Question

我可以绘制我的NSStrings，但是在绘制它时我无法调整大小。我的drawRect：方法是：

- (void)drawRect:(CGRect)rect
{

NSArray *objectArray = [NSArray arrayWithObjects:[UIFont systemFontOfSize:80.0f], nil];
NSArray *keyArray = [NSArray arrayWithObjects:@"NSFontAttributeName", nil];
NSMutableDictionary *textAttributes = [NSMutableDictionary dictionaryWithObjects:objectArray forKeys:keyArray];
NSString *myTestString = @"Test String";
[textAttributes setObject:[UIColor redColor] forKey:NSForegroundColorAttributeName];
[myTestString drawAtPoint:CGPointMake(20, 30) withAttributes:textAttributes];
[myTestString drawInRect:CGRectMake(50, 50, 500, 500) withAttributes:textAttributes];

NSLog(@"wrote %@ with %@", myTestString, textAttributes);
}

textAttributes看起来很好，字体信息返回为：

 NSFontAttributeName = "<UICTFont: 0x14eeff40> font-family: \".HelveticaNeueInterface-M3\"; font-weight: normal; font-style: normal; font-size: 80.00pt"

我可以使用attributes数组正确更改颜色，为什么这会导致文本默认为10pt大小？

Answer 1

NSAttributedString是你想要的。 UICatalog示例代码有一个NSAttributedString用法示例：

#pragma mark - UIPickerViewDataSource

- (NSAttributedString *)pickerView:(UIPickerView *)pickerView attributedTitleForRow:(NSInteger)row forComponent:(NSInteger)component
{
    NSMutableAttributedString *attrTitle = nil;

    // note: for the custom picker we use custom views instead of titles
    if (pickerView == self.myPickerView)
    {
        if (row == 0)
        {
            NSString *title;
            if (component == 0)
                title = [self.pickerViewArray objectAtIndex:row];
            else
                title = [[NSNumber numberWithInt:row] stringValue];

            // apply red text for normal state
            attrTitle = [[NSMutableAttributedString alloc] initWithString:title];
            [attrTitle addAttribute:NSForegroundColorAttributeName
                          value:[UIColor redColor]
                          range:NSMakeRange(0, [attrTitle length])];
        }
    }

    return attrTitle;
}

关于iOS的Stanford U MOOC课程（由Paul Hegarty和available on iTunes运行）概述了演讲4中NSAttributedString的使用。第5讲还介绍了您可以遵循的NSAttributedString代码演示。最后，github用户m2mtech发布了repositories of all code exercises and assignments for the course，您可以下载相关的项目文件here。

如何使用属性绘制NSString atPoint并调整SIZE？

1 个答案: