implement the sorting by date taken

app/src/main/kotlin/com/simplemobiletools/gallery/dialogs/ChangeSortingDialog.kt

@@ -5,7 +5,7 @@ import android.app.AlertDialog
 import android.content.DialogInterface
 import android.view.LayoutInflater
 import android.view.View
-import com.simplemobiletools.gallery.*
+import com.simplemobiletools.gallery.R
 import com.simplemobiletools.gallery.helpers.*
 import kotlinx.android.synthetic.main.dialog_change_sorting.view.*
 
@@ -40,11 +40,12 @@ class ChangeSortingDialog(val activity: Activity, val isDirectorySorting: Boolea
         val sortingRadio = view.sorting_dialog_radio_sorting
         var sortBtn = sortingRadio.sorting_dialog_radio_name
 
-        if (currSorting and SORT_BY_DATE_MODIFIED != 0) {
+        if (currSorting and SORT_BY_SIZE != 0) {
-            sortBtn = sortingRadio.sorting_dialog_radio_date
-        } else if (currSorting and SORT_BY_SIZE != 0) {
             sortBtn = sortingRadio.sorting_dialog_radio_size
-        }
+        } else if (currSorting and SORT_BY_DATE_MODIFIED != 0) {
+            sortBtn = sortingRadio.sorting_dialog_radio_last_modified
+        } else if (currSorting and SORT_BY_DATE_TAKEN != 0)
+            sortBtn = sortingRadio.sorting_dialog_radio_date_taken
         sortBtn.isChecked = true
     }
 
@@ -62,8 +63,9 @@ class ChangeSortingDialog(val activity: Activity, val isDirectorySorting: Boolea
         val sortingRadio = view.sorting_dialog_radio_sorting
         var sorting = when (sortingRadio.checkedRadioButtonId) {
             R.id.sorting_dialog_radio_name -> SORT_BY_NAME
-            R.id.sorting_dialog_radio_date -> SORT_BY_DATE_MODIFIED
+            R.id.sorting_dialog_radio_size -> SORT_BY_SIZE
-            else -> SORT_BY_SIZE
+            R.id.sorting_dialog_radio_last_modified -> SORT_BY_DATE_MODIFIED
+            else -> SORT_BY_DATE_TAKEN
         }
 
         if (view.sorting_dialog_radio_order.checkedRadioButtonId == R.id.sorting_dialog_radio_descending) {

app/src/main/kotlin/com/simplemobiletools/gallery/models/Directory.kt

@@ -2,6 +2,7 @@ package com.simplemobiletools.gallery.models
 
 import com.simplemobiletools.gallery.helpers.SORT_BY_DATE_MODIFIED
 import com.simplemobiletools.gallery.helpers.SORT_BY_NAME
+import com.simplemobiletools.gallery.helpers.SORT_BY_SIZE
 import com.simplemobiletools.gallery.helpers.SORT_DESCENDING
 
 class Directory(val path: String, val thumbnail: String, val name: String, var mediaCnt: Int, val date_modified: Long, val date_taken: Long,
@@ -18,6 +19,13 @@ class Directory(val path: String, val thumbnail: String, val name: String, var m
         var res: Int
         if (sorting and SORT_BY_NAME != 0) {
             res = name.toLowerCase().compareTo(other.name.toLowerCase())
+        } else if (sorting and SORT_BY_SIZE != 0) {
+            res = if (size == other.size)
+                0
+            else if (size > other.size)
+                1
+            else
+                -1
         } else if (sorting and SORT_BY_DATE_MODIFIED != 0) {
             res = if (date_modified == other.date_modified)
                 0
@@ -26,9 +34,9 @@ class Directory(val path: String, val thumbnail: String, val name: String, var m
             else
                 -1
         } else {
-            res = if (size == other.size)
+            res = if (date_taken == other.date_taken)
                 0
-            else if (size > other.size)
+            else if (date_taken > other.date_taken)
                 1
             else
                 -1

app/src/main/kotlin/com/simplemobiletools/gallery/models/Medium.kt

@@ -2,6 +2,7 @@ package com.simplemobiletools.gallery.models
 
 import com.simplemobiletools.gallery.helpers.SORT_BY_DATE_MODIFIED
 import com.simplemobiletools.gallery.helpers.SORT_BY_NAME
+import com.simplemobiletools.gallery.helpers.SORT_BY_SIZE
 import com.simplemobiletools.gallery.helpers.SORT_DESCENDING
 import java.io.Serializable
 
@@ -23,6 +24,13 @@ class Medium(val name: String, var path: String, val isVideo: Boolean, val date_
         var res: Int
         if (sorting and SORT_BY_NAME != 0) {
             res = name.toLowerCase().compareTo(other.name.toLowerCase())
+        } else if (sorting and SORT_BY_SIZE != 0) {
+            res = if (size == other.size)
+                0
+            else if (size > other.size)
+                1
+            else
+                -1
         } else if (sorting and SORT_BY_DATE_MODIFIED != 0) {
             res = if (date_modified == other.date_modified)
                 0
@@ -31,9 +39,9 @@ class Medium(val name: String, var path: String, val isVideo: Boolean, val date_
             else
                 -1
         } else {
-            res = if (size == other.size)
+            res = if (date_taken == other.date_taken)
                 0
-            else if (size > other.size)
+            else if (date_taken > other.date_taken)
                 1
             else
                 -1

app/src/main/res/layout/dialog_change_sorting.xml

@@ -28,7 +28,15 @@
                 android:text="@string/name"/>
 
             <RadioButton
-                android:id="@+id/sorting_dialog_radio_date"
+                android:id="@+id/sorting_dialog_radio_size"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:paddingBottom="@dimen/medium_padding"
+                android:paddingTop="@dimen/medium_padding"
+                android:text="@string/size"/>
+
+            <RadioButton
+                android:id="@+id/sorting_dialog_radio_last_modified"
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
                 android:paddingBottom="@dimen/medium_padding"
@@ -36,12 +44,13 @@
                 android:text="@string/last_modified"/>
 
             <RadioButton
-                android:id="@+id/sorting_dialog_radio_size"
+                android:id="@+id/sorting_dialog_radio_date_taken"
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
                 android:paddingBottom="@dimen/medium_padding"
                 android:paddingTop="@dimen/medium_padding"
-                android:text="@string/size"/>
+                android:text="@string/date_taken"/>
+
         </RadioGroup>
 
         <ImageView