Android Custom keyboard , The following classes could not be instantiated:

Question

I have created a custom keyboard for my app. You can see the code for my keyboard below. I am getting error in xml viewer Similar question has been asked Android - Unsuppo

Answer 1

See this question and answers: Android - Unsupported Service: audio

In short: It is bug of android source. But I found solution how fix it.

Use KeyboardViewFix as replace KeyboardView:

public class KeyboardViewFix extends KeyboardView {
    public static boolean inEditMode = true;

    @TargetApi(21) // Build.VERSION_CODES.L
    public KeyboardViewFix(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(inEditMode ? new ContextWrapperInner(context) : context, attrs, defStyleAttr, defStyleRes);
    }

    public KeyboardViewFix(Context context, AttributeSet attrs, int defStyleAttr) {
        super(inEditMode ? new ContextWrapperInner(context) : context, attrs, defStyleAttr);
    }

    public KeyboardViewFix(Context context, AttributeSet attrs) {
        super(inEditMode ? new ContextWrapperInner(context) : context, attrs);
    }

    public static class ContextWrapperInner extends ContextWrapper {
        Context base;
        public ContextWrapperInner(Context base) {
            super(base);
            this.base = base;
        }
        public Object getSystemService(String name) {
            return Context.AUDIO_SERVICE.equals(name) ? null : base.getSystemService(name);
        }       
    }
}

One note: On start your app, before any other code you need set KeyboardViewFix.inEditMode = false; or you can get some errors.