIdentifier] autorelease];
        customPinView.pinColor = MKPinAnnotationColorPurple;
        customPinView.animatesDrop = YES;


        // Button
        UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
        button.frame = CGRectMake(0, 0, 23, 23);
        button.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;
        button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentCenter;

        //UIEdgeInsets titleInsets = UIEdgeInsetsMake(7.0, -20.0, 7.0, 7.0);
        //button.titleEdgeInsets = titleInsets;

        [button setImage:[UIImage imageNamed:@"ic_phone_default.png"] forState:UIControlStateNormal];
        //[button setImage:[UIImage imageNamed:@"ic_phone_selected.png"] forState:UIControlStateSelected];
        [button setImage:[UIImage imageNamed:@"ic_phone_selected.png"] forState:UIControlStateHighlighted];
        [button addTarget:self action:@selector(showDetails:) forControlEvents:UIControlEventTouchUpInside];

        customPinView.rightCalloutAccessoryView = button;

        //two labels
        UIView *leftCAV = [[UIView alloc] initWithFrame:CGRectMake(0,0,50,50)];
        //[leftCAV addSubview : button];
        UILabel *l1=[[UILabel alloc] init];
        l1.frame=CGRectMake(0, 15, 50, 50);
        l1.text=@"First line of subtitle"; 
        l1.font=[UIFont fontWithName:@"Arial Rounded MT Bold" size:(10.0)];

        UILabel *l2=[[UILabel alloc] init];
        l2.frame=CGRectMake(0, 30, 50, 50);
        l2.text=@"Second line of subtitle";
        l2.font=[UIFont fontWithName:@"Arial Rounded MT Bold" size:(10.0)];
        [leftCAV addSubview : l1];
        [leftCAV addSubview : l2];
        customPinView.leftCalloutAccessoryView = leftCAV;
        //customPinView.
        customPinView.canShowCallout = YES;

        return customPinView;

我明白了:

Answer 1

- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation
{   
    MKAnnotationView *annotationView = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:@"loc"];

    // Button
    UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
button.frame = CGRectMake(0, 0, 23, 23);
button.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;
button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentCenter;

[button setImage:[UIImage imageNamed:yourImageName] forState:UIControlStateNormal];
[advertButton addTarget:self action:@selector(buttonPress:) forControlEvents:UIControlEventTouchUpInside];

annView.rightCalloutAccessoryView = button;


    // Image and two labels
    UIView *leftCAV = [[UIView alloc] initWithFrame:CGRectMake(0,0,23,23)];
    [leftCAV addSubview : yourImageView];
    [leftCAV addSubview : yourFirstLabel];
    [leftCAV addSubview : yourSecondLabel];
    annotationView.leftCalloutAccessoryView = leftCAV;

    annotationView.canShowCallout = YES;

    return pin;
}

UPDATE

注释的默认样式仅支持标题和副标题.标题和副标题都不能包含换行符.没有子类化,你不能这样做.

要使用自定义视图,请查看Apple的示例代码:

http://developer.apple.com/library/ios/#samplecode/WeatherMap/Introduction/Intro.html

我也认为你的代码存在问题

UILabel *l1=[[UILabel alloc] init];
l1.frame=CGRectMake(0, 15, 50, 50);
l1.text=@"First line of subtitle"; 
l1.font=[UIFont fontWithName:@"Arial Rounded MT Bold" size:(10.0)];

UILabel *l2=[[UILabel alloc] init];
l2.frame=CGRectMake(0, 30, 50, 50);
l2.text=@"Second line of subtitle";
l2.font=[UIFont fontWithName:@"Arial Rounded MT Bold" size:(10.0)];
[leftCAV addSubview : l1];
[leftCAV addSubview : l2];

l1有一个框架(0,15,50,50),l2有(0,30,50,50).这两个不重叠吗？我的意思是l1将从y = 15开始,它的高度是50.所以当l2从30开始它可能重叠..你可以通过改变帧来检查

Answer 2

请使用这个

 - (MKAnnotationView *) mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation {

        if ([annotation isKindOfClass:[MKUserLocation class]])
            return nil;
        if ([annotation isKindOfClass:[CustomAnnotation class]]) {
            CustomAnnotation *customAnnotation = (CustomAnnotation *) annotation;

            MKAnnotationView *annotationView = [mapView dequeueReusableAnnotationViewWithIdentifier:@"CustomAnnotation"];

            if (annotationView == nil)
                annotationView = customAnnotation.annotationView;
            else
                annotationView.annotation = annotation;

            //Adding multiline subtitle code 

            UILabel *subTitlelbl = [[UILabel alloc]init];
            subTitlelbl.text = @"sri ganganagar this is my home twon.sri ganganagar this is my home twon.sri ganganagar this is my home twon.  ";

            annotationView.detailCalloutAccessoryView = subTitlelbl;

            NSLayoutConstraint *width = [NSLayoutConstraint constraintWithItem:subTitlelbl attribute:NSLayoutAttributeWidth relatedBy:NSLayoutRelationLessThanOrEqual toItem:nil attribute:NSLayoutAttributeNotAnAttribute multiplier:1 constant:150];

             NSLayoutConstraint *height = [NSLayoutConstraint constraintWithItem:subTitlelbl attribute:NSLayoutAttributeHeight relatedBy:NSLayoutRelationGreaterThanOrEqual toItem:nil attribute:NSLayoutAttributeNotAnAttribute multiplier:1 constant:0];
            [subTitlelbl setNumberOfLines:0];
            [subTitlelbl addConstraint:width];
            [subTitlelbl addConstraint:height];




            return annotationView;
        } else
            return nil;
    }