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Book Reader Implementation Notes with Android V...
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FUJI Goro
April 16, 2016
Technology
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Book Reader Implementation Notes with Android ViewPager 2016
https://github.com/gfx/TinyPdfReader
の解説です。
FUJI Goro
April 16, 2016
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Transcript
ಡॻը໘࣮ͷࣄ݅ ~ Android ViewPagerฤ ~ 2016/4/15 ిࢠॻ੶ษڧձ FUJI Goro (gfx)
ࣗݾհ
ࢀর࣮ • ͜ͷࢿྉͷࢀর࣮ҎԼʹ͋Γ·͢ • https://github.com/gfx/TinyPdfReader • ίΞϩδοΫ200ߦ͘Β͍ • DeploygateͰAPKΛ৴͍ͯ͠·͢ •
https://dply.me/xntdx6
ViewPagerجૅࣝ • AOSPͷҰ෦ (support library) • εϫΠϓͰࠨӈʹҠಈ͢ΔViewGroup • λϒҰൠɺಡॻը໘ͳͲʹ͏ •
ϖʔδͷਐΉํLTR(left-to-right)
ϑΝΠϧ#1 ϖʔδૹΓ͕ͬ͞Γ͢Δ
ϖʔδૹΓ͕͍ • ʮBookʯʢࠓճPDFʣ͔Β1ϖʔδऔΓग़ ͯ͠bitmapΛੜ͢Δͷʹ100 ~ 300sec͔͔ Δ • ͯ͢UIεϨουͰॲཧ͢ΔͱɺϖʔδૹΓ Ͱʮࢦ͕Ҿ͔͔ͬΔʯײ͕͢͡Δ
ViewPagerͷ࣮ • ViewPagerɺʮݱࡏͷϖʔδʯͱʮલޙͷ ϖʔδʯͷ3ϖʔδͷviewΛߏங͢Δ • ʮ࣍ͷϖʔδʯʹҠಈ͢Δલʹͦͷ࣍ͷϖʔ δͷviewΛߏங͢ΔͷͰɺͦ͜ͰඦϛϦ͔ ͔ΔͱʮϖʔδૹΓ͕٧·ΔʯΑ͏ʹײ͡Δ
#1 ͷղܾ • ViewPagerʹҰ୴ۭͷviewΛ͠ɺbitmapੜ όοΫάϥϯυεϨουͰߦ͏ • bitmap͕ੜͰ͖ͨΒviewʹͯ͠ඳը͢ Δɺ͜ͷͱ͖alphaʢಁ໌ʣͰΞχϝʔ γϣϯͯ͠ʮ;Θͬͱʯදࣔ͞ΕΔΑ͏ʹ͢ Δͱࢹ֮తʹ༏ͯ͘͠Α͍
PdfPagerAdapter: 1ทͷॲཧ ϓϨʔεϗϧμ7JFXΛͭ͘Δ ඇಉظͰCJUNBQΛϩʔυ͢Δ ݟ։͖࣌ϖʔδϩʔυ
RenderBitmapTask: bitmapੜ ݟ։͖ରԠͷͨΊͪΐͬͱෳࡶ جຊ1EG3FOEFSFSSFOEFS ΛݺͿ͚ͩ
RenderBitmapTask ϑϨʔϜ͔ͭͬͯ;Θͬͱग़ݱͤ͞Δ
Ͳ͜·Ͱ࠷దԽ͖͔͢ • 3ϖʔδ (දࣔϖʔδ+લޙϖʔδʣͷʮ४උʯ͕1ϑ ϨʔϜ(16ms)ҎԼͳΒेߴ • 1ϑϨʔϜҎԼͰͷ࠷దԽઅిޮՌ͘Β͍ • bitmapੜ30msͱ300msͰUXʹͦΕ΄Ͳҧ͍ͳ͍ •
500msΛ͑ΔΑ͏ͳΒ࠷దԽ͖͚ͩ͢ͲɺͦΕҎ Լʹ͢Δྗ͋·Γҙຯ͕ͳ͍
File #2 طಡཧ͍ͨ͠
طಡཧ • ΞϓϦͷॻ੶͝ͱʹɺͲ͜·ͰಡΜ͔ͩه ͍ͨ͠ • ViewPager#getCurrentItem() ͰҐஔΛऔಘ • 1ը໘1ϖʔδͷ࣌؆୯ɺ1ը໘2ϖʔ δʢݟ։͖ʣͷͱ͖
• ʮॻ੶σʔλͰͷҐஔʯʹม͢Δඞཁ͕͋Δ
ʮҐஔʯʹؔ͢Δ໋໊نଇ • ໋໊نଇΛͭ͘Βͳ͍ͱࢮ͵ • ViewPagerͷݱࡏ: position • ॻ੶σʔλͰͷҐஔ: pageIndex •
Ϧϑϩʔͷ͜ͱߟ͑ͳ͍ͷͱ͢Δ
QPSUSBJUͷͱ͖ͦͷ·· JT1PSUSBJU ͡Όͳ͍ͱ͍͚ͳ͍ͷ 7JFX1BHFSͷόάͱࢥΘΕΔ MBOETDBQF ݟ։͖ ͷͱ͖ ഒͯ͠දࢴͷΛҾ͘ ਖ਼֬ʹٯͷมΛߦ͏ 7JFX1BHFSͷҐஔ͔Βॻ੶Ґஔʹม
ॻ੶Ґஔ͔Β7JFX1BHFSͷҐஔʹม
File #3 ViewPager͕ࢥ͍௨Γʹಈ͍ ͯ͘Εͳ͍ΜͰ͢…
VPΛӈ͔ΒࠨʹҠಈͤ͞Δ • ViewPagerleft-to-rightͳͷͰɺright-to-left ͷॻ੶Λදࣔ͢Δͱ͖ʹͦͷ··͏ͱࢮ͵ • …ͷͰRVPͱ͍͏ϥΠϒϥϦΛ࡞ͬͨ • https://github.com/gfx/ReversibleViewPager • rvp.setReversed(true)
͢Δ͚ͩʂ
ViewPagerͰϐϯνΠϯɾΞτ͢ ΔͱIllegalArgumentException • ViewPagerͷόάͬΆ͍ • https://code.google.com/p/android/issues/detail?id=64553 • ViewPager Λܧঝͯ͠ super.onInterceptTouchEvent()
ͷྫ֎ΛѲΓ௵ ͤʂ • RVP͜ͷରԠ͕ೖ͍ͬͯΔ
VP#onSavedInstanceState() • ը໘ճస࣌ʹঢ়ଶΛอଘ͢Δ࣌ʹݺΕΔ • configuration͔ΒͱΕΔorientation͕ʮݱࡏͷ σόΠεͷํʯͰͳ͘ʮ͜Ε͔Β͔͏ํʯ ʹͳΔ • ͦ͜Ͱલड़ͷ !isPortrait()
ʹͳͬͨ • ͜Εਖ਼͍͠ͷ͔…ಈ͍ͯΔ͚Ͳ…
VP#onCreateView()ͱঢ়ଶ෮ؼ • onSavedInstanceState()Ͱอଘͨ͠ঢ়ଶΛ෮ؼͤ͞Δ • ͔͠͠ɺonCreateView()Ͱ vp.setCurrentItem() ͯ͠ແ ࢹ͞ΕΔʂʂʂ • onCreateView()ͷ͋ͱʹFragment͕view
(VPؚΉ) ͷঢ় ଶΛ෮ؼ͢Δ͔ΒɺΒ͍͠ • onCreateView()Ͱঢ়ଶΛಡΈͩ͠ɺonResume()Ͱ vp.setCurrentItem()͢Δ͜ͱʹͨ͠
RVPͷ՝ • RVPΛᘳʹ࣮͢Δͷ͕͍͠ • v1.0.2࣌Ͱ PagerTitleStrip ͱͷڠௐ͕͏ ·͍͔͘ͳ͍όά͕͋Δ • RTLAOSPଆͰରԠͯ͘͠ΕΔͱخ͍͠
• ໘ͳ͜ͱGoogleͷΤϯδχΞʹ͍ͤͨ
That's all.
https://github.com/gfx/ TinyPdfReader