减小第三行的 UIButton 标签字体大小

Question

我有一个可以更改文本的按钮。

如果按钮文本用于第三行，我希望它应该将其字体减少到 minimumScaleFactor。 我正在使用此代码

self.option1Button.titleLabel.minimumScaleFactor = .7;
self.option1Button.titleLabel.numberOfLines = 2;
self.option1Button.titleLabel.adjustsFontSizeToFitWidth = TRUE;

但这不起作用。当文本到达第三行时，它不会改变字体大小。

Answer 1

adjustToFit 仅适用于单行标签。

试试this:

//Create a string with the text we want to display.
self.ourText = @"This is your variable-length string. Assign it any way you want!";

/* This is where we define the ideal font that the Label wants to use.
Use the font you want to use and the largest font size you want to use. */
UIFont *font = [UIFont fontWithName:@"Marker Felt" size:28];

int i;
/* Time to calculate the needed font size.
This for loop starts at the largest font size, and decreases by two point sizes (i=i-2)
Until it either hits a size that will fit or hits the minimum size we want to allow (i > 10) */
for(i = 28; i > 10; i=i-2) {
    // Set the new font size.
    font = [font fontWithSize:i];
    // You can log the size you're trying: NSLog(@"Trying size: %u", i);

    /* This step is important: We make a constraint box 
    using only the fixed WIDTH of the UILabel. The height will
    be checked later. */ 
    CGSize constraintSize = CGSizeMake(260.0f, MAXFLOAT);

    // This step checks how tall the label would be with the desired font.
    CGSize labelSize = [self.ourText sizeWithFont:font constrainedToSize:constraintSize lineBreakMode:UILineBreakModeWordWrap];

    /* Here is where you use the height requirement!
    Set the value in the if statement to the height of your UILabel
    If the label fits into your required height, it will break the loop
    and use that font size. */
    if(labelSize.height <= 180.0f)
        break;
}
// You can see what size the function is using by outputting: NSLog(@"Best size is: %u", i);

// Set the UILabel's font to the newly adjusted font.
msg.font = font;

// Put the text into the UILabel outlet variable.
msg.text = self.ourText;

Answer 2

如果您希望按钮显示三行，则必须将 numberOfLines 设置为 3。奇怪但确实如此。