MainActivity.kt<\/strong><\/p>\npackage com.charlezz.galleryapp.ui\r\nimport android.Manifest\r\nimport android.content.pm.PackageManager\r\nimport android.os.Bundle\r\nimport android.support.v4.app.ActivityCompat\r\nimport android.support.v7.app.AppCompatActivity\r\nimport com.charlezz.galleryapp.R\r\nimport io.reactivex.rxkotlin.Observables\r\nimport io.reactivex.rxkotlin.toObservable\r\nclass MainActivity : AppCompatActivity() {\r\n val TAG = MainActivity::class.java.simpleName\r\n val permissions = arrayOf(\r\n Manifest.permission.READ_EXTERNAL_STORAGE\r\n )\r\n override fun onCreate(savedInstanceState: Bundle?) {\r\n super.onCreate(savedInstanceState)\r\n setContentView(R.layout.activity_main)\r\n permissions.toObservable()\r\n .filter {\r\n ActivityCompat.checkSelfPermission(this, it) != PackageManager.PERMISSION_GRANTED\r\n }\r\n .toList()\r\n .map {\r\n permissions.sortedArray()\r\n }\r\n .subscribe { permissionList: Array<String>?, _: Throwable? ->\r\n permissionList?.let {\r\n ActivityCompat.requestPermissions(this, it, 0)\r\n }\r\n }\r\n }\r\n override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<out String>, grantResults: IntArray) {\r\n super.onRequestPermissionsResult(requestCode, permissions, grantResults)\r\n Observables.zip(\r\n permissions.toObservable(),\r\n grantResults.toObservable())\r\n .filter {\r\n it.second != PackageManager.PERMISSION_GRANTED\r\n }.count()\r\n .subscribe { permissionCount: Long?, t2: Throwable? ->\r\n if (permissionCount == 0L) {\/\/zero means all permissions granted\r\n supportFragmentManager.beginTransaction()\r\n .replace(R.id.container, GalleryFragment.newInstance())\r\n .commit()\r\n } else {\r\n finish()\r\n }\r\n }\r\n }\r\n}<\/pre>\npermission \uc744 \uc694\uccad\ud560 \ubc30\uc5f4(permissions)\uc744 \ubbf8\ub9ac \ub9cc\ub4ed\ub2c8\ub2e4. \uac24\ub7ec\ub9ac \uc571\uc758 \uacbd\uc6b0 READ_EXTERNAL_STORAGE\ub9cc \uc788\uc73c\uba74 \ub429\ub2c8\ub2e4.
\n\ud37c\ubbf8\uc158 \ubc30\uc5f4\uc744 \uc635\uc800\ubc84\ube14\ub85c \ubcc0\uacbd\ud558\uc5ec \ud604\uc7ac \ud5c8\uac00\ub418\uc9c0 \uc54a\uc740 \ud37c\ubbf8\uc158\uc744 \ucd94\ub824\ub0b8 \ub4a4 requestPermissions\uba54\uc18c\ub4dc\ub97c \uc774\uc6a9\ud558\uc5ec \uad8c\ud55c\uc744 \uc694\uccad\ud558\uace0 \uc788\uc2b5\ub2c8\ub2e4.
\n\uc694\uccad\ub41c \uad8c\ud55c\uc740 \uc0ac\uc6a9\uc790\ub85c \ud558\uc5ec\uae08 \ud5c8\uc6a9 \ub610\ub294 \uac70\ubd80\ub97c \ud560 \uc218 \uc788\uc73c\uba70 \uc804\ubd80 \ud5c8\uc6a9\ud560 \uc2dc \uc5d0\ub9cc \ub2e4\uc74c \ub3d9\uc791( Fragment \u00a0\ub744\uc6b0\uae30) \uc744 \uc218\ud589\ud558\ub3c4\ub85d \ud558\uace0, \ud55c\uac1c\ub77c\ub3c4 \uad8c\ud55c\uc744 \uac70\ubd80 \ud588\ub2e4\uba74 finish() \ub85c \uc571\uc744 \uc885\ub8cc\ud558\ub294 \ubaa8\uc2b5\uc785\ub2c8\ub2e4.
\n\u00a0
\nGalleryFragment.kt<\/strong><\/p>\nclass GalleryFragment : Fragment() {\r\n val TAG = GalleryFragment::class.java.simpleName\r\n companion object {\r\n fun newInstance() = GalleryFragment()\r\n }\r\n lateinit var binding: FragmentGalleryBinding\r\n val adapter = GalleryAdapter()\r\n override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {\r\n binding = FragmentGalleryBinding.inflate(inflater, container, false)\r\n return binding.root\r\n }\r\n override fun onViewCreated(view: View, savedInstanceState: Bundle?) {\r\n super.onViewCreated(view, savedInstanceState)\r\n binding.recyclerView.adapter = adapter\r\n binding.recyclerView.layoutManager = GridLayoutManager(context, 3)\r\n }\r\n override fun onResume() {\r\n super.onResume()\r\n adapter.clearItems()\r\n getItemsObservable()\r\n .observeOn(AndroidSchedulers.mainThread())\r\n .subscribe {\r\n adapter.addItem(it, true)\r\n }\r\n }\r\n fun getItemsObservable(): Observable<GalleryData> {\r\n val cursor = context?.contentResolver?.query(\r\n MediaStore.Images.Media.EXTERNAL_CONTENT_URI,\r\n arrayOf(\r\n MediaStore.Images.Media.DISPLAY_NAME,\r\n MediaStore.Images.Media.DATA\r\n ),\r\n null,\r\n null,\r\n null)\r\n cursor?.let {\r\n return Observable.fromIterable(RxCursorIterable.from(cursor))\r\n .subscribeOn(Schedulers.io())\r\n .doAfterNext {\r\n if (it.isLast) {\r\n it.close()\r\n }\r\n }\r\n .map { c ->\r\n val name = c.getString(c.getColumnIndex(MediaStore.Images.Media.DISPLAY_NAME))\r\n val path = c.getString(c.getColumnIndex(MediaStore.Images.Media.DATA))\r\n GalleryData(name, path)\r\n }\r\n }\r\n return Observable.empty<GalleryData>()\r\n }\r\n}<\/pre>\ngetItemObservable\uba54\uc18c\ub4dc\ub97c \ubcf4\uba74 \ube44\ub3d9\uae30\uc801\uc73c\ub85c \uc774\ubbf8\uc9c0 \uc774\ub984\uacfc \uacbd\ub85c\ub97c GalleryData\ub77c\ub294 \ub370\uc774\ud130\ud074\ub798\uc2a4\uc5d0 \ubc1c\ud589\ud558\uac8c \ub418\uc5b4\uc788\ub2e4.
\nonResume()\uc5d0\uc11c\ub294 mainThread\uc2a4\ucf00\uc904\ub7ec\ub97c \uc774\uc6a9\ud558\uc5ec \uad6c\ub3c5\uc744 \ud558\uace0 \uc788\ub2e4. (View\ub97c \uac74\ub4dc\ub9b4\uc218 \uc788\ub294\uac74 \uc624\ub85c\uc9c0 \uba54\uc778\uc4f0\ub808\ub4dc \ubfd0!)
\n\u00a0
\nGalleryAdapter.kt<\/strong><\/p>\nclass GalleryAdapter : RecyclerView.Adapter<GalleryAdapter.GalleryViewHolder>() {\r\n val items = ArrayList<GalleryData>()\r\n override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): GalleryViewHolder {\r\n val inflater = LayoutInflater.from(parent.context)\r\n val binding = VhGalleryBinding.inflate(\r\n inflater,\r\n parent,\r\n false)\r\n return GalleryViewHolder(binding)\r\n }\r\n fun addItem(item: GalleryData, update: Boolean) {\r\n items.add(item)\r\n if (update) {\r\n notifyItemChanged(items.lastIndex)\r\n }\r\n }\r\n fun clearItems() {\r\n items.clear()\r\n notifyDataSetChanged()\r\n }\r\n override fun getItemCount(): Int {\r\n return items.size\r\n }\r\n override fun onBindViewHolder(holder: GalleryViewHolder, position: Int) {\r\n holder.binding.galleryData = items[position]\r\n holder.binding.executePendingBindings()\r\n }\r\n class GalleryViewHolder(binding: VhGalleryBinding) : RecyclerView.ViewHolder(binding.root) {\r\n val binding = binding\r\n }\r\n}<\/pre>\naddItem\uba54\uc18c\ub4dc\ub97c \ud1b5\ud558\uc5ec \ub9ac\uc2a4\ud2b8\uc5d0 \uc774\ubbf8\uc9c0\ub97c \ud558\ub098\uc529 \ucd94\uac00 \ud558\uace0 \uc788\ub2e4.
\nonBindViewHolder \uc5d0\uc11c\ub294 \ub370\uc774\ud130 \ubc14\uc778\ub529\uc744 \ub77c\uc774\ube0c\ub7ec\ub9ac\ub97c \ud65c\uc6a9\ud558\uc5ec \ub370\uc774\ud130\ub97c \uc8fc\uc785\ud558\uace0 \uc788\ub294 \ubaa8\uc2b5\uc774\ub2e4.<\/p>\n
\nReactive Programing(1) – \ub9ac\uc561\ud2f0\ube0c \ud504\ub85c\uadf8\ub798\ubc0d \uac1c\ub150\uc7a1\uae30<\/a>
\nReactive Programing(2) \u2013 Reactive Operator<\/a>
\nReactive Programing(3) \u2013 Reactive Operator<\/a>
\nReactive Programing(4) \u2013 Scheduler<\/a>
\nReactive Programing(5) \u2013 \uc548\ub4dc\ub85c\uc774\ub4dc\uc5d0\uc11c\uc758 RxJava \ud65c\uc6a9<\/p>\n
\n <\/p>\n","protected":false},"excerpt":{"rendered":"
Reactive Programing(1) – \ub9ac\uc561\ud2f0\ube0c \ud504\ub85c\uadf8\ub798\ubc0d \uac1c\ub150\uc7a1\uae30 Reactive Programing(2) \u2013 Reactive Operator Reactive Programing(3) \u2013 Reactive Operator Reactive Programing(4) \u2013 Scheduler Reactive Programing(5) \u2013 \uc548\ub4dc\ub85c\uc774\ub4dc\uc5d0\uc11c\uc758 RxJava \ud65c\uc6a9 \uc548\ub4dc\ub85c\uc774\ub4dc\uc5d0\uc11c RxJava2 \uc0ac\uc6a9\ud558\uae30 \u00a0 \uc790\ubc14\ub294 \ud568\uc218\ud615 \ud504\ub85c\uadf8\ub798\ubc0d\uc744 \uc81c\ub300\ub85c \uc9c0\uc6d0\ud558\uc9c0 \ubabb\ud558\uace0 \uc788\uc73c\uba70, \uc5ec\uc804\ud788 Side Effect(\ubd80\uc218\ud6a8\uacfc)\ub97c \uc644\ubcbd\ud558\uac8c \uc81c\uac70\ud558\uc9c0 \ubabb\ud588\ub2e4. \uc774\ub7ec\ud55c \uc774\uc720\ub85c \uc548\ub4dc\ub85c\uc774\ub4dc\uc5d0\uc11c RxJava2\ub97c \uc0ac\uc6a9\ud560 \uc218 \uc788\ub294 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"inline_featured_image":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0},"categories":[7],"tags":[],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/charlezz.com\/index.php?rest_route=\/wp\/v2\/posts\/299"}],"collection":[{"href":"https:\/\/charlezz.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/charlezz.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/charlezz.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/charlezz.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=299"}],"version-history":[{"count":1,"href":"https:\/\/charlezz.com\/index.php?rest_route=\/wp\/v2\/posts\/299\/revisions"}],"predecessor-version":[{"id":1381,"href":"https:\/\/charlezz.com\/index.php?rest_route=\/wp\/v2\/posts\/299\/revisions\/1381"}],"wp:attachment":[{"href":"https:\/\/charlezz.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=299"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/charlezz.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=299"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/charlezz.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=299"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
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