像素 转换 px dp
public static int dip2px(Context context, float dpValue){
final float scale = context.getResources().getDisplayMetrics().density;
return (int)(dpValue * scale + 0.5f);
}
public static int px2dip(Context context, float pxValue){
final float scale = context.getResources().getDisplayMetrics().density;
return (int)(pxValue / scale + 0.5f);
}