add an option to change media instantly by clicking on screen sides

app/src/main/kotlin/com/simplemobiletools/gallery/activities/PhotoVideoActivity.kt

@@ -24,6 +24,7 @@ import kotlinx.android.synthetic.main.fragment_holder.*
 import java.io.File
 
 open class PhotoVideoActivity : SimpleActivity(), ViewPagerFragment.FragmentListener {
+
     private var mMedium: Medium? = null
     private var mIsFullScreen = false
     private var mIsFromGallery = false
@@ -158,4 +159,8 @@ open class PhotoVideoActivity : SimpleActivity(), ViewPagerFragment.FragmentList
     }
 
     override fun videoEnded() = false
+
+    override fun goToPrevItem() {}
+
+    override fun goToNextItem() {}
 }

app/src/main/kotlin/com/simplemobiletools/gallery/activities/SettingsActivity.kt

@@ -55,6 +55,7 @@ class SettingsActivity : SimpleActivity() {
         setupKeepLastModified()
         setupShowInfoBubble()
         setupOneFingerZoom()
+        setupAllowInstantChange()
         setupShowExtendedDetails()
         setupManageExtendedDetails()
         updateTextColors(settings_holder)
@@ -286,6 +287,14 @@ class SettingsActivity : SimpleActivity() {
         }
     }
 
+    private fun setupAllowInstantChange() {
+        settings_allow_instant_change.isChecked = config.allowInstantChange
+        settings_allow_instant_change_holder.setOnClickListener {
+            settings_allow_instant_change.toggle()
+            config.allowInstantChange = settings_allow_instant_change.isChecked
+        }
+    }
+
     private fun setupShowExtendedDetails() {
         settings_show_extended_details.isChecked = config.showExtendedDetails
         settings_show_extended_details_holder.setOnClickListener {

app/src/main/kotlin/com/simplemobiletools/gallery/activities/ViewPagerActivity.kt

@@ -3,7 +3,6 @@ package com.simplemobiletools.gallery.activities
 import android.animation.Animator
 import android.animation.ValueAnimator
 import android.app.Activity
-import android.content.Context
 import android.content.Intent
 import android.content.pm.ActivityInfo
 import android.content.res.Configuration
@@ -820,11 +819,20 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
     }
 
     override fun videoEnded(): Boolean {
-        if (mIsSlideshowActive)
+        if (mIsSlideshowActive) {
             swipeToNextMedium()
+        }
         return mIsSlideshowActive
     }
 
+    override fun goToPrevItem() {
+        view_pager.setCurrentItem(view_pager.currentItem - 1, false)
+    }
+
+    override fun goToNextItem() {
+        view_pager.setCurrentItem(view_pager.currentItem + 1, false)
+    }
+
     private fun checkSystemUI() {
         if (mIsFullScreen) {
             hideSystemUI()

app/src/main/kotlin/com/simplemobiletools/gallery/fragments/PhotoFragment.kt

@@ -49,7 +49,12 @@ class PhotoFragment : ViewPagerFragment() {
     lateinit var medium: Medium
 
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View {
-        view = inflater.inflate(R.layout.pager_photo_item, container, false) as ViewGroup
+        view = (inflater.inflate(R.layout.pager_photo_item, container, false) as ViewGroup).apply {
+            subsampling_view.setOnClickListener { photoClicked() }
+            gif_view.setOnClickListener { photoClicked() }
+            instant_prev_item.setOnClickListener { listener?.goToPrevItem() }
+            instant_next_item.setOnClickListener { listener?.goToNextItem() }
+        }
 
         if (!isFragmentVisible && activity is PhotoActivity) {
             isFragmentVisible = true
@@ -88,11 +93,8 @@ class PhotoFragment : ViewPagerFragment() {
         }
 
         isFullscreen = activity!!.window.decorView.systemUiVisibility and View.SYSTEM_UI_FLAG_FULLSCREEN == View.SYSTEM_UI_FLAG_FULLSCREEN
-        view.subsampling_view.setOnClickListener { photoClicked() }
-        view.gif_view.setOnClickListener { photoClicked() }
         loadImage()
         checkExtendedDetails()
-
         wasInit = true
 
         return view
@@ -109,6 +111,10 @@ class PhotoFragment : ViewPagerFragment() {
         if (wasInit && (context!!.config.showExtendedDetails != storedShowExtendedDetails || context!!.config.extendedDetails != storedExtendedDetails)) {
             checkExtendedDetails()
         }
+
+        val allowInstantChange = context!!.config.allowInstantChange
+        view.instant_prev_item.beVisibleIf(allowInstantChange)
+        view.instant_next_item.beVisibleIf(allowInstantChange)
     }
 
     override fun setMenuVisibility(menuVisible: Boolean) {

app/src/main/kotlin/com/simplemobiletools/gallery/fragments/VideoFragment.kt

@@ -66,8 +66,12 @@ class VideoFragment : ViewPagerFragment(), SurfaceHolder.Callback, SeekBar.OnSee
     lateinit var medium: Medium
 
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
-        mView = inflater.inflate(R.layout.pager_video_item, container, false)
+        mView = inflater.inflate(R.layout.pager_video_item, container, false).apply {
-        mTimeHolder = mView!!.video_time_holder
+            instant_prev_item.setOnClickListener { listener?.goToPrevItem() }
+            instant_next_item.setOnClickListener { listener?.goToNextItem() }
+            mTimeHolder = video_time_holder
+        }
+
         medium = arguments!!.getSerializable(MEDIUM) as Medium
 
         // setMenuVisibility is not called at VideoActivity (third party intent)
@@ -90,8 +94,15 @@ class VideoFragment : ViewPagerFragment(), SurfaceHolder.Callback, SeekBar.OnSee
     override fun onResume() {
         super.onResume()
         activity!!.updateTextColors(mView!!.video_holder)
-        mView!!.video_volume_controller.beVisibleIf(context!!.config.allowVideoGestures)
+        val allowVideoGestures = context!!.config.allowVideoGestures
-        mView!!.video_brightness_controller.beVisibleIf(context!!.config.allowVideoGestures)
+        val allowInstantChange = context!!.config.allowInstantChange
+        mView!!.apply {
+            video_volume_controller.beVisibleIf(allowVideoGestures)
+            video_brightness_controller.beVisibleIf(allowVideoGestures)
+
+            instant_prev_item.beVisibleIf(allowInstantChange)
+            instant_next_item.beVisibleIf(allowInstantChange)
+        }
 
         if (context!!.config.showExtendedDetails != mStoredShowExtendedDetails || context!!.config.extendedDetails != mStoredExtendedDetails) {
             checkExtendedDetails()

app/src/main/kotlin/com/simplemobiletools/gallery/fragments/ViewPagerFragment.kt

@@ -16,6 +16,10 @@ abstract class ViewPagerFragment : Fragment() {
         fun fragmentClicked()
 
         fun videoEnded(): Boolean
+
+        fun goToPrevItem()
+
+        fun goToNextItem()
     }
 
     fun getMediumExtendedDetails(medium: Medium): String {

app/src/main/kotlin/com/simplemobiletools/gallery/helpers/Config.kt

@@ -172,6 +172,10 @@ class Config(context: Context) : BaseConfig(context) {
         get() = prefs.getBoolean(ONE_FINGER_ZOOM, false)
         set(oneFingerZoom) = prefs.edit().putBoolean(ONE_FINGER_ZOOM, oneFingerZoom).apply()
 
+    var allowInstantChange: Boolean
+        get() = prefs.getBoolean(ALLOW_INSTANT_CHANGE, false)
+        set(allowInstantChange) = prefs.edit().putBoolean(ALLOW_INSTANT_CHANGE, allowInstantChange).apply()
+
     private fun getDirectoryColumnsField(): String {
         val isPortrait = context.resources.configuration.orientation == Configuration.ORIENTATION_PORTRAIT
         return if (isPortrait) {

app/src/main/kotlin/com/simplemobiletools/gallery/helpers/Constants.kt

@@ -44,6 +44,7 @@ val SHOW_EXTENDED_DETAILS = "show_extended_details"
 val EXTENDED_DETAILS = "extended_details"
 val LAST_FILE_CLEANUP = "last_file_cleanup"
 val ONE_FINGER_ZOOM = "one_finger_zoom"
+val ALLOW_INSTANT_CHANGE = "allow_instant_change"
 
 // slideshow
 val SLIDESHOW_INTERVAL = "slideshow_interval"

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

@@ -477,6 +477,26 @@
 
         </RelativeLayout>
 
+        <RelativeLayout
+            android:id="@+id/settings_allow_instant_change_holder"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="@dimen/medium_margin"
+            android:background="?attr/selectableItemBackground"
+            android:padding="@dimen/activity_margin">
+
+            <com.simplemobiletools.commons.views.MySwitchCompat
+                android:id="@+id/settings_allow_instant_change"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:background="@null"
+                android:clickable="false"
+                android:paddingLeft="@dimen/medium_margin"
+                android:paddingStart="@dimen/medium_margin"
+                android:text="@string/allow_instant_change"/>
+
+        </RelativeLayout>
+
         <RelativeLayout
             android:id="@+id/settings_show_extended_details_holder"
             android:layout_width="match_parent"

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

@@ -31,4 +31,16 @@
         android:visibility="gone"
         tools:text="My image\nAnother line"/>
 
+    <RelativeLayout
+        android:id="@+id/instant_prev_item"
+        android:layout_width="@dimen/instant_change_bar_width"
+        android:layout_height="match_parent"/>
+
+    <RelativeLayout
+        android:id="@+id/instant_next_item"
+        android:layout_width="@dimen/instant_change_bar_width"
+        android:layout_height="match_parent"
+        android:layout_alignParentEnd="true"
+        android:layout_alignParentRight="true"/>
+
 </RelativeLayout>

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

@@ -25,6 +25,18 @@
         android:layout_width="@dimen/video_side_slider_width"
         android:layout_height="match_parent"/>
 
+    <RelativeLayout
+        android:id="@+id/instant_prev_item"
+        android:layout_width="@dimen/instant_change_bar_width"
+        android:layout_height="match_parent"/>
+
+    <RelativeLayout
+        android:id="@+id/instant_next_item"
+        android:layout_width="@dimen/instant_change_bar_width"
+        android:layout_height="match_parent"
+        android:layout_alignParentEnd="true"
+        android:layout_alignParentRight="true"/>
+
     <ImageView
         android:id="@+id/video_play_outline"
         android:layout_width="@dimen/play_outline_size_big"

app/src/main/res/values/dimens.xml

@@ -9,5 +9,6 @@
     <dimen name="timer_padding">24dp</dimen>
     <dimen name="tmb_shadow_height">50dp</dimen>
     <dimen name="video_side_slider_width">150dp</dimen>
+    <dimen name="instant_change_bar_width">60dp</dimen>
     <dimen name="list_view_folder_thumbnail_size">72dp</dimen>
 </resources>