AndroidAppDevelopment FundamentalsforBeginners
Androidisanoperatingsystemdesignedprimarilyformobiledevices. Googlecreatedit,whichisbasedontheLinuxkernelandotheropensourceapplications.It'scommonintouchscreenmobiledeviceslike smartphonesandtablets.However,theyarenowemployedinAndroid Autoautomobiles,TVs,watches,cameras,andotherdevices.
AndroidOSwascreatedbyAndroidInc.,whichwasacquiredbyGooglein 2005.ForthesedevicestoworkonAndroid,varioussoftware(apps)such asgames,musicplayers,cameras,andsoonaredeveloped.TheGoogle PlayStorehasover3.3millionapplications.Theappiscreatedusingthe AndroidStudioprogram.Theseexecutableprogramsareinstalledthrough anAPKbundleorpackage(AndroidPackageKit).
Inthisandroiddeveloperguidepost,wewillstudythefoundationsof androidappdevelopmentfundamentals.We'lllookintoAndroid components,essentialconcepts,andmuchmore.However,beforewego intothedetailsoftheintricatefoldersandtheirsignificance,let'sgoover whatAndroidis.
WhatisAndroid?
Androidisamobileoperatingsystemcreatedbyagroupofdevelopers (mostlyGoogleandtheOpenHandsetAlliance).Theoperatingsystemis writteninJava(UI),C(Core),C++,andotherprogramminglanguages.
AndroidOSisaUnix-likeoperatingsystembasedonamodifiedLinux kernel.Itisintendedparticularlyformobiledevicessuchastouchscreens, smartphones,andtablets.ThefirstcommercialAndroidsmartphonewas introducedinSeptember2008,afteritwasrevealedinNovember2007.
Since2011,Androidhasbeenthebest-sellingsmartphoneoperating systemglobally,andontabletssince2013.Theoperatingsystemcurrently hasover5billionmonthlyactiveusers.
AndroidProgrammingLanguages
We'llstartwiththeAndroidprogramminglanguagebecausenothingis possiblewithoutit.Androidappsmaybewritteninoneofthreedifferent languages.Java,C++,andXMLarethethree.Thebackendoftheprogram isdevelopedinJava/C++,whilethefrontendiswritteninXMLmarkup language.InadditiontoJavaandC++,anewlanguageknownasKotlinhas recentlygainedpopularity.
Javaisanobject-oriented,class-basedprogramminglanguage.Oneofthe reasonsitisfavoredforAndroidappdevelopmentservicesisbecauseitis builttorunwithfewdependencies.Javaisageneral-purposeprogramming languagethatallowsdevelopertocodeonceandexecuteanywhere.This impliesthatJavacodethathasbeencompiledcanbeexecutedonany platformthatsupportsJava.
1.Java
C++isanotherprogramminglanguagethatmightbeusedtocreate applications.C++isageneral-purposeprogramminglanguageaswell.C++ wasinitiallyintroducedin1985.Thelanguagehasundergoneseveral revisionsovertheyears,andcurrentC++isobject-oriented,generic,and functional.
XMLisanextensiblemarkuplanguagethatsetsstandardsforencoding textsinahuman-andmachine-readablemanner.XML'sdesigngoals includesimplicity,universality,andonlineusability.
4.KOTLIN
Kotlinisacross-platform,general-purposeprogramminglanguagethatis completelycompatiblewithJava.Kotlininitiallysurfacedin2011,and GooglestatedinMay2019thatitisnowtheirpreferredprogramming languageforAndroidappdevelopers.Thelanguageissupportedby platformssuchas:
Android,
iOS,macOS,watchOS,tvOS
Windows,
Linux
Javascript
WebAssembly
LLVM
AndroidAppDevelopmentFundamentals
Androidappdevelopmentservicesbecomessimplewhenhireandroidapp developersorappdevelopmententhusiastsunderstandthecoreideas underlyingappdevelopmentbyandroiddeveloperguide.
We'llgothroughthefoundationsofAndroidappdevelopmentservices. Wewillgothroughtheappdevelopmentcomponents,thelanguageskills
2.C++
3.XML
necessary,theoptimumapplayout,andthewholelifespanoftheAndroid application.
AndroidComponents
ConsiderAndroidappcomponentstobebuildingblocksfordeveloping Androidapps.Eachcomponenthasadistinctrole,andeachcomponent hasitsownlifecycle.Someofthecomponentsareself-contained,while theothersareinterconnected.Therearefourimportantcomponentsthat weshallexamineindepth.
Activities
Activitiesaretheactionstakenbytheappwhenauserinteractswithit.It isconcernedwithuserinterfaceandscreeninteractions.Theoverall numberofactionsisdeterminedbytheapp'sfunctionality.Whentheapp islaunched,thefirstactivityisdone.Asaresult,everyappconductsat leastoneaction,whichisreferredtoasthe"MainActivity."
Theactivityiscarriedoutinthefollowingways:
Syntax:
publicclassMainActivityextendsActivity{
Theapp'sbackgroundactionsarereferredtoasservices.Itmaybe listeningtomusicwhileusingGoogleMapstogotoyourlocation.The majoraimofthiscomponentistoensurethattheprogramruns continuously.Tocompletetheresponsibilities,theservicemayrequirethe assistanceofanothersub-service.
publicclassMyServicesextendsServices{
//codefortheservices
//processes } Services
Broadcastreceivers
Whenrespondingtomessagesfromotherapplicationsorsystems,a broadcastisutilized.Broadcastreceiversreceivethebroadcastand respondappropriately.Whenaphone'sbatterybecomeslow,the SystemOSsendsabroadcastmessagetostartthebatterysaver,andthe appperformstheappropriateactivities.
Eachitemisrepresentedbyanintentobject,andthebroadcastreceiveris asubclassofBroadcastReceiver.Thebroadcastisreceivedbythecontext, andthepurposeistheconsequencedependingonthecontext.
publicclassMyReceiverextendsBroadcastReceiver{ publicvoidonReceive(context,intent){
Contentproviders
Whenoneapplicationrequestsdatafromanother,contentprovidersare utilizedtosendit.TheFacebookapp,forexample,demandsaccesstoyour contactsandmessages.TheContentResolverclasshandlesandmanages them.
ThisclassmakesuseofacollectionofAPIs(applicationprogramming interfaces)thatallowotherappstocarryouttransactions.
publicclassMyContentProviderextendsContentProvider{ publicvoidonCreate()
}
}
{} } Conclusion
StartwithShivTechnolabshirededicatedandroidappdevelopersifyou're newtoAndroidappdevelopmentservices.Asaresult,understandingthe foundationsofAndroidisimportant.Todevelopapplications,youmay utilizeeitherKotlinorJava,orbothatthesametime.Youmustbefamiliar withtheandroidappdevelopmentfundamentalsandsyntaxofoneorboth oftheseprogramminglanguages,aswellasthecollectionsystem, concurrencyandmultithreading,generics,andfunctionalprogramming.
