Peb npaj koj qhov kev pom! Kev ua tau zoo nrog ONMA scout android app kev txhim kho yog lav.
Hu rau
Yog tias koj xav paub yuav ua li cas los tsim ib qho Android app, nyeem rau. Koj yuav kawm cov hauv paus ntawm Kev Ntseeg, Activity Lifecycle Callbacks, Nyiam-Cov ntsiab lus, thiab Java Code. Ces, koj yuav kawm yuav ua li cas los tsim ib lub app customized uas ua tau raws li koj xav tau. Lub Android-Betriebssystem zoo li yuav nrov nrog koj cov neeg siv khoom thiab yuav nce koj cov nyiaj tau los. Qhov zoo tshaj plaws yog qhov yooj yim ua koj tus kheej.
Android app developers tuaj yeem ntim lawv cov kev xav kom ua rau lawv muaj rau cov neeg siv. Qhov no tso cai rau Android OS kom paub cov ntawv thov twg raug teeb tsa ntawm lub cuab yeej, thiab xa cov lus thov mus rau lub app uas tsim nyog tshaj plaws. Piv txwv li, ib lub hom phiaj tuaj yeem xa mus rau Google Maps thaum tus neeg siv tshawb nrhiav qhov chaw tshwj xeeb, los yog them nyiaj txuas rau SMS. Hauv ib puag ncig Android, cov hom phiaj yog siv los txav ntawm ib daim ntawv thov mus rau lwm qhov, thiab koj tuaj yeem siv lawv los taug qab hauv daim ntawv thov.
Lub hom phiaj yog lub hauv paus ntawm Android kev sib txuas lus sib txuas. Lub hom phiaj tuaj yeem siv rau kev hloov pauv mus rau lwm daim ntawv thov, qhib chaw, los yog xa SMS. Ib qho piv txwv ntawm kev xav yog ib txoj hauv kev hu ua setData. The setDataAndType() txoj kev tso cai rau koj qhia cov ntaub ntawv URI. Nws lub npe yog pom tseeb, tab sis nws tseem ceeb heev uas yuav tsum nco ntsoov tias nws tuaj yeem teeb tsa ob hom URI thiab MIME. Qhov no yog ib qho cuab yeej muaj txiaj ntsig zoo rau kev tsim Android app.
Lub hom phiaj yog cov cuab yeej zoo rau kev sib koom tes nrog lwm cov ntawv thov. Los ntawm kev siv cov kev pabcuam no, koj lub app tuaj yeem tsim cov haujlwm tshiab lossis tau txais cov uas twb muaj lawm los ua. Nws tseem tuaj yeem xa cov lus thiab cov lus qhia rau cov neeg txais xov xwm tshaj tawm. Yog tias koj lub app muaj API los nthuav tawm cov ntaub ntawv, koj tuaj yeem siv qhov no. Yog tias koj lub app tseem tsis tau muaj, koj tuaj yeem siv qhov sib sib zog nqus txuas thiab kev cai URL schemes los tso nws. Qhov no yuav tso cai rau koj kom tau txais koj lub app thiab ua haujlwm tsis muaj sijhawm.
Lub hom phiaj tuaj yeem yog qhov tseeb lossis tsis tseeb. Tus qub qhia txog cov haujlwm lossis cov khoom uas yuav tsum tau pib thiab xaus. Qhov sib txawv, tom kawg tshaj tawm ib qho kev nqis tes ua, thiab Android system phim qhov kev txiav txim mus rau qhov tseeb. Yog tias koj xav siv ib qho app los thaij duab, koj tuaj yeem teem lub hom phiaj ua li ntawd. Thiab, yog tias koj tab tom sim pib lub app tshiab, koj tuaj yeem tsim lub hom phiaj meej rau lub hom phiaj ntawm kev ntes cov duab.
Yog tias koj tab tom tsim Android app, koj yuav tsum paub siv Activity Lifecycle Callbacks. Cov no yog cov txheej txheem hu ua thaum pib ua haujlwm, nres, thiab rov pib dua. Cov txheej txheem no yog siv los txuag cov ntaub ntawv thov thiab ua cov ntaub ntawv tsis tau khaws cia thaum muaj kev ua ub no zais lossis rov pib dua. Lawv kuj tuaj yeem raug hu kom unbind los ntawm cov kev pabcuam xws li Bluetooth thiab Wi-Fi.
Thaum tsim ib qho Android app, koj yuav tsum kawm paub siv Activity Lifecycle Callbacks kom tsis txhob muaj teeb meem ntau yav tom ntej. Thaum koj tab tom tsim koj lub app, koj yuav tsum paub thaum twg cov xwm txheej no tshwm sim thiab koj tuaj yeem ua li cas rau lawv. Koj tuaj yeem siv lub onStart() txoj kev kom tau txais kev ceeb toom thaum muaj kev ua si pib khiav. OnStart() yog hu ua tom qab onCreate() txoj kev tau invoked. Txoj kev no yuav tso cai rau koj cov dej num nkag mus rau hauv lub xeev pib thiab npaj rau cov neeg siv kev sib cuam tshuam.
Lub onStart() txoj kev hu ua ua ntej kev ua ub ua no puas. Txoj kev no hu ua thaum pib ua haujlwm, tab sis nws kuj yuav raug hu thaum qhov kev ua ub no xaus. Yog tias qhov kev ua si tsis tiav, lub kaw lus yuav rho tawm nws ib ntus kom dawb qhov chaw. Qhov yogFinishing() txoj kev tuaj yeem pab koj sib txawv ntawm ob qhov xwm txheej no. OnStart() thiab onStop() cov txheej txheem yog cov feem ntau siv txoj kev los xyuas txog lub lifecycle ntawm ib qho kev ua si.
OnDestroy() yog qhov kawg ntawm lub neej hu rov qab rau ib qho haujlwm. Yog tias koj hu nws ua ntej qhov kev ua tiav, qhov system yuav tsim ib qho tshiab. Qhov kev hu rov qab no yuav tsum tso cov peev txheej uas tsis tau tso tawm los ntawm kev hu rov qab yav dhau los. Kev hu xov tooj rau lub neej tuaj yeem pab koj tswj koj daim ntawv thov kev ua haujlwm. Txawm li cas los, Nws yog qhov zoo tshaj plaws los siv cov kev hu no tsuas yog tias koj paub tseeb tias lawv yuav tsim nyog.
Thaum tsim ib qho Android app, Nws yog ib qho tsim nyog kom paub siv Preference-Elements. Yog koj tsis paub yuav ua li cas, koj tuaj yeem kawm paub ntau ntxiv txog nws los ntawm phau ntawv qhia no. Nws piav qhia txog kev siv Preference-Elements hauv txoj hauv kev yooj yim. Preference-Elements yog ib txoj hauv kev los npaj cov chaw rau hauv pab pawg. Lawv siv los tso saib cov chaw ntawm cov ntxaij vab tshaus sib txawv.
Txhawm rau teeb tsa qhov kev nyiam tshaj plaws, koj yuav tsum tsim subclass ntawm Preference.BaseSavedState thiab dhau nws tus nqi boolean, uas qhia seb tus nqi puas tau txais kev cawmdim ua ntej. Ces, koj tuaj yeem siv tus nqi txuas ntxiv thiab hloov kho UI. Xwb, koj tuaj yeem siv tus nqi pib. Thaum koj tau teeb tsa qhov nyiam, Koj tuaj yeem siv cov Preference-Elements.
Qhov kev nyiam yog qhov yooj yim tshaj plaws hauv tsev thaiv hauv Android app. Nws sawv cev rau ib qho chaw tshwj xeeb nrog tus khub tseem ceeb-tus nqi. Piv txwv li, ib daim ntawv teev cov checkboxes nyob rau hauv qhov chaw seem ntawm ib qho app muaj ib lub checkbox thiab ib EditTextPreference qhia ib daim ntawv teev cov checkboxes. Ib yam li ntawd, ib qho EditTextPreference tuaj yeem siv los khaws ib tus nqi ntawv.
Koj tuaj yeem siv qhov Preference-Elements API los tsim kom muaj tus neeg siv-phooj ywg interface rau koj lub Android app. Koj tuaj yeem siv Preference-Elements ntxiv cov chaw tshiab thiab tswj cov uas twb muaj lawm. Preference-Elements tso cai rau koj los tsim ib qho UI rau koj lub Android app uas zoo ib yam nrog cov nyiam hauv lwm cov apps hauv Android. Koj tuaj yeem tsim ib tus neeg siv interface siv ntau yam sib txawv subclasses ntawm Preference class thiab tshaj tawm lawv hauv koj cov ntaub ntawv XML.
Ntxiv cov node rau qhov nyiam hierarchy yog ib qho yooj yim thiab yooj yim. Preference-Elements yog API uas pab cov neeg tsim khoom tsim Android apps uas yooj yim los tswj. Nrog API no, koj tuaj yeem tsim ib qho Android app uas muaj cov yam ntxwv tag nrho. Qhov tseem ceeb yog kom paub tseeb tias koj nkag siab li cas Preference-Elements ua haujlwm thiab siv nws li cas hauv koj tus kheej app. Qhov no yuav pab koj kom tsis txhob muaj kev ntxhov siab yav tom ntej.
Yog tias koj yog tus tsim tawm Android, Tej zaum koj yuav paub txog qhov tseem ceeb ntawm kev siv Java Code rau koj daim ntawv thov mobile. Cov lus muaj ntau yam zoo heev thiab tuaj yeem siv los ntawm ntau lub platform sib txawv, suav nrog Android thiab iOS. Nws kuj yog cross-compilable thiab kawm tau yooj yim haum. Koj yuav tsum paub qhov no, vim Java yog ib hom lus nrov tshaj plaws rau Android app kev txhim kho. Cia wb mus saib seb yog vim li cas koj thiaj li yuav tsum siv Java Code rau koj lub Android app tsim.
Ua ntej, Koj yuav tsum kawm cov ntsiab lus ntawm Java. Koj tuaj yeem kawm paub tsim ib chav kawm singleton, cov chav kawm suav, thiab hom interface nrog Java los ntawm kev siv lub cuab yeej hu ua Android Studio. Nws yog ib lub tswv yim zoo kom paub tseeb tias lub npe ntawm chav kawm lossis hom yog ua raws li hom lus cov cai rau npe.. Txoj kev no, koj tuaj yeem tsim lub mobile app sai sai.
Thib ob, Nws yog ib qho tseem ceeb kom nkag siab txog architecture ntawm Android khoom siv. Nws yog ib qho tseem ceeb kom nkag siab tias Android yog lub lag luam tawg nrog ntau yam khoom siv sib txawv ua haujlwm sib txawv. Kev txhawb nqa ntau dua txhais tau tias kev saib xyuas ntau dua, kuaj, thiab cov nqi. Ntxiv rau, koj lub app yuav tsum tau txhawb nqa ntau qhov sib txawv sensors thiab UI chaw. Thiab, koj tsis xav tsim ib daim ntawv thov ntau lub platform yog tias koj tsis muaj kev paub txog kev siv txhua lub platform sib txawv.
Thaum Java paub txog nws cov lej cim, nws tsis txhawb coroutines. Yog tias koj siv Kotlin, koj tuaj yeem txuas ntxiv cov chav kawm uas twb muaj lawm thiab ntxiv cov npe ua ntej rau lawv lub npe. Thaum Java tsis txhawb nqa cov haujlwm txuas ntxiv, koj tuaj yeem tau txais cov haujlwm ntawm niam txiv hauv chav kawm. Kotlin yog cov lus tseem ceeb rau Android app txhim kho. Ntxiv rau Java, koj tseem yuav pom tias Kotlin txhawb ntau yam kev ua lej. Los ntawm kev kawm Kotlin, koj tuaj yeem tsim cov ntawv thov Android uas nrawm thiab tsis muaj kab mob.
Xamarin yog lub hauv paus kev txhim kho ntoo khaub lig rau kev tsim cov ntawv thov mobile. Lub moj khaum no tso cai rau koj siv ib hom lus programming thiab cov tsev qiv ntawv sib koom hauv txhua lub platform. Qhov no muaj txiaj ntsig yog tias koj xav tau hloov pauv koj lub app, lossis yog tias koj muaj qhov sib txawv ntawm tib lub app ntawm cov khoom siv sib txawv. Yog tias koj siv Xamarin ntawm iOS, koj tuaj yeem siv iOS SDK nrog rau Xamarin cov ntaub ntawv los tsim cov UI zoo ib yam thoob plaws lub platform.
Xamarin apps qhia 75% ntawm cov cai thiab muab tag nrho nkag mus rau lawv cov functionality. Lawv kuj siv platform tshwj xeeb kho vajtse acceleration thiab muaj cov neeg siv interfaces. Xamarin yog qhov kev xaiv zoo rau Android app kev txhim kho yog tias koj tab tom nrhiav kev daws teeb meem hla lub platform. Nws yooj yim kawm, thiab nws kuj tseem yooj yim rau cov neeg tsim khoom uas muaj kev paub dhau los nrog C #. Nws yog qhov kev xaiv zoo tshaj plaws rau cov pib tshiab tab tom nrhiav pib nrog kev txhim kho kev sib koom ua ke.
Xamarin apps yog nyob rau hauv cov khoom siv hauv Android. Raws li qhov tshwm sim, lawv muaj UI zoo thiab cov neeg siv kev paub. Txawm li cas los, lub downside ntawm lub platform no yog lawv cov hneev taw loj, uas tuaj yeem qeeb lub sijhawm rub tawm. Raws li qhov tshwm sim, cov neeg tsim khoom yuav tsum tau txo lawv cov app qhov loj kom nws lub teeb. Qhov no yuav tsis yog qhov kev xaiv zoo tshaj plaws rau cov neeg siv feem ntau. Kuj, lub zej zog Xamarin tseem tshiab thiab xav tau kom loj hlob. Nws tseem nyuaj me ntsis kom tau txais kev pab, yog li koj yuav tsum ua siab ntev nrog cov cuab yeej no.
Xamarin SDK tau tsim los rau cov neeg tsim khoom los ntawm Microsoft. Nws yog qhib qhov chaw nyob rau hauv MIT daim ntawv tso cai thiab muaj raws li ib feem ntawm Visual Studio. Qhov no txhais tau tias nws yog qhov kev xaiv zoo dua li lwm lub platform. Microsoft tau txais Xamarin hauv 2016 ua kom nws yooj yim dua rau kev siv thiab ua txoj hauv kev rau kev txhim kho txuas ntxiv. Raws li qhov tshwm sim, ntau tus tsim tawm tam sim no tig mus rau Xamarin rau Android app kev txhim kho.