Update sdk and migrate to kotlin and androidx

app/build.gradle

@@ -1,13 +1,15 @@
 apply plugin: 'com.android.application'
+apply plugin: 'kotlin-android'
+apply plugin: 'kotlin-android-extensions'
 
 android {
-    compileSdkVersion 25
-    buildToolsVersion '25.0.3'
+    compileSdkVersion 29
+    buildToolsVersion '29.0.1'
 
     defaultConfig {
         applicationId "com.snatik.storage.sample"
         minSdkVersion 14
-        targetSdkVersion 25
+        targetSdkVersion 29
         versionCode 1
         versionName "1.0"
     }
@@ -20,8 +22,13 @@ android {
 }
 
 dependencies {
-    compile fileTree(include: ['*.jar'], dir: 'libs')
-    compile project(':storage')
-    compile 'com.android.support.constraint:constraint-layout:1.0.2'
-    compile 'com.android.support:design:25.3.1'
+    implementation fileTree(include: ['*.jar'], dir: 'libs')
+    implementation project(':storage')
+    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
+    implementation 'com.google.android.material:material:1.0.0'
+    implementation "androidx.core:core-ktx:1.0.2"
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
+}
+repositories {
+    mavenCentral()
 }

app/src/main/java/com/snatik/storage/app/FilesAdapter.kt

@@ -0,0 +1,77 @@
+package com.snatik.storage.app
+
+import android.content.Context
+import androidx.recyclerview.widget.RecyclerView
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.ImageView
+import android.widget.TextView
+
+import com.snatik.storage.Storage
+
+import java.io.File
+
+/**
+ * Created by sromku on June, 2017.
+ */
+class FilesAdapter(context: Context) : RecyclerView.Adapter<RecyclerView.ViewHolder>() {
+
+    private var mFiles: List<File>? = null
+    private var mListener: OnFileItemListener? = null
+    private val mStorage: Storage = Storage(context)
+
+    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
+        val view = LayoutInflater.from(parent.context).inflate(R.layout.file_line_view, parent, false)
+        return FileViewHolder(view)
+    }
+
+    override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
+        val file = mFiles!![position]
+        val fileViewHolder = holder as FileViewHolder
+        fileViewHolder.itemView.setOnClickListener { mListener!!.onClick(file) }
+        fileViewHolder.itemView.setOnLongClickListener {
+            mListener!!.onLongClick(file)
+            true
+        }
+        fileViewHolder.mName.text = file.name
+        fileViewHolder.mIcon.setImageResource(getIcon(file))
+        if (file.isDirectory) {
+            fileViewHolder.mSize.visibility = View.VISIBLE
+            fileViewHolder.mSize.text = ""
+        } else {
+            fileViewHolder.mSize.visibility = View.VISIBLE
+            fileViewHolder.mSize.text = mStorage.getReadableSize(file)
+        }
+
+    }
+
+    private fun getIcon(file: File) = if (file.isDirectory)
+        R.drawable.ic_folder_primary_24dp
+    else
+        R.drawable.ic_file_primary_24dp
+
+    override fun getItemCount(): Int {
+        return if (mFiles != null) mFiles!!.size else 0
+    }
+
+    fun setFiles(files: List<File>?) {
+        mFiles = files
+    }
+
+    fun setListener(listener: OnFileItemListener) {
+        mListener = listener
+    }
+
+    internal class FileViewHolder(v: View) : RecyclerView.ViewHolder(v) {
+        var mName: TextView = v.findViewById<View>(R.id.name) as TextView
+        var mSize: TextView = v.findViewById<View>(R.id.size) as TextView
+        var mIcon: ImageView = v.findViewById<View>(R.id.icon) as ImageView
+    }
+
+    interface OnFileItemListener {
+        fun onClick(file: File)
+
+        fun onLongClick(file: File)
+    }
+}

app/src/main/java/com/snatik/storage/app/GenericFileProvider.kt

@@ -0,0 +1,8 @@
+package com.snatik.storage.app
+
+import androidx.core.content.FileProvider
+
+/**
+ * Created by sromku on July, 2017.
+ */
+class GenericFileProvider : FileProvider()

app/src/main/java/com/snatik/storage/app/Helper.kt

@@ -0,0 +1,35 @@
+package com.snatik.storage.app
+
+import com.google.android.material.snackbar.Snackbar
+import android.view.View
+
+/**
+ * Created by sromku on June, 2017.
+ */
+object Helper {
+
+    fun showSnackbar(message: String, root: View) {
+        Snackbar.make(root, message, Snackbar.LENGTH_SHORT).show()
+    }
+
+    fun fileExt(url: String): String? {
+        var newUrl = url
+        if (newUrl.indexOf("?") > -1) {
+            newUrl = newUrl.substring(0, newUrl.indexOf("?"))
+        }
+        return if (newUrl.lastIndexOf(".") == -1) {
+            null
+        } else {
+            var ext = newUrl.substring(newUrl.lastIndexOf(".") + 1)
+            if (ext.indexOf("%") > -1) {
+                ext = ext.substring(0, ext.indexOf("%"))
+            }
+            if (ext.indexOf("/") > -1) {
+                ext = ext.substring(0, ext.indexOf("/"))
+            }
+            ext.toLowerCase()
+
+        }
+    }
+
+}