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androidstringkotlintextviewstring.xml

How to format and style (Bold, TextSize) string resource in Android

enter image description here

Above is the image of what I want to achieve using String.xml

There are three things

  1. '76' & '20' will be replaced dynamically using String.format
  2. '20' should be bold
  3. '20' should be bigger in size

I have tried all the solutions using Html.fromHtml class.

Following are the solutions which I have tried. I am able to make '20' bold but couldn't make the '20' bigger in size.

Following are the differet variations of String.xml which I have tried

<string name="points_data">Use %1$d points= &lt;font size="30">₹ %2$d&lt;/font> in payment</string>

<string name="points_data">Use %1$d points= <font size="14"><b>₹ %2$d</b></font> in payment</string>

<string name="points_data">Use %1$d points= &lt;font size="14">&lt;b>₹ %2$d&lt;/b>&lt;/font> in payment</string>

<string name="points_data"><![CDATA[Use %1$d points= <font size="60"><b>₹ %2$d</b></font> in payment]]></string>

<string name="points_data">Use %1$d points= &lt;b>&lt;span style="fontSize='50'">₹ %2$d&lt;/span>&lt;/b> in payment</string>

Following is the method I use for parsing above string

val formattedText = String.format(getString(R.string.points_data), 76, 20)

textViewPoints.text = HtmlCompat.fromHtml(formattedText, HtmlCompat.FROM_HTML_MODE_LEGACY)

I have came across following links while googling for solution but none of them is working for my case.

  1. https://developer.android.com/guide/topics/resources/string-resource
  2. Set TextView style (bold or italic)
  3. Html.fromHtml deprecated in Android N

I have tried all the possible solutions which I could think of but none of them is working. I don't know what I am missing to implement. If anyone knows how to achieve this scenarion or knows about a way to achieve this please provide some guidance regarding that.

Solution

  • You don't need any html formatting, so you only need plain text in string resources, like this:

    <string name="points_data">Use %1$d points= ₹%2$d in payment</string>

    You can use a SpannableString, to format the 2nd parameter of your string resource.
    Both "%1$d" and "%2$d" will be just placeholders, so don't use String.format() in this case:

    val param1 = 20.toString()
val param2 = 70.toString()

var str = getString(R.string.points_data).replace("%1\$d", param1)
val index = str.indexOf("%2\$d")
val len = param2.length
str = str.replace("%2\$d", param2)

val sp = SpannableString(str)
sp.setSpan(StyleSpan(Typeface.BOLD), index, index + len, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE)
sp.setSpan(RelativeSizeSpan(1.5f), index, index + len, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE)

    Now if you want to set the text of a TextView:

    tv.text = sp

    The size of the text can be altered by changing 1.5f, which is relative to the original size.