+ Git l phn mm qun l m ngun phn tn c pht trin bi Linus Torvalds
dnh cho vic pht trin Linux kernel. Git l phn mm m m c phn phi theo
giy php cng GPL2. Git c kh nng chy trn nhiu h iu hnh khc nhau nh
Linux, Windows, Mac OSX.+ Repository (nh kho) hay c gi tt l Repo n
gin l ni cha/c s d liu (database) tt c nhng thng tin cn thit duy tr
v qun l cc sa i v lch s ca d n. Trong Repo c 2 cu trc d liu chnh l
Object Store v Index. Tt c d liu ca Repo u c cha trong th mc bn ang
lm vic di dng folder n c tn l .git (khng c phn tn trc du chm).
+ Object storeObject store l tri tim ca Git, n cha d liu nguyn
gc (original data files), cc file log ghi chp qu trnh sa i, tn ngi
to file, ngy thng v cc thng tin khc.
Git c 4 loi object l:Blobs, Trees, Commits, Tags
- Blobs: l file nh phn c th cha c mi loi d liu bt k l d liu ca
chng trnh g.
- Trees: lp i din cho thng tin th mc nh thng tin nh danh ca
blob, ng dn, cha mt t metadata cha thng tin cu trc v cc th mc nh c
trong th mc .
- Commits: Cha metadata c thng tin v mi th nh tn tc gi, ngi ti
ln (commiter), ngy ti ln, thng tin log...
- Tags: nh du cho d c. thy v 1 ci tn di nh l
9da581d910c9c4ac93557ca4859e767f5caf5169, chng ta c th tn tag l
Ver-1.0- Alpha. D nh v d s dng hn.
+ Index: l file nh phn ng v tm thi miu t cu trc th mc ca ton b
Repo v trng thi ca d n c th hin thng qua commit v tree ti mt thi im
no trong lch s pht trin. Git l mt h thng truy tm ni dung (content
tracking system). Index khng ha ni dung file m ch dng truy tm
(track) nhng th m bn mun commit.
+ ADB l g? ADB, l cch gi ngn gn ca Android debug bridge, bn c th
hiu y l mt cng c gip bn s dng cc dng lnh giao tip vi in thoi
Android ca bn. Mt khi bn ci t ADB, v Android c kt ni vi my tnh thng
qua USB, bn c th g lnh s dng Android ngay trn my tnh.Vi ngi dng bnh
thng, ADB thng dng flash hay root Android, thm ch cn c dng chuyn d
liu t my tnh vo Android vi quyn root.+ AOSP l g? AOSP, l vit tt ca
cm t The Android Open Source Project, dch ra Ting Vit th n l D n M
Ngun M Android hay y l phin bn Android nguyn bn nht c to ra bi
Google. y cng chnh l cha ca rt nhiu ROM ch khc c cc hng sn xut in
thoi, hoc ngi dng ti v v chnh sa theo h, nh Samsung th lm ra
TouchWiz, HTC th lm ra Sense cn Oppo th lm ra ColorOS.
Mt ROM Android gc ca d n AOSP ch vo khong 200 300 MB, nhng sau
khi qua tay cc nh sn xut ROM th n s nng ti khong vi GB :D. C ngha l
nu bn s dng c bn ROM Android gc th my s chy rt nhanh, mt m nhng c
th mt i nhiu th hay ho c nh sn xut nh km theo.
+ Bootloader l g? Hiu mt cch n gin, Bootloader c tc dng tng t nh
vi BIOS/UEFI trn my tnh ca chng ta. Khi bn nhn nt khi ng Android,
iu u tin n lm chnh l chy Bootloader. Sau khi Bootloader c khi ng
xong, n s load tip Recovery hoc Kernel my, v cui cng mi l load ROM
(H iu hnh).Mi my Android khi sn xut u b nim phong bng cch kha
bootloader, tc bn khng th nghch ph g y nu khng s dng cc phn mm
chuyn dng t nh sn xut, chng c tc dng kim tra nim phong my ca bn.+
Dalvik l g? Khi bn flash ROM cho Android, bn phi thc hin vic xa
Dalvik Cache. c th hiu c ngha ca iu ny, bn cn phi bit Dalvik l
g.
Dalvik l trnh bin dch Java trn Android, hiu theo cch n gin n l
chnh l th c bn nht gip phn mm c th chy trn Android. V d, APK chnh l
nhng phn mm Java c vit ring cho Android, m Android mun chy Java th
cn phi c Dalvik c chng. Dalvik l mt trnh bin dch Java cc k thn thin
vi Android, c Google s dng trn cc h iu hnh Android mi nht ca h, trc
y th Google s dng mt trnh bin dch khc, gi l ART.
Dalvik Cache l b nh ca Dalvik, n duy tr nhng dng code Java khi
Android x l. Nu bn khng xa Dalvik Cache, th Dalvik s gp rc ri trong
vic x l code Java trn ROM mi.
+ Deodex l g? Deodexed ROM l tp hp ca tt c file APK v OS c bin
dch v sp xp di 1 file duy nht, gi l classes.dex. V tt c code u nm
trong 1 file duy nht nn s d dng hn trong vic ty chnh ROM. Thnh ra
Deodex rt c a chung bi cc bn mod ROM, cc lp trnh vin chuyn to
ROM.
Tuy vy, cc code ny u cn thm thi gian bin dch li trn Dalvik.
+ GAPPS l g? Khi flash ROM, bn s thng bt gp cm t GAPPS, v h thng
yu cu bn flash file GAPPS trc khi flash ROM. V sao vy?GAPPS l file
cha ton b nhng ng dng ca Google trn Android, nu in thoi bn khi ng m
khng c nhng ng dng ny th bn s khng th dng GPS, khng th ng b d liu,
khng th dng ti khon Google ni chung l tt c nhng th c lin quan ti
Google .
Mi phin bn Android li s dng mt file GAPPS ring, thng bn s c cung
cp link download GAPPS khi lm theo cc hng dn flash ROM, nhng nu h
khng cp n n th bn vn c th dng ng dng Gapps Manager ti file GAPPS
thch hp vi my bn.
+ Kernel l g? Ni v Kernel, th Kernel khng phi l th m ch mi in
thoi Android mi c. V c bn, y l lp nm gia my v h iu hnh. Mi h iu hnh
nh Windows, Mac, iOS u c Kernel ca ring mnh.
in thoi Android s dng Linux Kernel, hay cn gi l Nhn Linux. Mi
khi phn mm mun giao tip vi phn cng, n u phi thng qua Kernel, k c
nhng thay i nh nh tng volume hay cao hn l gi in, tt c chng u phi
thng qua Kernel.
Mi ROM khc nhau li s dng Kernel khc nhau, ty theo cu trc ca h iu
hnh.
+ Odex l g? V mt k thut, thut ng ny kh kh c th gii thch v c th
hiu, nhng y l Toonima, v y l bi dnh cho ngi mi nn mnh c th m t Odex
theo cch khc bn d hnh dung hn.
Tm gn v Odex ch trong mt cu: Odex l trnh bin son trc ca file
.dex. Tc file ny c ti u ha chy trn Dalvik.
Odex ROM chnh l ROM c ti u ha, do n mt t thi gian hn khi ng v
ngc li file ROM cng s kh chnh sa hn sau khi c ti u ha.+ Custom
Kernel?
Bn phi root mi s dng c custom kernel. Xem v root ti y. Nh backup
mi th trc khi lm mi th.
Custom kernel cho php bn iu khin c xung nhp CPU, GPU do cho php
bn qun l xung nhp tt hn (gim xung khi sleep my, tng xung khi bt my)
do thi lng pin s tt hn.
Lm tng m lng loa, cho php m kha m khng chm n phm cng....
i km vi nhiu phn mm m developer cung cp, cho php can thip vo my
su hn. Nng cao im benchmark ca thit b.
Custom kernel ph bin: Franco kernel, infamous kernel...Bn mun tm
kernel cho my ca bn. Bn vo trang forum.xda-developers.com sau g tn
thit b ca bn vo, vo phn kernel tm hoc phn Android Original
Development.
Vy l cc bn hiu thm v kernel hy n xem cc bi vit sau nh.
