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Supporting multiple screen size - Android

I am going to develop new application in Android. This application should only work in portrait (even for tablet). Also the UI and layout design should be similar on phones and tablet. We can't change the layout design for tablet as it has huge area to use. We have to stretch all the images to match phones. We can use nine patch. But I am little bit confused of using images in multiple drawables.
As per my analysis (may be wrong.. : ) ) the screens are divided into density and sizes. We can use the scaling ratio of 3:4:6:8. But this ratio is based on the density. But in my case I have to stretch the entire UI to fill the Tablet screen.
So what are the drawables that can be used for a app like this which can support multiple devices. And what are the screen sizes for which we have to design.
And this application needs nearly 100 layouts. So I am planning to maintain single layout and designing the layout using weight for each layout instead of using dimension.
Also if I used multiple APKs to support different screen size what are the drawables used to support
1. Small and Normal
2. Large
3. Xlarge

I just did something very similar. To stretch the app without creating new layouts I used dimensions set in XML
res/values/dimensions.xml
res/values-sw600dp/dimensions.xml -> 7+ inches
res/values-sw720dp/dimensions.xml -> 10+ inches
Dimensions are resources files:
<dimen name="default_padding">11dp</dimen>
You can increase the dimensions by about 30% in the 600 and 720 file.
Then simply used #dimen/default_padding in your layout and it will be scaled
Regarding images, either you make sure you have all your assets in all densities, or you set fixed size to you ImageView's and appropriate scaleType

Firstly, you do NOT want to create multiple APKs to support multiple screen densities. Android provides all of the framework you need to support everything within one build, you just need to create the right resource hierarchy drawables with your desired densities.
So what exactly do you need... based on your question the following:
portrait mode: you can specify this in each Activity declared in your AndroidManifest file using the following:
<activity android:name=".MainActivity"
android:label="#string/app_name"
android:configChanges="orientation" >
...
</activity>
NOTE: Per the Android docs, if you're targeting API >= 13, and you use the android:configChanges attribute you should also use the android:screenSize attribute to help specify size changes.
dimension sizes for various screens: as touched upon, this can also be handled in resources. This is your best way to use one common layout file but configure the layout for use on numerous devices. See http://developer.android.com/guide/topics/resources/more-resources.html#Dimension for how to use dimensions if you're unfamiliar
drawables: it sounds like this is the crux of your question. As you mentioned, using nine-patches will help you reduce your app footprint and fill in extra space (see here and here for more on nine-patches). The sizes you should support and the densities needed for those sizes are discussed in great detail in Android design docs, so much detail I could not even do it justice rehashing it here. I've provided links below to as many places as I could remember that this is discussed.
Good luck!
Here are links to Android design docs that you will find useful (some of which have been mentioned):
http://developer.android.com/guide/topics/resources/providing-resources.html#AlternativeResources
http://developer.android.com/training/multiscreen/index.html
http://developer.android.com/guide/practices/screens_support.html
http://developer.android.com/design/style/devices-displays.html

In addition to the pixel density specific folders, you can specify screen-size specific folders
drawable/
drawable-large/
drawable-xlarge/
drawable-hdpi/
drawable-large-hdpi/
drawable-xlarge-hdpi/
drawable-xhdpi/
drawable-large-xhdpi/
drawable-xlarge-xhdpi/
So you could design scale appropriate graphics for the various screen sizes and densities. Please note that a give screen size category (e.g. "large") will only give you a rough idea as to the actual device pixel dimensions of the device, but you'll get good guidelines for min/max dp ranges.
For example, you might have a 100x100 image you want to display on phones (screen size "normal"), you'd create image assets at 100x100, 150x150, 200x200 for drawable, drawable-hdpi, drawable-xhdpi folders respectively. But on 7" tablets, i.e. "large" screen size devices, you might display this same image at 200x200, so your "drawable-large" folder assets would be 200x200, 300x300, 400x400, and on 10" tablets, i.e. "xlarge" screens, you might display the same image at 300x300, 450x450, 600x600, so these go in "drawable-xlarge-*" folders.
All the details are here:
http://developer.android.com/guide/practices/screens_support.html

First you need all the possible screen layouts
drawable
drawable-ldpi
drawable-mdpi
drawable-hdpi
drawable-xhdpi
drawable-xxhdpi // phones like s4
drawable-xlarge
drawable-tvdpi // nexus 7 etc
drawable-xlarge-xhdpi //tablet like nexus 10
layout : for phone
layout-sw600dp
layout-sw720dp
then you need to put all use 9- patch images for buttons etc ... you can also make your custom drawable it would be easy and handy to work on ..Also you can take dpi for each screen by using switch and scale it the layout accordingly.
As, in one of my project I had used this technique for showing respective thing to each resolution device .
DisplayMetrics metrics = getResources().getDisplayMetrics();
int densityDpi = (int) metrics.density ;
switch (densityDpi) {
case (int) 1.5:
break;
case (int) 2: //1.75 will be 2 in INT.
break;
default:
break;
}
also keep all the values you are going to used for margin padding etc values-sw600dp for tvdpi tablet ,value-sw720dp for tablets
Last but not least keep all thing generic as much as you can and put it in drawable ..
I have seen some ppl who used background patterns of different dpi's and put it in respective drawable .. if there is such thing like pattern make your custom drawble and repeat it accordingly
that will save your time .. hope it may help you

In order to stretch all the images to match phones you can specify the image size using the sdp size unit. This size unit is relative to the screen size so it can fulfill your requirement.

Background images for different screens

In my application I have a background for activity. This is an image, I am going to use fitXY for it. I am ok if it will be resized a little (keeping aspect ration is not very important) but not very much.
I am going to prepare few images with different size and for both Portrait and Landscape orientation. I am going to cover about 90% of devices.
My question is the following:
What images sizes I need for background?
What folders under "res" I should put these images?
I would like to get very specific file sizes and folder name where to put these files.
The solution should work on tablets as well.

I just used two images with maximum sizes (one portrait and one landscape). Then android resized the to smaller and it looks quite good for me.
I have one background with resolution: 800*1200 px in drawable folder
and another with resolution: 1200*800 px in drawable-land folder
This works pretty fine on tablets.

You have to create multiple resources for your app. Android has 4 resolutions (ldpi,mdpi,hdpi and xhdpi) and 4 generalized screen sizes (small, medium, large and extra large). So you have to make 4 layouts (or 3 if you don't plan on supporting tablets, since tablets come under the extra large category) to support the screen sizes.
Here's a general guide:
put layouts for small, medium, large and extra large in your res/ folder as follows:
res/layout/sample_layout.xml // default layout
res/layout-small/sample_layout.xml // layout for small screen size
res/layout-large/sample_layout.xml // layout for large screen size
res/layout-xlarge/sample_layout.xml // layout for extra large screen size
you can also use
res/layout-land/sample_layout.xml for landscape orientation for all screen sizes or you can target landscape layouts for specific screen sizes as res/layout-medium-land/sample_layout.xml
note that all the layouts have the same name.
once you have your layouts ready, you need to take care of image resolutions also
once again in your res/ folder add images like this:
res/drawable-ldpi/sample_image.png // low density
res/drawable-mdpi/sample_image.png // medium density
res/drawable-hdpi/sample_image.png // high density
res/drawable-xhdpi/sample_image.png // extra high density
once again, all the images have the same name.
general guidelines for designing images are:
ldpi is 0.75x dimensions of mdpi
hdpi is 1.5x dimensions of mdpi
xhdpi is 2x dimensinons of mdpi
generally, I design mdpi images for a 320x480 screen and then multiply the dimensions as per the above rules to get images for other resolutions.
Android will automatically select the best combination of layout and image depending on the device. For example, for a high resolution medium size device, layout-medium and high density image will be displayed to the user.
Make sure you create emulators for all these combinations and test your app thoroughly. here's the official docs for more info:
https://developer.android.com/guide/practices/screens_support.html

m/h/xh dpi are the most important. Combine that with the (most common) resolutions and you should be fine for your "90%" target.

Android support screen design

I know about supporting multiple screens in Android and I use it in my app. But supporting different screen sizes and DPI makes your application size large. We all know about the 50mb file size limit in Google Play right? So, is it possible to create a folder like the following?
\layout-small-160
\layout-normal-240
If that is not possible do any one here knows how to support multiple screen sizes and its DPI's without using too much image to make my application size smaller?

I only give my suggestion and you can try it.
By default, we have three drawable folder drawable-ldpi(120), drawable-mdpi(160), drawable-hdpi(240).
When the App need image, Android will find the image according to the screen destiny. Obviously, the image in drawable-ldpi folder is fit if the app running on phone which have a low destiny.
But if there is no image in drawable-ldpi folder. Android will find if there is image in drawable-hdpi. If it exists, android will scale the image(0.5) and show it.
So you don't need to prepare images for every destiny. You only need to prepare the image for hdpi scrren. And for some individual images which demand accurate size, you need to prepare for the three destiny.
You could download some famous APK and extract them.Then enter the res folder to check how the author did.
Sorry for my poor English.

From Supporting Multiple Screens article of Android documentation:
To optimize your application's UI for the different screen sizes and densities, you can provide alternative resources for any of the generalized sizes and densities. Typically, you should provide alternative layouts for some of the different screen sizes and alternative bitmap images for different screen densities. At runtime, the system uses the appropriate resources for your application, based on the generalized size or density of the current device screen.
Therefore, yes it is possible to create folders for different layouts as you mentioned in your question. The following is a good practice of having your resources folder organized for different screen sizes and different bitmap drawables:
res/layout/my_layout.xml // layout for normal screen size ("default")
res/layout-small/my_layout.xml // layout for small screen size
res/layout-large/my_layout.xml // layout for large screen size
res/layout-xlarge/my_layout.xml // layout for extra large screen size
res/layout-xlarge-land/my_layout.xml // layout for extra large in landscape orientation
res/drawable-mdpi/my_icon.png // bitmap for medium density
res/drawable-hdpi/my_icon.png // bitmap for high density
res/drawable-xhdpi/my_icon.png // bitmap for extra high density
Yet, you do not need to provide alternative resources for every combination of screen size and density. The system provides robust compatibility features that can handle most of the work of rendering your application on any device screen, if you develop your application following the instructions described here.

2 suggestions:
Resize the images to be exactly the size you need. Use proper compression (use a professional application to edit the images, like photoshop, that optimize the image and compress it well).
Put part of the images on an external server and download all on the first use. Downloading the images from the server has the advantage that you know the device size, so you can download only the relevant sizes.

Case close.. It is posible to create a folder that has two modifier..
like this
layout-normal-hdpi ---- this will only set the view from specific phone that has 240 dpi and normal screen
thanks for all who commented and give an idea here..

Android: How to access different layouts depending of screen density in XML

I am wondering how to get different XML layout files to be read depending of density of the screen.
Now when I enter a layout file and set to so that it has a couple of buttons and have them set to a specific position, the position changes when I change to another screen density in the emulator. This is what should be happening what i understand- but How do I get the program to use different layouts depending of densities?
I have been reading on android dev. page on how to develop for different screens, but I didn't get the examples which were there.
I have been using dp/dip on sizes so no need to suggest that =)

you can do it by creating a layout for each standart screen sizes,
you can find here how to do it.
res/layout/my_layout.xml // layout for normal screen size ("default")
res/layout-small/my_layout.xml // layout for small screen size
res/layout-large/my_layout.xml // layout for large screen size
res/layout-xlarge/my_layout.xml // layout for extra large screen size
res/layout-xlarge-land/my_layout.xml // layout for extra large in landscape orientation
res/drawable-mdpi/my_icon.png // bitmap for medium density
res/drawable-hdpi/my_icon.png // bitmap for high density
res/drawable-xhdpi/my_icon.png // bitmap for extra high density
it means you should create sub-directory named as ("layout", "layout-small","layout-large","layout-xlarge","layout-xlarge-land") in res folder.
than create a main xml for each one with the same name.

By placing the layout XML files in different folders you can get Android to load the correct one depending on the screen density. For example, if you layout is called "main.xml":
Placing the file in /res/layout-ldpi/main.xml will mean it is used only in low density (or above)
Placing the file in /res/layout-mdpi/main.xml will mean it is used only in medium density (or above)
Placing the file in /res/layout-hdpi/main.xml will mean it is used only in high density (or above)
Placing the file in /res/layout-xhdpi/main.xml will mean it is used only in extra-high density
You can do the same sort of thing with all resources- drawables, strings, dimensions etc. (e.g. drawable-mdpi, or values-en [values only to be used in an English locale]). You can find the whole list of different device set-ups supported by this system at http://developer.android.com/guide/topics/resources/providing-resources.html (Table 2: Configuration Qualifier names)

Android, concerning the User Interface design

the more I read the Supporting Multiple Screens guide, the more I get confused.
if the layout folder's qualifier is based on size (small, normal, large and xlarge) and the drawable folder's qualifier is based on density (ldpi, mdpi,hdpi and xhdpi),
then how can I specify the size of the drawables/images??
should all the images inside the drawable folders have the same size (based on the normal screen size) but different densities (i.e. pic.png inside drawable.ldpi has the same width and height of pic.png inside drawable.mdpi but has different density)??
the problem is that each screen size may include the three densities (i.e. a large screen may be ldpi,mdpi or hdpi).
.how can I be designing the images on size basis and on density basis on the same time??
thank you.

36x36 for low-density
48x48 for medium-density
72x72 for high-density
96x96 for extra high-density
http://developer.android.com/guide/practices/ui_guidelines/icon_design.html
hope this helps.

In general you'll want the smallest pictures in ldpi, middle ones in mdpi, and larger in hdpi etc...
Even though it is technically possible for a device to have a "large" screen and an "ldpi" density manufactures have tended to stick to making devices with big screens be higher density as well.
EDIT:
The images only need to be designed with density in mind. Because if you take the same 100x100 pixel image and show it at 3 different densities it will appear largest (to human eyes) on the smallest density. So to account for that you make 3 images, lets say one 80x80, one 100x100, and one 120x120. Now if you show those 3 images across 3 densities the size that object appears to be to your eyes will be much closer than before.
the large, medium, small etc... qualifiers that you can add to the layout folders are not so much about any image resources themselves, but rather structuring the View components on the given page so as to make best use of the space available.
For instance, if your application has a list of items to choose from in it. On a tablet (large or xlarge) screen it may look nicer and be more effecient to have two or more columns of items displayed in your list on the screen. Whereas on a handset there may not be enough width (in portrait mode) to fit more than 1 column in. So to handle this situation you'd put a layout xml file inside the layout-normal folder that has a single column ListView. Then put another layout xml file in the layout-large folder that uses a GridView so that it can have an additional column
This image will show you roughly which folder the system will pull your images and/ or layout xml files from given the screen size and density.:
All of your image resources go in the drawable folders which are qualified with the densities. (ldpi, mdpi, hdpi etc)
The layout folders are what get qualified with the screen size (small, normal, large etc) The layout folders will contain xml layout files only, no images.