add nomedia adding/removing at directory view

app/src/main/kotlin/com/simplemobiletools/gallery/adapters/DirectoryAdapter.kt

@@ -23,9 +23,7 @@ import com.simplemobiletools.gallery.R
 import com.simplemobiletools.gallery.activities.SimpleActivity
 import com.simplemobiletools.gallery.dialogs.CopyDialog
 import com.simplemobiletools.gallery.dialogs.RenameDirectoryDialog
-import com.simplemobiletools.gallery.extensions.config
+import com.simplemobiletools.gallery.extensions.*
-import com.simplemobiletools.gallery.extensions.containsNoMedia
-import com.simplemobiletools.gallery.extensions.createSelector
 import com.simplemobiletools.gallery.models.Directory
 import kotlinx.android.synthetic.main.directory_item.view.*
 import kotlinx.android.synthetic.main.directory_tmb.view.*
@@ -172,6 +170,15 @@ class DirectoryAdapter(val activity: SimpleActivity, val dirs: MutableList<Direc
     }
 
     private fun toggleFoldersVisibility(hide: Boolean) {
+        val paths = getSelectedPaths()
+        for (path in paths) {
+            if (hide) {
+                activity.addNoMedia(path)
+            } else {
+                activity.removeNoMedia(path)
+            }
+        }
+
         listener?.refreshItems()
         actMode?.finish()
     }

app/src/main/kotlin/com/simplemobiletools/gallery/extensions/activity.kt

@@ -10,12 +10,12 @@ import android.view.KeyCharacterMap
 import android.view.KeyEvent
 import android.view.View
 import android.view.ViewConfiguration
-import com.simplemobiletools.commons.extensions.getMimeType
+import com.simplemobiletools.commons.extensions.*
-import com.simplemobiletools.commons.extensions.toast
 import com.simplemobiletools.commons.helpers.*
 import com.simplemobiletools.gallery.BuildConfig
 import com.simplemobiletools.gallery.R
 import com.simplemobiletools.gallery.activities.SimpleActivity
+import com.simplemobiletools.gallery.helpers.NOMEDIA
 import com.simplemobiletools.gallery.helpers.REQUEST_EDIT_IMAGE
 import com.simplemobiletools.gallery.helpers.REQUEST_SET_WALLPAPER
 import com.simplemobiletools.gallery.models.Medium
@@ -142,3 +142,37 @@ fun AppCompatActivity.hideSystemUI() {
             View.SYSTEM_UI_FLAG_FULLSCREEN or
             View.SYSTEM_UI_FLAG_IMMERSIVE
 }
+
+fun SimpleActivity.addNoMedia(path: String) {
+    val file = File(path, NOMEDIA)
+    if (file.exists())
+        return
+
+    if (needsStupidWritePermissions(path)) {
+        if (!isShowingPermDialog(file)) {
+            getFileDocument(path, config.treeUri)?.createFile("", NOMEDIA)
+        }
+    } else {
+        file.createNewFile()
+    }
+    scanFile(file) {}
+}
+
+fun SimpleActivity.removeNoMedia(path: String) {
+    val file = File(path, NOMEDIA)
+    if (!file.exists())
+        return
+
+    if (!file.delete() && !tryFastDocumentDelete(file)) {
+        if (needsStupidWritePermissions(path)) {
+            if (!isShowingPermDialog(file)) {
+                getFileDocument(path, config.treeUri)?.apply {
+                    if (isFile) {
+                        delete()
+                    }
+                }
+            }
+        }
+        scanFile(file) {}
+    }
+}