I put some strings in string.xml file as follows.

<string name="text1749">The <font color="#DE0010">book</font> was written by Mr. Martin Vikramasinghe.n<font color="#DE0010">පොත</font> ලිව්වේ මාටින් වික්‍රමසිංහ විසින්.</string>

The corresponding textview xml code is,

<TextView
                                android:id="@+id/id155"
                                android:layout_width="match_parent"
                                android:layout_height="wrap_content"
                                android:fontFamily="@font/iskpota"
                                android:gravity="start"
                                android:justificationMode="inter_word"
                                android:padding="15dp"
                                android:textColor="#000000"
                                android:textSize="20sp"
                                android:visibility="invisible"
                                app:autoSizeMaxTextSize="30sp"
                                app:autoSizeMinTextSize="10sp"
                                app:autoSizeStepGranularity="2sp"
                                app:autoSizeTextType="uniform"
                                android:background="@android:color/transparent"/>

Then I set “text1749” from string.xml file, to textview “@+id/id155” grammatically in activity as follows.

textview.setText(R.string.text1749);

When code runs I cant see the red color. Instead all string(“text1749”) is in black default.

Then tried chatgpt solutions,

TextView testTextView = findViewById(R.id.test_text_view);
String testHtml = "<font color='#FF0000'>Red Text</font> and <font color='#0000FF'>Blue Text</font>";
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
    testTextView.setText(Html.fromHtml(testHtml, Html.FROM_HTML_MODE_COMPACT));
} else {
    testTextView.setText(Html.fromHtml(testHtml));
}

Still no hope.

So If there is a correct way to do this pleas let me know.