Android TextView partly gradient

Question

Android TextView partly gradient,

such as: "hello android hello kotlin", I want "kotlin" gradient, how can I do?

Answer 1

you can try like this programmatically using spannbleSting

    public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        TextView textView = findViewById(R.id.textView);
        String fullText = "hello android hello kotlin";
        String gradientText = "kotlin";

        // Find the starting index of the gradient text
        int startIndex = fullText.indexOf(gradientText);

        if (startIndex != -1) {
            SpannableString spannableString = new SpannableString(fullText);

            // Define the gradient color and other options
            int[] gradientColors = {0xFF0000FF, 0xFF00FF00}; // Example: Blue to Green
            Shader shader = new LinearGradient(0, 0, 0, textView.getTextSize(), gradientColors, null, Shader.TileMode.CLAMP);

            // Apply the gradient color span to the desired part of the text
            spannableString.setSpan(new ForegroundColorSpan(shader), startIndex, startIndex + gradientText.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);

            textView.setText(spannableString);
        }
    }
    private static class ForegroundColorSpanWithShader extends CharacterStyle implements UpdateAppearance {

    private Shader shader;

    ForegroundColorSpanWithShader(Shader shader) {
        this.shader = shader;
    }

    @Override
    public void updateDrawState(TextPaint tp) {
        tp.setShader(shader);
    }
}
}