As we know Android coming with various device which having different Features, Resolution, and Screen-size so while developing an Application which support multiple (small and big) screen there is an obstacle of size and layout.
This leads to different combinations of screen sizes, resolutions, and DPIs and creates quite a challenge when designing and developing for Android devices. While some other Manufacturer (non Android) have different resolutions and DPI, they share the same screen size and the resolutions follow the same aspect ratio. Therefore, an image can be created to fit the non Android devices.
My question is that is there a proper flow or architecture that one should follow to meet the requirement?
Remember we do have Tablets of different Size and Resolution.
I'm aware that Android Developer contains this information but my view is from implementation.
From my knowledge what I understood is that for designing Android graphics even Programmer must know the designing concept.
Finally created a structure which handle layouts and icon for multiple screen.
Android generalises device displays into categories based on two parameters:
To determine screen size & density quickly, please install "What's my Size" app for Android.
Screen size
Android defines four generalised screen sizes:
Qualifier Size
small ~3 inches (approx)
normal ~4 inches (approx)
large Exceeds 4 inches
xlarge Exceeds 7 inches
Android defines four generalised screen densities:
Qualifier Description Nominal value
ldpi low density 120 ppi
mdpi medium density 160 ppi
hdpi high density 240 ppi
xhdpi extra high density 320 ppi
Typically:
It is listed here the percentage difference of device screen
But as we know now most of device coming with 480X800 so I'm consider this as based device, so our new calculation will like this
which means that first icon and design will be created for 480X800 only and then for rest ones(i.e. Ldpi, Mdpi, Xhdpi).
There are images which are common for all layout and must uniform in color and shape(no complex shape, no curve) so for this kind of image we are creating 9patch
which to be put in “drawable(no-suffix)” folder. To create 9Patch image you can either use DrawNinePatch or BetterNinePatch
Now just rename your images based on Android's standards and complete your application with hdpi
and then just take drawable-hdpi
folder and Open Adode Photoshop(recommended)
create Action of multiple size(just change the size according to percentage ratio) once Action created for all size then just do Batch Automate and give source(drawable-hdpi) and destination(drawable-ldpi, drawable-mdpi, drawable-xdpi).
The reason I insist you to use Photoshop because it will resize automatically your image with Actions and one more plus point is that you need not to rename the file(it will assign same name as original one).
once you completed with creation of all images, refresh your project and test it.
Sometimes there may be possibility that the layout which support screen(xhdpi, hdpi, mdpi) may be get cut in small screen(ldpi) so for handling this just create separate Layout folder(layout-small) for it and add ScrollView
(mostly). Thats it.
Tablet Tablets are categorized into two size.
In this we need to create image for both the screen and just put them accordingly
So all in all we will have this folder in our application to support multiple screen.
drawable
drawable-ldpi
drawable-mdpi
drawable-hdpi
drawable-xhdpi
drawable-large
drawable-xlarge
will be more qualifier combination with Screen size and Screen density
drawable-large-ldpi
drawable-large-mdpi
drawable-large-hdpi
drawable-large-xhdpi
more qualifier with Screen density and Version
drawable-ldpi-v11
drawable-mdpi-v11
drawable-hdpi-v11
drawable-xhdpi-v11
and more qualifier with Screen size and Version
drawable-large-v11
drawable-xlarge-v11
and more qualifier with Smallest width concept(SW)
drawable-sw???dp
Further more in Android V3.0 Honeycomb they introduced new concept of SW(smallest width)
in which device are categorized into screen width, so if we are creating a folder named drawable-sw360dp
then the device with 720dp(either width or height) will use resource from the this folder.
for example to find the Samsung Galaxy S3
dp to suffix to drawable-sw?dp
With reference of DP Calculation, If you want to support your layout or drawable to S3 then the calculation says
px= Device's width = 720
dpi= Device's density= 320
formula given
px = dp * (dpi / 160)
interchanging formula because we have px's value
dp = px / (dpi / 160)
now putting value,
dp= 720 / (320/160);
dp=360.
so drawable-sw360dp
will do the job
Get you Device configuaration from GsmArena Sameway you can also create folder according to Device's Android API version i.e. drawable-hdpi-v11` so the device which is having API11 and it is Hdpi then it will use this resources.
Additional Tips:
Use relative layouts, dp, sp, and mm
dp units - device independent pixels normalised to 1 physical pixel on a 160 ppi screen i.e. medium density. Scaled at runtime. Use for screen element dimensions
sp units - scaled pixels, specified as floating point values, based on dp units but additionally scaled for the user's font-size preference setting. Scaled at runtime. Use for font sizes
you should always use RelativeLayout for layouts; AbsoluteLayout is deprecated and should not be used.
Use appropriate image formats - PNG versus JPEG
Android "prefers" PNG for bitmap image files, "accepts" JPEG, and "discourages" GIF.
However, PNG and JPEG are not equivalents. They have different quality trade offs, and PNG is not always best:
JPEG can offer up to 50% file-size reductions over PNG, which is significant if your app is image-intensive
A higher quality "lossy" JPEG may look better than a highly compressed "lossless" PNG, for the same file size
Add labels to your images and graphics for debugging
Use the supports-screens element
Configure your emulators with real device values
Conventionally, desktop systems display at 72ppi (Mac), or 96ppi (Windows, Linux). Compared with mobile, desktop displays are always low density.
Always configure your Android emulators to mimic real device values, and always set them to scale to emulate device density.
In Eclipse, it's easy to create multiple emulators (from the Eclipse menu bar, select Window > AVD Manager > New) configured with values for real devices:
Name the emulator for the real device it's emulating Specify Resolution, don't use Built-in generic sizes Set the device density to match the real device (in the Hardware pane set Abstracted LCD Property to the real density, always an integer value)
When you launch the device, always select Scale display to real size, and type in the real screen dimension in inches.
If you don't set the device density, the emulator defaults to low density, and always loads ldpi-specific resources. Resolution (pixel dimensions) will be correct, but your density-dependent image resources will not display as intended.
Of course, nothing you do will reproduce higher density image quality on a lower density desktop display.
Here is the Data collected during a 7-day period ending on October 1, 2012. To see the latest statistic about Android platform version, go to here
Based on Screen Size
Based on Screen Density