[안드로이드/java] BottomSheet 스크롤 할 때 slideOffset 으로 background 조절

int colorFromTop = getResources().getColor(R.color.downy); 
int colorFromBottom = getResources().getColor(R.color.scooter); 
int colorTo = getResources().getColor(R.color.transparent);  
int[] colors = {interpolateColor(slideOffset, colorFromTop, colorTo), interpolateColor(slideOffset, colorFromBottom, colorTo)}; 
GradientDrawable gd = new GradientDrawable(GradientDrawable.Orientation.TOP_BOTTOM, colors); 
gd.setCornerRadii(new float[]{radius, radius, radius, radius, 0, 0, 0, 0});
act.layoutIntroPeek.setBackground(gd);

 

background 가 gradient 도 있고 상단 corner도 있어서 작업하였다.

 

 

 

참조한 코드

https://android.jlelse.eu/choreographic-animations-with-androids-bottomsheet-fef06e6ecb81

Choreographic animations with Android’s BottomSheet

private int interpolateColor(float fraction, int startValue, int endValue) {   
	int startA = (startValue >> 24) & 0xff;   
    int startR = (startValue >> 16) & 0xff;   
    int startG = (startValue >> 8) & 0xff;   
    int startB = startValue & 0xff;   
    
    int endA = (endValue >> 24) & 0xff;   
    int endR = (endValue >> 16) & 0xff;   
    int endG = (endValue >> 8) & 0xff;   
    int endB = endValue & 0xff;   
    
    return ((startA + (int) (fraction * (endA - startA))) << 24) |   
    	((startR + (int) (fraction * (endR - startR))) << 16) |   
        ((startG + (int) (fraction * (endG - startG))) << 8) |   
        ((startB + (int) (fraction * (endB - startB)))); 
}