how to change textView color when scrolled on same color background?

Question

I have a textView that its color is white, but when I scroll this textView it comes to be above an imageView with the same color. if I scrolled the textView and it entered that range of the dark image view, the text will not appear as its color is the same as the imageView, I want to change textView color when it gets above the imageView

Answer 1

I used ScrollView like you did and retrieved the Y coordinates inside addOnScrollChangedListener Upon reaching a specific number in Y coordinates, I will change the font color I want, and on return to the original coordinates, return the original color to him.

    //Definition of Object

    ScrollView scrollView ;
    TextView textView ;

      scrollView = findViewById(R.id.scrollView);
      textView = findViewById(R.id.tx);

Use getViewTreeObserver() method of your ScrollView . here is an example:

    scrollView.getViewTreeObserver().addOnScrollChangedListener(new ViewTreeObserver.OnScrollChangedListener() {
        @Override
        public void onScrollChanged() {

            int scrollY = scrollView.getScrollY(); // vertical scroll position
            int scrollX = scrollView.getScrollX(); // horizontal scroll position

            if (scrollY <= 100 || scrollY == 150)
                textView.setTextColor(ContextCompat.getColor(getApplicationContext(), R.color.blue));

            else if (scrollY >= 151)
                textView.setTextColor(ContextCompat.getColor(getApplicationContext(), R.color.red));

        }
    });

Note: These numbers are only available in the comparison for clarity of example. You can change them according to your need.

Answer 2

This is not the exact answer to your question, but maybe a solution for your problem.

A white background with 50% transparency to your TextView. That way it will look the same in the white section and and it would make the text readable in the blue section.