diff --git a/DiceRoller/.idea/deploymentTargetDropDown.xml b/DiceRoller/.idea/deploymentTargetDropDown.xml
new file mode 100644
index 0000000000000000000000000000000000000000..75666bd56303113d31f08094acaa5d7129c27b30
--- /dev/null
+++ b/DiceRoller/.idea/deploymentTargetDropDown.xml
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="deploymentTargetDropDown">
+    <targetSelectedWithDropDown>
+      <Target>
+        <type value="QUICK_BOOT_TARGET" />
+        <deviceKey>
+          <Key>
+            <type value="VIRTUAL_DEVICE_PATH" />
+            <value value="C:\Users\hp\.android\avd\Pixel_3_XL_API_29.avd" />
+          </Key>
+        </deviceKey>
+      </Target>
+    </targetSelectedWithDropDown>
+    <timeTargetWasSelectedWithDropDown value="2022-03-03T10:59:10.496023800Z" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/DiceRoller/.idea/misc.xml b/DiceRoller/.idea/misc.xml
index 36d438b92347805199e1b6a2716555270ee1f875..b3e4a97168a6060dee25fe60678a9f425481bed8 100644
--- a/DiceRoller/.idea/misc.xml
+++ b/DiceRoller/.idea/misc.xml
@@ -4,7 +4,7 @@
     <option name="filePathToZoomLevelMap">
       <map>
         <entry key="..\:/PROJECT/AndroidStudioProjects/DiceRoller/app/src/main/res/layout/activity_main.xml" value="0.7333333333333334" />
-        <entry key="..\:/PROJECT/pbd-exercise/DiceRoller/app/src/main/res/layout/activity_main.xml" value="0.3333333333333333" />
+        <entry key="..\:/PROJECT/pbd-exercise/DiceRoller/app/src/main/res/layout/activity_main.xml" value="0.1" />
       </map>
     </option>
   </component>
diff --git a/TipTime/.idea/deploymentTargetDropDown.xml b/TipTime/.idea/deploymentTargetDropDown.xml
new file mode 100644
index 0000000000000000000000000000000000000000..8b04192613223b8fd63b55d4e1a6c061d4e72792
--- /dev/null
+++ b/TipTime/.idea/deploymentTargetDropDown.xml
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="deploymentTargetDropDown">
+    <runningDeviceTargetSelectedWithDropDown>
+      <Target>
+        <type value="RUNNING_DEVICE_TARGET" />
+        <deviceKey>
+          <Key>
+            <type value="SERIAL_NUMBER" />
+            <value value="RR8MC06LCHA" />
+          </Key>
+        </deviceKey>
+      </Target>
+    </runningDeviceTargetSelectedWithDropDown>
+    <timeTargetWasSelectedWithDropDown value="2022-03-08T08:36:15.177742500Z" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/TipTime/.idea/misc.xml b/TipTime/.idea/misc.xml
index 5358d1ac0fb799f6fef8f9670b330315d83f9e57..0dc5e5c254d20fb0132a7f578acb97db680da408 100644
--- a/TipTime/.idea/misc.xml
+++ b/TipTime/.idea/misc.xml
@@ -3,7 +3,7 @@
   <component name="DesignSurface">
     <option name="filePathToZoomLevelMap">
       <map>
-        <entry key="..\:/PROJECT/pbd-exercise/TipTime/app/src/main/res/layout/activity_main.xml" value="0.1" />
+        <entry key="..\:/PROJECT/pbd-exercise/TipTime/app/src/main/res/layout/activity_main.xml" value="0.6" />
         <entry key="..\:/Users/hp/AndroidStudioProjects/TipTime/app/src/main/res/layout/activity_main.xml" value="0.1" />
       </map>
     </option>
diff --git a/TipTime/app/build.gradle b/TipTime/app/build.gradle
index 6cce0ada83fcfe545a6b513a082bf83e30baab3f..1a44ecac6191810a500c0db25b6bf7277a26b5d5 100644
--- a/TipTime/app/build.gradle
+++ b/TipTime/app/build.gradle
@@ -29,6 +29,10 @@ android {
     kotlinOptions {
         jvmTarget = '1.8'
     }
+
+    buildFeatures {
+        viewBinding true
+    }
 }
 
 dependencies {
diff --git a/TipTime/app/src/main/java/com/example/tiptime/MainActivity.kt b/TipTime/app/src/main/java/com/example/tiptime/MainActivity.kt
index 6ab37fd1f1f5ad9c9a107eec5d7b55dbcf420688..69be9d61ee29e172ac773142e0ea3b15da1f229c 100644
--- a/TipTime/app/src/main/java/com/example/tiptime/MainActivity.kt
+++ b/TipTime/app/src/main/java/com/example/tiptime/MainActivity.kt
@@ -2,10 +2,39 @@ package com.example.tiptime
 
 import androidx.appcompat.app.AppCompatActivity
 import android.os.Bundle
+import com.example.tiptime.databinding.ActivityMainBinding
+import java.text.NumberFormat
 
 class MainActivity : AppCompatActivity() {
+
+    private lateinit var binding: ActivityMainBinding
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
-        setContentView(R.layout.activity_main)
+        binding = ActivityMainBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+        binding.calculateButton.setOnClickListener{ calculateTip() }
+
     }
+
+    private fun calculateTip(){
+        val stringInTextField = binding.costOfService.text.toString()
+        val cost = stringInTextField.toDoubleOrNull()
+        if (cost == null) {
+            binding.tipResult.text = ""
+            return
+        }
+        val tipPercentage = when (binding.tipOptions.checkedRadioButtonId) {
+            R.id.option_twenty_percent -> 0.20
+            R.id.option_eighteen_percent -> 0.18
+            else -> 0.15
+        }
+        var tip = tipPercentage * cost
+        if (binding.roundUpSwitch.isChecked){
+            tip = kotlin.math.ceil(tip)
+        }
+        val formattedTip = NumberFormat.getCurrencyInstance().format(tip)
+        binding.tipResult.text = getString(R.string.tip_amount, formattedTip)
+    }
+
 }
\ No newline at end of file
diff --git a/TipTime/app/src/main/res/layout/activity_main.xml b/TipTime/app/src/main/res/layout/activity_main.xml
index 9a7985b9202312d469eaf85a601b32fd343c1863..5a30c3a04027211bceb7799aad2f9f17cd8e6d09 100644
--- a/TipTime/app/src/main/res/layout/activity_main.xml
+++ b/TipTime/app/src/main/res/layout/activity_main.xml
@@ -78,7 +78,7 @@
         android:id="@+id/tip_result"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:text="@string/tip_amount"
+        tools:text="Tip Amount: $10"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintTop_toBottomOf="@id/calculate_button" />
 
diff --git a/TipTime/app/src/main/res/values/strings.xml b/TipTime/app/src/main/res/values/strings.xml
index 7ae71439f6a96ae974ac83f8a4ac85cef7e03ade..d42b488f6ec7ca95a58f4293f6924bcbf1ce6a5f 100644
--- a/TipTime/app/src/main/res/values/strings.xml
+++ b/TipTime/app/src/main/res/values/strings.xml
@@ -7,5 +7,5 @@
     <string name="okay_service">Okay(15%)</string>
     <string name="round_up_tip">Round up tip?</string>
     <string name="calculate">Calculate</string>
-    <string name="tip_amount">Tip Amount</string>
+    <string name="tip_amount">Tip Amount: %s</string>
 </resources>
\ No newline at end of file