Sep 7, 2017 1 min read

Android Gotchas: #1 Setting a Drawable on a TextView programmatically

AG is a mini-series on the quirks and idiosyncrasies of Android app development.

Using the XML attribute

I’ve set many drawableLefts and drawableRights on TextViews over the last few years.

<TextView
    ...
    android:drawableLeft="@drawable/ic_viewer_count"/>

Boom. Nice and easy. Never had to set it programatically, yet.

Setting compound drawables

Well, it doesn’t work ¯\(ツ)/¯. After wasting an hour and pulling half my hair out, I noticed I had overlooked an important detail in the JavaDoc.

Sets the Drawables (if any) to appear to the left of, above, to the right of, and below the text... The Drawables must already have had Drawable.setBounds called.

Rescue time

Here’s how to do it right:

With IntrinsicBounds

viewerCount.setCompoundDrawablesWithIntrinsicBounds(id, null, null, null)

With DataBinding

@BindingAdapter("drawableLeft")
public static void setDrawableLeft(TextView view, int id) {
    view.setCompoundDrawablesWithIntrinsicBounds(id, null, null, null)
}

With a Kotlin Extension

fun TextView.setDrawableLeft(id: Int) {
    setCompoundDrawablesWithIntrinsicBounds(id, 0, 0, 0)
}

“The Drawable’s bounds will be set to its intrinsic bounds.”