can I know what is the difference between lineHeight and lineSpacingExtra in android xml. I tried to compare both, but I got the different result (I need the lineHeight function, however it is only supported in API 28).
Here is part of my code:
left:
android:textSize="14sp"
android:lineSpacingExtra="6dp"
right:
android:textSize="14sp"
android:lineHeight="20dp"
Result:
Any solution for this? Thank you.
You mentioned you want to set lineHeight in pre-API 28, an alternative approach would be to just set a small lineSpacingExtra / lineSpacingMultiplier value (as you have shown). Otherwise, there are many solutions to setting a line height yourself in this related question.
I'll briefly cover the differences below, with my summary and the official documentation.
android:lineHeight is the total height of each line. This includes the text, as well as any padding on the top and bottom.
Explicit height between lines of text. If set, this will override the values set for lineSpacingExtra and lineSpacingMultiplier.
android:lineSpacingExtra is the additional spacing added after each line of text (except the last one).
Extra spacing between lines of text. The value will not be applied for the last line of text.
Finally, you may be interested in android:lineSpacingMultiplier. This is similar to lineSpacingExtra, but with a multiplier value of the current height (e.g. 1.2) instead of a fixed value.
Extra spacing between lines of text, as a multiplier. The value will not be applied for the last line of text.
Further information (besides the included quotas) is available in the TextView documentation.
MaterialTextView (MTV) includes the ability to set the android:lineHeight.
And if you use the app: prefix, it is backwards compatible until SDK-Version 21.
Btw., under some circumstances (i believe its depending on your style, but am not sure about it), standard TextViews are automatically replaced with MTVs. (Check your LayoutInspector, you might already use them without knowing it)
In case you're still wondering about the differences, there's an excellent talk by the android team about text in general; which should solve your question at ~16:50.
android:lineHeight defines Explicit height between lines of text. while android:lineSpacingExtra defines Extra spacing between lines of text you can read more android_documentation_for_text_arributes
android:lineHeight
is used to specify the total height for single line of text.
android:lineSpacingExtra
is used to add extra spacing between 2 lines of text in addition to the default line height used by android.
In order to replicate lineHeight functionality with API level < 28, set the lineSpacingMultiplier to 0 and set the lineSpacingExtra to the lineHeight that you want to use
android:lineSpacingMultiplier="0"
android:lineSpacingExtra="<enter line height value here in dp>"