使用CGContext绘制线条 [英] Draw Line using CGContext

问题描述

我想在表格视图单元格中绘制线条，以便我可以放置textfield&切换到单个单元格。我增加了细胞的高度。我怎样才能在细胞中划线？

I want to draw line in table view cell so that I can place textfield & switch in single cell. I increased the height of cell. How can I draw line in cell?

我有UIView的子类，其中包含以下代码

I have subclass of UIView which contains following code

 //Get the CGContext from this view
 CGContextRef context = UIGraphicsGetCurrentContext();
 //Set the stroke (pen) color
 CGContextSetStrokeColorWithColor(context, [UIColor redColor].CGColor);
 //Set the width of the pen mark
 CGContextSetLineWidth(context, 1.0);

 // Draw a line
 //Start at this point
 CGContextMoveToPoint(context, 10.0, 30.0);

 //Give instructions to the CGContext
 //(move "pen" around the screen)
 CGContextAddLineToPoint(context, 310.0, 30.0);


 //Draw it
 CGContextStrokePath(context);

然后我有一个tableViewController，带有分组表样式。在cellForRowAtIndexPath中我有以下代码

Then I have a tableViewController with grouped table style. In cellForRowAtIndexPath I have following code

//code to add textfield
DrawLineView *drawLine = [[DrawLineView alloc]init];
[cell addSubview:drawLine];
//code add switch

但它没有绘制任何行。我不能使用2个不同的细胞。我得帮助我。这是我第一次处理iphone的图形。谢谢

But it is not drawing any line. I can't use 2 different cells. I have to Please help me. This is my first to deal with graphics i iphone. Thanks

推荐答案

两件事......
首先，你通常不会自己进入细胞。

Two things... First, you usually don't draw into the cell itself.

您通常会进入内容视图。有时它有意义绘制到单元格的backgroundView或selectedBackgroundView。

You normally draw into the content view. Sometimes it makes sense draw into the cell's backgroundView or selectedBackgroundView.

[cell.contentView addSubview:drawLine];

其次，默认的单元格文本标签cell.textLabel和cell.detailTextLabel具有非透明背景。尝试将其背景颜色设置为 [UIColor clearColor] 。

Second, the default cell text labels cell.textLabel and cell.detailTextLabel have non-transparent background. Try setting their background colors to [UIColor clearColor].

编辑：还有一件事：你需要设置一个drawLine的正确框架

one more thing: you need to set a proper frame for your drawLine

DrawLineView *drawLine = [[DrawLineView alloc]initWithFrame:cell.contentView.bounds];

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