Question

Is there a pure-java way of setting the android:button attribute? My use case is I have some radio buttons with custom on/off images. They are currently in xml, but for several reasons I want their creation to be done in pure java. Currently the android:button references a <selector> xml file:

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_checked="true"
        android:drawable="@drawable/red_down_full" />
    <item android:drawable="@drawable/red_down" /> 
</selector>

Is there any way to either

• reference the <selector> xml file in java
• skip the <selector> entirely and just set the state_checked image in java?

Answer 1

Yes, you can set the xml image selector via code. If you want to set the selector on your RadioButton you have to call its setButtonDrawable(idOfYourSelector).

The code will be like this:

((RadioButton)findViewById(R.id.yourRadioButton)).setButtonDrawable(R.drawable.yourSelector);

If you want to set only the image you used for state_checked, then you need to supply the id of your state_checked image on setButtonDrawable(idOfYourImage) instead the id of your selector. In your case it will be:

((RadioButton)findViewById(R.id.yourRadioButton)).setButtonDrawable(R.drawable.red_down_full);

To ensure that it will not overlap the label of your RadioButton, you have to know the width of your drawable. Then set the left padding of your RadioButton depending on the width of your drawable. This will ensure the image for your RadioButton will not overlap its label.