Android Universal App Approach -

i want develop universal app . novice approach .that means single apk both tablet , phone application . had go through

support library

fragments

my aim build different ui tablet , phone inside single apk .

i had read getting app ready jelly bean , nexus 7 . article mention that

res/layout/activity_home.xml  take advantage of space on 7” screen might provide alternative layout:  res/layout-sw600dp/activity_home.xml  sw600dp qualifier declares these resources devices have screen @ least 600dp available on smallest side.       furthermore might provide different layout 10” tablets:  res/layout-sw720dp/activity_home.xml 

that means can use different layout different device . confuses me

edit 1 :: scenario

suppose

if phone ui layout contains one-view pager ,   tablet ui layout contain two-view pager  .  

how can achieve ?? in article says designe different layout same name different screen , keep corresponding folder . doubt arise exceptions if try initialize widget component of tablet layout when app running in phone .

edit 2 : idea came mind determine type of device using ie tab or phone .

determine if device smartphone or tablet?

then avoid initialization of widgets if app phone . there better way ??

edit 3 : application support 2.3 higher versions

if layouts tablet holds additional widgets compared phone layout .how initialize , use . hope understood need . please clarify doubt

when face problem, create following structure.

res/layout res/layout-sw600dp 

then distinguish values , other resources,

res/values res/values-sw600dp res/values-sw720dp 

you noticed there one layout directory , two values directory specify margins , paddings , other resources. single layout can used 7" 10" tablet. scenario, can define layout-sw720dp. did due reduce compilation time of layouts.

i have different layouts in phone , tablet. example, have listview in first screen, when user click on item, open other activity , there detailview that. in tablet, have left side listview , right side detailview.

so so, in values/strings, place following code,

<bool name="istablet">false</bool> 

and same tablet values-sw600dp/strings

<bool name="istablet">true</bool> 

now, come part of coding. have splash screen , has common layout. display common screen. when user click on button, check whether tablet or not. check it,

boolean istablet = getresources().getboolean(r.bool.istablet); 

you have flag indicate whether application running on phone or tablet.

i have created 2 packages,

com.phone com.tablet 

then per flag, direct activity phone package , tablet package.

example,

if(istablet)     startactivity(this,tabxyz.class); else     startactivity(this,phxyz.class); 

and approach has solved problem.