Question

I have a TextView to be used as a bluetooth connection console. When I send a command, I want it to be written in a color (for example cyan), and the answers received in a different color (for example red).

Is it possible to do that, and if so, how?

I read it may be possible to do using HTML, but i’m not quite sure it is the best approach, or even how to do it.

Answer 1

Do you really need it to be a TextView or can you use a ListView instead and add a new row in the list for each command/answer?

If you really want to use a TextView you can do something like this (This is a working example you can just copy and paste to your app to try out):

package com.c0deattack;

import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.text.Spannable;
import android.text.style.ForegroundColorSpan;
import android.widget.LinearLayout;
import android.widget.TextView;

public class MultipleColoursInOneTextViewActivity extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        TextView tv = new TextView(this);

        String command = "This is a command";
        String response = "\nThis is a response";

        tv.append(command + response);
        Spannable spannableText = (Spannable) tv.getText();
        spannableText.setSpan(new ForegroundColorSpan(Color.GREEN), 0, command.length(), 0);
        spannableText.setSpan(new ForegroundColorSpan(Color.RED), command.length(), command.length() + response.length(), 0);

        LinearLayout layout = new LinearLayout(this);
        layout.addView(tv);
        setContentView(layout);
    }
}

So that shows that it can be done, but you’ll obviously notice you’ll have to set the line breaks yourself and workout where each command/answer starts and ends so you can apply the correct colour to it. It’s not that hard but to me, feels clunky.