add a toggle for preventing the phone from sleeping

app/build.gradle

@@ -43,7 +43,7 @@ android {
 }
 
 dependencies {
-    implementation 'com.simplemobiletools:commons:3.13.15'
+    implementation 'com.simplemobiletools:commons:3.13.16'
     implementation 'me.grantland:autofittextview:0.2.1'
 
     testImplementation 'junit:junit:4.12'

app/src/main/kotlin/com/simplemobiletools/calculator/activities/MainActivity.kt

@@ -6,6 +6,7 @@ import android.os.Bundle
 import android.view.Menu
 import android.view.MenuItem
 import android.view.View
+import android.view.WindowManager
 import com.simplemobiletools.calculator.BuildConfig
 import com.simplemobiletools.calculator.R
 import com.simplemobiletools.calculator.extensions.config
@@ -69,12 +70,20 @@ class MainActivity : SimpleActivity(), Calculator {
         if (storedTextColor != config.textColor) {
             updateViewColors(calculator_holder, config.textColor)
         }
+
+        if (config.preventPhoneFromSleeping) {
+            window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)
+        }
+
         vibrateOnButtonPress = config.vibrateOnButtonPress
     }
 
     override fun onPause() {
         super.onPause()
         storeStateVariables()
+        if (config.preventPhoneFromSleeping) {
+            window.clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)
+        }
     }
 
     override fun onCreateOptionsMenu(menu: Menu): Boolean {

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

@@ -23,6 +23,7 @@ class SettingsActivity : SimpleActivity() {
         setupUseEnglish()
         setupAvoidWhatsNew()
         setupVibrate()
+        setupPreventPhoneFromSleeping()
         updateTextColors(settings_scrollview)
     }
 
@@ -57,4 +58,12 @@ class SettingsActivity : SimpleActivity() {
             config.vibrateOnButtonPress = settings_vibrate.isChecked
         }
     }
+
+    private fun setupPreventPhoneFromSleeping() {
+        settings_prevent_phone_from_sleeping.isChecked = config.preventPhoneFromSleeping
+        settings_prevent_phone_from_sleeping_holder.setOnClickListener {
+            settings_prevent_phone_from_sleeping.toggle()
+            config.preventPhoneFromSleeping = settings_prevent_phone_from_sleeping.isChecked
+        }
+    }
 }

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

@@ -92,5 +92,28 @@
                 android:text="@string/vibrate_on_button_press"/>
 
         </RelativeLayout>
+
+        <RelativeLayout
+            android:id="@+id/settings_prevent_phone_from_sleeping_holder"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="@dimen/medium_margin"
+            android:background="?attr/selectableItemBackground"
+            android:paddingBottom="@dimen/activity_margin"
+            android:paddingLeft="@dimen/normal_margin"
+            android:paddingRight="@dimen/normal_margin"
+            android:paddingTop="@dimen/activity_margin">
+
+            <com.simplemobiletools.commons.views.MySwitchCompat
+                android:id="@+id/settings_prevent_phone_from_sleeping"
+                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/prevent_phone_from_sleeping"/>
+
+        </RelativeLayout>
     </LinearLayout>
 </ScrollView>