Override method (append to other methods) in this class from another java class

Question

I want to set ClickableSpan for a TextView from another class. In ClickableSpan I need to override two methods, updateDrawState() and onClick(). The former method is the same for all TextViews, but the latter, onClick(), is different for any TextView. So I want write updateDrawState() method only once (in the Commons class), not for any TextView. How can I achieve this?

The following code blocks clearly explain what I want:

public class Commons {
    ...
    public void makeSpannable(TextView tv, String text, int startIndex, int endIndex, ClickableSpan appendClickableSpan) {
        SpannableString span = new SpannableString(text);
        span.setSpan({
        @Override
        public void updateDrawState(TextPaint ds) {
            ds.setColor(ContextCompat.getColor(Activation.this, R.color.textViewClickable));
            ds.setUnderlineText(false);

            appendClickableSpan;

        }}, startIndex, endIndex, 0);
        tv.setMovementMethod(LinkMovementMethod.getInstance());
        tv.setText(span, TextView.BufferType.SPANNABLE);
    }
    ...
}

and

public class Main {
    ...
    TextView textView = findViewById(R.id.textView1);
    String text = "some sample text";
    new Commons().makeSpannable(textView, text, 2, 6, new ClickableSpan() {
        @Override
        public void onClick(View widget) {
            if (validator.checkValidation(tilCode)) ResendActivationEmail();
        }
    });
    ...
}

Answer 1

I am not sure, if I understand you correctly, but you probably want to create common implementation of updateDrawState method and several of onClick.

You could achive this by making abstract class where you extends ClickableSpan and only implement updateDrawState like this:

public abstract class MyClickableSpan extends ClickableSpan {
    @Override
    public void updateDrawState(TextPaint ds) {
        // Your custom implementation
    }
}

And then use it like this:

ClickableSpan clickableSpan = new MyClickableSpan() {
    @Override
    public void onClick(View widget) {
        // Your custom implementation
    }
};

---

If you insist on Commons class, I probably make the method static:

public class Commons {
    public static void makeTextViewSpannable(TextView tv, String text, int startIndex, int endIndex, MyClickableSpan span) {
        SpannableString spannableString = new SpannableString(text);
        spannableString.setSpan(span, startIndex, endIndex, 0);
        tv.setMovementMethod(LinkMovementMethod.getInstance());
        tv.setText(spannableString, TextView.BufferType.SPANNABLE);
    }
}

Usage:

Commons.makeTextViewSpannable(textView, text, startIndex, endIndex, new MyClickableSpan() {
    @Override
    public void onClick(View widget) {
        // Your custom implementation
    }
});