不用传context的dp 转 px工具

public class DisplayUtil {

static {
DisplayMetrics displayMetrics = Resources.getSystem().getDisplayMetrics();
density = displayMetrics.density;
scaledDensity = displayMetrics.scaledDensity;
}
private static float density;
private static float scaledDensity;

public static int px2dip(float px){
return (int) (px/density + 0.5f);
}

public static float dip2px(float dp){
return dp*density;
}
public static int px2sp(float px){
return (int) (px/scaledDensity + 0.5f);
}
public static float sp2px(float sp){
return sp*scaledDensity;
}
}