在UIView中画线

时间:2010-06-27 20:18:14

标签: ios iphone uiview

我需要在UIView中绘制一条水平线。什么是最简单的方法。例如,我想在y-coord = 200处绘制黑色水平线。

我不使用Interface Builder。

9 个答案:

答案 0 :(得分:309)

也许这有点晚了,但我想补充说有更好的方法。 使用UIView很简单,但相对较慢。此方法会覆盖视图如何绘制自身并且速度更快:

- (void)drawRect:(CGRect)rect {
    [super drawRect:rect];

    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetStrokeColorWithColor(context, [UIColor redColor].CGColor);

    // Draw them with a 2.0 stroke width so they are a bit more visible.
    CGContextSetLineWidth(context, 2.0f);

    CGContextMoveToPoint(context, 0.0f, 0.0f); //start at this point

    CGContextAddLineToPoint(context, 20.0f, 20.0f); //draw to this point

    // and now draw the Path!
    CGContextStrokePath(context);
}

答案 1 :(得分:120)

在您的情况下(水平线)最简单的方法是添加黑色背景颜色和框架[0, 200, 320, 1]的子视图。

代码示例(我希望没有错误 - 我没有Xcode写它):

UIView *lineView = [[UIView alloc] initWithFrame:CGRectMake(0, 200, self.view.bounds.size.width, 1)];
lineView.backgroundColor = [UIColor blackColor];
[self.view addSubview:lineView];
[lineView release];
// You might also keep a reference to this view 
// if you are about to change its coordinates.
// Just create a member and a property for this...

另一种方法是创建一个将在其drawRect方法中绘制一条线的类(您可以看到我的here的代码示例。)

答案 2 :(得分:22)

Swift 3和Swift 4

这就是你在视图结尾处画一条灰线的方法(与b123400的答案相同)

class CustomView: UIView {

    override func draw(_ rect: CGRect) {
        super.draw(rect)

        if let context = UIGraphicsGetCurrentContext() {
            context.setStrokeColor(UIColor.gray.cgColor)
            context.setLineWidth(1)
            context.move(to: CGPoint(x: 0, y: bounds.height))
            context.addLine(to: CGPoint(x: bounds.width, y: bounds.height))
            context.strokePath()
        }
    }
}

答案 3 :(得分:14)

只需添加不带文字和背景颜色的标签。 设置您选择的坐标以及高度和宽度。 您可以手动或使用Interface Builder进行操作。

答案 4 :(得分:11)

您可以为此使用UIBezierPath类:

可以根据需要绘制尽可能多的行:

我已经将UIView子类化了:

    @interface MyLineDrawingView()
    {
       NSMutableArray *pathArray;
       NSMutableDictionary *dict_path;
       CGPoint startPoint, endPoint;
    }

       @property (nonatomic,retain)   UIBezierPath *myPath;
    @end

并初始化将用于线条绘制的pathArray和dictPAth对象。我正在编写自己项目代码的主要部分:

- (void)drawRect:(CGRect)rect
{

    for(NSDictionary *_pathDict in pathArray)
    {
        [((UIColor *)[_pathDict valueForKey:@"color"]) setStroke]; // this method will choose the color from the receiver color object (in this case this object is :strokeColor)
        [[_pathDict valueForKey:@"path"] strokeWithBlendMode:kCGBlendModeNormal alpha:1.0];
    }

    [[dict_path objectForKey:@"color"] setStroke]; // this method will choose the color from the receiver color object (in this case this object is :strokeColor)
    [[dict_path objectForKey:@"path"] strokeWithBlendMode:kCGBlendModeNormal alpha:1.0];

}

touchesBegin方法:

UITouch *touch = [touches anyObject];
startPoint = [touch locationInView:self];
myPath=[[UIBezierPath alloc]init];
myPath.lineWidth = currentSliderValue*2;
dict_path = [[NSMutableDictionary alloc] init];

touchesMoved方法:

UITouch *touch = [touches anyObject];
endPoint = [touch locationInView:self];

 [myPath removeAllPoints];
        [dict_path removeAllObjects];// remove prev object in dict (this dict is used for current drawing, All past drawings are managed by pathArry)

    // actual drawing
    [myPath moveToPoint:startPoint];
    [myPath addLineToPoint:endPoint];

    [dict_path setValue:myPath forKey:@"path"];
    [dict_path setValue:strokeColor forKey:@"color"];

    //                NSDictionary *tempDict = [NSDictionary dictionaryWithDictionary:dict_path];
    //                [pathArray addObject:tempDict];
    //                [dict_path removeAllObjects];
    [self setNeedsDisplay];

touchesEnded方法:

        NSDictionary *tempDict = [NSDictionary dictionaryWithDictionary:dict_path];
        [pathArray addObject:tempDict];
        [dict_path removeAllObjects];
        [self setNeedsDisplay];

答案 5 :(得分:11)

另一种(甚至更短)的可能性。如果您在drawRect中,请执行以下操作:

[[UIColor blackColor] setFill];
UIRectFill((CGRect){0,200,rect.size.width,1});

答案 6 :(得分:1)

斯威夫特 3、4、5

这是我能找到的最简单的...

let lineView = UIView(frame: CGRect(x: 4, y: 50, width: self.view.frame.width, height: 1))
lineView.backgroundColor = .lightGray
self.view.addSubview(lineView)

答案 7 :(得分:0)

根据Guy Daher的回答。

我尽量避免使用?因为如果GetCurrentContext()返回nil。它会导致应用程序崩溃。

我会检查是否声明:

class CustomView: UIView 
{    
    override func draw(_ rect: CGRect) 
    {
        super.draw(rect)
        if let context = UIGraphicsGetCurrentContext()
        {
            context.setStrokeColor(UIColor.gray.cgColor)
            context.setLineWidth(1)
            context.move(to: CGPoint(x: 0, y: bounds.height))
            context.addLine(to: CGPoint(x: bounds.width, y: bounds.height))
            context.strokePath()
        }
    }
}

答案 8 :(得分:-1)

添加不带文字的标签和背景颜色相应的框架尺寸(例如:高度= 1)。通过代码或界面构建器来完成。