Fragment allows dividing the user interface of an Android application into independent and reusable modules. It provides ways to reuse components within and across activities and helps manage the activity lifecycle. Popular libraries like the Android Support Library allow using fragments in older Android versions back to 1.6. While fragments are useful for modularization, some argue they can overcomplicate the activity lifecycle and advocate for alternative approaches like custom views or architectures like Square's Flow library that simplify state management between fragments and activities.

1. [Android]
Fragment䛸䛾௜䛝ྜ䛔᪉䜢
⪃䛘䜛
@ichigotake - Studyplus Inc.
#potatotips ➨11ᅇ

2. 䜰䝆䜵䞁䝎
1. Fragment䛾䛚䛥䜙䛔
2. Fragment䛾䛴䜙䛔䛸䛣䜝
3. Fragment䜢ぢ┤䛩䛝䛳䛛䛡
4. ⮬ศ䛺䜚䛾ⴠ䛸䛧䛹䛣䜝

3. 1. Fragment䛾䛚䛥䜙䛔

4. Fragment䛸䛿
● Activity䝷䜲䝣䝃䜲䜽䝹䜢ᣢ䛳䛯䚸෌฼⏝䛧䜔䛩
䛔䝁䞁䝫䞊䝛䞁䝖
● 䛂䝍䝤䝺䝑䝖ᑐᛂ䜒⡆༢䛻ฟ᮶䜛䜘䟿䛃
● Android 3.0䛛䜙฼⏝ྍ⬟
○ support-v4䝟䝑䜿䞊䝆䜢฼⏝䛩䜜䜀 1.6 䛛䜙฼⏝ྍ

5. 䛧䛛䛧…

6. 2. Fragment䛾䛴䜙䛔䛸䛣䜝
● Ⰻ䛟䜒ᝏ䛟䜒䛂ᑠ䛥䛺Activity䛃
● 䝷䜲䝣䝃䜲䜽䝹䜒ព㆑䛩䜛஦䜒ከ䛔
● FragmentManager䛻㛵䛩䜛䝕䝞䝑䜾䛜䛧䛵䜙
䛔
● ඲ㇺ䜢ᤸᥱ䛧䛵䜙䛔≀䜢౑䛳䛶䛔䜛୙Ᏻ
● IlleagalStateException
● IlleagalStateException
● IlleagalStateException

7. 3. ௜䛝ྜ䛔᪉䜢ぢ┤䛩䛝䛳䛛䛡

8. ௜䛝ྜ䛔᪉䜢ぢ┤䛩䛝䛳䛛䛡
● Android - Fragments vs. CustomViews 䛻୍䛴䛾⤖ㄽ䜢
ฟ䛧䛶䜏䛯 - Qiita
○ http://qiita.com/KeithYokoma/items/9e049f12ca38d942e4fd
● 䛆⩻ヂ䛇Android Fragment䜈䛾཯ᑐኌ᫂
○ http://ninjinkun.hatenablog.com/entry/2014/10/16/234611
● Fragment䛻㛵䛩䜛↓ᩘ䛾䜽䝷䝑䝅䝳䝺䝫䞊䝖䛾Ꮡᅾ

9. ཧ⪃: Fragment vs. CustomViews 䛻୍䛴䛾⤖ㄽ䜢ฟ䛧䛶䜏
䛯
http://qiita.com/KeithYokoma/items/9e049f12ca38d942e4fd

10. ཧ⪃: Fragment vs. CustomViews 䛻୍䛴䛾⤖ㄽ䜢ฟ䛧䛶䜏
䛯
● Fragment䛿䝷䜲䝣䝃䜲䜽䝹䜒ᐇ⿦䜒」㞧
● Fragment䛿䝝䝬䜚䛹䛣䜝䜒ከ䛔
● CustomView䛷㈥䛘䜛⠊ᅖ䜒䛒䜛
● 䛭䜜䛷䜒Fragment䛜᭷⏝䛺ᡤ䜒䛒䜛
○ Activity䝷䜲䝣䝃䜲䜽䝹䜢㒊ရ໬
● 䝁䞁䝖䝻䞊䝷䛻䝻䝆䝑䜽䜢᭩䛛䛺䛔

11. ཧ⪃: Advocating Against Android Fragments
● http://corner.squareup.com/2014/10/advocating-against-android-fragments.
html
● 䛆⩻ヂ䛇Android Fragment䜈䛾཯ᑐኌ᫂ - ninjinkun's diary

12. Square Inc. 䛾ᡓ␎
● 䛂䝞䝑䜽䝇䝍䝑䜽䜢⟶⌮䛩䜛䛾䛻㠀ྠᮇ䛺䝖䝷䞁
䝄䜽䝅䝵䞁䛿ᚲせ䛺䛔䚹䛃
● Fragment䛾௦䜟䜚䛻䜹䝇䝍䝮䝡䝳䞊䜢౑䛖
● 䛭䛾䛯䜑䛻 square/flow 䜢స䛳䛯
https://github.com/square/flow

13. square/flow 䛸䛿
● 䝺䜲䜰䜴䝖䛾䝞䝑䜽䝇䝍䝑䜽⟶⌮䛾I/F䜢ᥦ౪䛩䜛
䝅䞁䝥䝹䛺䝷䜲䝤䝷䝸
● FragmentTransaction䛾⨨䛝᥮䛘
● Square Inc.〇

14. square/flow 䛾⫢
● 䝃䞁䝥䝹䛸௳䛾グ஦䛷ୡ⏺ほ䜢ᥗ䜐
● ⏬㠃㑄⛣䛻Fragment䛿୙せ
● ViewGroup#{removeAll,addView} +
Animation䜢⮬ศ䛷ᐇ⿦䛩䜛
● ⏝ព䛩䜛䛾䛿ᡭ㛫䛰䛜඲ㇺ䜢ᢕᥱ䛧䜔䛩䛔
● 䝃䞁䝥䝹䛾䜲䞁䝍䞊䝣䜵䞊䝇䛜䛝䜜䛔

15. square/flow ヨ⏝
● 䝃䞁䝥䝹䜰䝥䝸䛾ᐇ⿦䜢┿ఝ䜛
● ྍ⬟䛺㝈䜚Fragment䜢ᤞ䛶ཤ䛳䛶䜏䜛
● FragmentTransaction䛾௦⏝䛻square/flow
● ᶵ⬟ᐇ⿦䜢䜹䝇䝍䝮䝡䝳䞊䛷䝷䝑䝥䛩䜛
○ 䛂ᶵ⬟ᐇ⿦䛃䛿๓㏙䛾square䛾グ஦䛻䛚䛡䜛䛂Presenter䛃䛻䛒䛯䜛
● Activity䝷䜲䝣䝃䜲䜽䝹䛿Fragment䜈㞟⣙
● Activity䛿Fragment/View䛾attach/detachᢸᙜ
● Activity䛿䜲䝧䞁䝖䛻ᛂ䛨䛶ActionBar/Toolbar䜢ไᚚ

16. square/flow䛜䜔䛳䛶䛟䜜䛺䛔஦
● ⏬㠃㑄⛣䛭䛾䜒䛾
● Fragment┦ᙜ䛾View䛾䝷䝑䝟䞊
⮬๓䛷⏝ព䛩䜛䜒䛾䛜䛭䜜䛺䜚䛻䛒䜛
ᑟධ䝁䝇䝖䛿㧗䛔䛛䜒
ᑠ䛥䛔䜰䝥䝸䛺䜙…䠛

17. 4. ⮬ศ䛺䜚䛾ⴠ䛸䛧䛹䛣䜝
䜎䛰ᵓ᝿ẁ㝵䛷䛩䜘

18. 䜹䝇䝍䝮䝡䝳䞊ᐤ䛫
● Activity/Fragment䝷䜲䝣䝃䜲䜽䝹䜢฼⏝䛧䛺䛔
஦䛜⮬᫂ⓗ䛻䛺䜛
○ ౛) ListFragment䛾௦䜟䜚䛻ListView䜢⥅ᢎ䛩䜛
● Fragment(Manager|Transaction)䜢฼⏝䛧䛺䛔
Ᏻᚰឤ
● View#saveInstanceState䛜䛒䜛䛰䛡䛷䜒෌฼
⏝䛧䜔䛩䛔㒊ရ䛻ฟ᮶䛭䛖

19. 䜹䝇䝍䝮䝡䝳䞊ᐤ䛫䚷ᠱᛕ
● Activity/Fragment/View䛾㈐ົ䜢ᨵ䜑䛶⪃䛘䛶
タィ䛧䛺䛔䛸ΰ஘䛧䛭䛖
● View#onSaveInstanceState䛿ᑡ䚻ᢅ䛔㎞䛔
○ getSuperState() ᛀ䜜䛸䛛…
○ ័䜜䜜䜀ከᑡ䛿ゎᾘ䛥䜜䛭䛖䛷䛿䛒䜛䛜…
● ᐇ⿦䛩䜛䜉䛝View䛾䝁䞁䝇䝖䝷䜽䝍䛾⌮ゎ
○ ព㆑䛩䜛䝁䝇䝖/Ꮫ⩦䝁䝇䝖๐ῶ䛾䛯䜑䛻䛂඲㒊䛾䝁䞁䝇䝖
䝷䜽䝍䜢ᐇ⿦䛩䜛䛃䝹䞊䝹䛻䛩䜛䛾䜒ᡭ䛛?

20. Fragment䛜᭷⏝䛺䛸䛣䜝
● View䛻䛿䛺䛔䝷䜲䝣䝃䜲䜽䝹䜢㒊ရ໬
○ Activity#{onResume,onPause,onOptionMenu*}䛸䛛
● Fragment䜢๓ᥦ䛸䛧䛯䝷䜲䝤䝷䝸䛾฼⏝

21. ព㆑䛩䜛஦䜢ῶ䜙䛩䛯䜑䛻䛺䜛䜉䛟㑊䛡䛯䛔஦
● Fragment#{startActivityForFragment,onActivityResult}
○ Y.A.M 䛾 㞧グᖒ: Android Support Package 䛾 Fragment 䛛䜙 startActivityForResult() 䜢౑
䛖䛸䛝䛾ὀពⅬ
○ 䝛䝇䝖䛥䜜䛯 Fragment 䛷䛿 #onActivityResult 䛜࿧䜀䜜䛺䛔 · Issue #2 · kuroyam/tips
● FragmentManager䜢䝯䞁䝞ኚᩘ䛸䛧䛶ᣢ䛴
○ 䛂䛭䛾䜲䞁䝇䝍䞁䝇౑䛘䛺䛔䜘䛃౛እ䛜ฟ䜛䝸䝇䜽
● FragmentTransaction
○ 㠀ྠᮇ/ྠᮇ 䛾䛹䛱䜙䛻䛧䛶䜒ព㆑䛧䛺䛔䛸䛔䛡䛺䛔஦
䛜䛒䜛…
● Fragment䛾ධ䜜Ꮚ
○ ౛) PagerAdapter䛷ViewGroup䜢┤᥋ᢅ䛳䛶䜏䜛

22. ⚾ぢ䜎䛸䜑
● ྛ✀䝁䞁䝫䞊䝛䞁䝖䛾㈐ົ䜢⪃䛘┤䛩
○ Activity: ୺䛻Intent,ActionBar/Toolbar䜢ᢅ䛖
○ Fragment: ୺䛻Activity䝷䜲䝣䝃䜲䜽䝹䜢ᢅ䛖
○ CustomView: ༢୍䛾View䜢ᵓ⠏䛩䜛
● ᶵ⬟ᐇ⿦䛿䜹䝇䝍䝮䝡䝳䞊䜈ᢲ䛧㎸䜐
● 㑊䛡䜙䜜䜛᫬䛻䛿Fragment䜢㑊䛡䜛
○ ↓⌮䛻㑊䛡䜛䛸䛭䜜䛿䛭䜜䛷㎞䛔䛾䛷Ẽ䜢䛴䛡䜛
● せ௳䛻ᑐ䛧䛶ᚲせ᭱ప㝈䛾䝁䞁䝫䞊䝛䞁䝖䜢౑䛔䛯䛔

23. ⚾ぢ䜎䛸䜑 square/flow䜢౑䛖䛺䜙
● 䜎䛪䛿䝃䞁䝥䝹䜰䝥䝸䜢ㄞ䜒䛖
● Activityෆ䛾ᵓᡂ䛜䝅䞁䝥䝹䛺䜙༑ศ䛭䛖
○ ⬺Fragment!
○ Fragment䛿onOptionMenu࿘㎶䛰䛡䜢౑䛖䚸䛸䛔䛖䛾䜒
ᡭ䛛
● Ꮫ⩦䝁䝇䝖䜒䛭䜜䛺䜚䛻䛒䜛
● 䜰䝥䝸䛾タィ䚸✵Ẽឤ䛻㛵䜟䜛䛾䛷ៅ㔜䛻

24. 䝥䝻䝎䜽䝅䝵䞁䛷䛹䛖䛩䜛䛛…
● Fragment䜢ᤞ䛶䜛䛾䛿䝝䜲䝁䝇䝖
● Fragment䜢ᤞ䛶䛪䛸䜒ฟ᮶䜛஦䛿䛒䜛䛿䛪
○ 㒊ศⓗ䛻᪂䛧䛔ᐇ⿦䝟䝍䞊䞁䜢౑䛖䛸䛛
● 」㞧䛺஦䜢⌮ゎ䛧䛶౑䛖䛾䜒⌧ᐇゎ䛸䛧䛶…

25. 䛥䛔䛤䛻
● ⚾ぢ䛿䜎䛰ᵓ᝿ẁ㝵䛷䛩䜘
● ᐇ⿦䜢ぢ┤䛩㝿䛾ཧ⪃䛻䛺䜜䜀ᖾ䛔

26. ཧ⪃䝸䞁䜽
● Activity/Fragment/View
○ Android - ௒䛥䜙⪺䛡䛺䛔 Activity 䛸 Fragment 䛾౑䛔ศ䛡 - Qiita
○ Android䛷⊂⮬View䜢స䜛䛸䛝䛾4䛴䛾Tips - Qiita
○ Android - Fragment 䛿ᮏᙜ䛻ከᵝ䛺䝕䝞䜲䝇䜈ᑐᛂ䛩䜛၏୍䛾᪉ἲ䛺䛾
䛛 - Qiita
● square/flow
○ 䛆⩻ヂ䛇Android Fragment䜈䛾཯ᑐኌ᫂ - ninjinkun's diary
○ square/flow
○ alexfu/flow-sample - 䝅䞁䝥䝹䛺䝃䞁䝥䝹ᐇ⿦
● View䛾ሙྜ䛿 getSuperState() 䜢ᛀ䜜䛪䛻…
○ fragment䛾≧ែಖᣢ䛻䛴䛔䛶 - 䛖䛥䛜䛻䛳䛝

27. ཧ⪃䝸䞁䜽
● ActionBarSherlock/actionbarcherlock-samples
○ ౛) ActionBarSherlock/ContextMenus.java at master ·
JakeWharton/ActionBarSherlock
● ᐇ⿦䝟䝍䞊䞁䛾ぢ┤䛧䛸䛧䛶EventBus䜢᳨ウ䛩䜛䛸䛛
○ Android 䛷 EventBus 䜢౑䛖䛸䛝䛾䜸䝺䜸䝺䝥䝷䜽䝔䜱䝇 - Qiita
○ Android - EventBus 䛿䛹䛣䛷䛴䛛䛖䜉䛝䛛 - Qiita

28. 䛚䛧䜎䛔