Android Dimens Value calculation for different values folders

Question

I am giving size in dimen value for some UI components.My UI need to be supported by all devices in portrait mode so I put my dimen files into 16 folders

At first I inserted values in values-normal-xhdpi (as I have the device to test) .So now I have built my dimen file for values-normal-xhdpi folder.Now I am doing entries in values-normal-hdpi by again checking visual effect for normal-hdpi screen.This is really a hectic task I need some formula so that I can evaluate the value of dimens for remaining of folders.

Some of android standards says that drawable image should be in these ratio:

ldpi =0.75

mdpi =1.0

hdpi =1.5

xhdpi =2

but this is not working here as dimen value 100 dp for values-normal-mdpi is not give same effect as value 150 dp gives in values-normal-hdpi

My dimens.xml for values-normal-xhdpi

<resources>
    <!-- this is used in note -->
    <dimen name="text_size_h1">60sp</dimen>
    <dimen name="text_size_h2">50sp</dimen>
    <dimen name="text_size_h3">40sp</dimen>
    <dimen name="text_size_h4">30sp</dimen>
    <dimen name="text_size_h5">24sp</dimen>
    <dimen name="text_size_h6">20sp</dimen>

    <dimen name="text_size_h8">11sp</dimen>
    <dimen name="text_size_h10">10sp</dimen>
    <dimen name="text_size_h12">8sp</dimen>


    <dimen name="extra_mini">2dp</dimen>


    <dimen name="mini">4dp</dimen>
    <dimen name="x_mini">10dp</dimen>
    <dimen name="xx_mini">14dp</dimen>
    <dimen name="xxx_mini">20dp</dimen>

    <dimen name="mid">30dp</dimen>
    <dimen name="x_mid">40dp</dimen>
    <dimen name="xx_mid">50dp</dimen>
    <dimen name="xxx_mid">60dp</dimen>

    <dimen name="max">70dp</dimen>
    <dimen name="x_max">62dp</dimen>
    <dimen name="xx_max">90dp</dimen>
    <dimen name="xxx_max">100dp</dimen>

    <dimen name="supper">110dp</dimen>
    <dimen name="x_supper">120dp</dimen>
    <dimen name="xx_supper">130dp</dimen>
    <dimen name="xxx_supper">140dp</dimen>

    <dimen name="xxxxxx_supper">180dp</dimen>

    <dimen name="image_width">628dp</dimen>
    <dimen name="image_height">270dp</dimen>

</resources> 

Answer 1

"dp" are Density Independent Pixels. 100dp means 100px in mdpi, 150px in hdpi, 200px in xhdpi, &c.

This means that you do not need to specify values for each density variant if you always use dp (which is a good idea), they are converted automatically to pixels values for each one.

See http://developer.android.com/guide/practices/screens_support.html#terms

Density-independent pixel (dp)

A virtual pixel unit that you should use when defining UI layout, to express layout dimensions or position in a density-independent way. The density-independent pixel is equivalent to one physical pixel on a 160 dpi screen, which is the baseline density assumed by the system for a "medium" density screen. At runtime, the system transparently handles any scaling of the dp units, as necessary, based on the actual density of the screen in use.