Here is the error in the last line of the MainActivity.kt file
Format string 'tip_amount' is not a valid format string so it should not be passed to String.format
// I wrote this code while taking a course from android developer.
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() {
lateinit var binding: ActivityMainBinding
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = ActivityMainBinding.inflate(layoutInflater)
setContentView(binding.root)
binding.calculateButton.setOnClickListener { calculateTip() }
}
fun calculateTip() {
val stringInTextFiled = binding.costOfService.text.toString()
val cost = stringInTextFiled.toDouble()
val selectedId = binding.tipOptions.checkedRadioButtonId
val tipPercentage = when (selectedId) {
R.id.option_twenty_percent -> 0.20
R.id.option_eighteen_percent -> 0.18
else -> 0.15
}
var tip = tipPercentage * cost
val roundUp = binding.roundUpSwitch.isChecked
if (roundUp) {
tip = kotlin.math.ceil(tip)
}
// whether it is possible without these two lines?
val formattedTip = NumberFormat.getCurrencyInstance().format(tip)
binding.tipResult.text = getString(R.string.tip_amount, formattedTip)
}
}
// activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="16dp"
tools:context=".MainActivity">
<EditText
android:id="@+id/cost_of_service"
android:layout_width="160dp"
android:layout_height="wrap_content"
android:hint="@string/text_cost_of_service"
android:inputType="numberDecimal"
android:minHeight="48dp"
android:textColorHint="#757575"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="@+id/service_question"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/how_was_the_service"
app:layout_constraintTop_toBottomOf="@+id/cost_of_service"
app:layout_constraintStart_toStartOf="parent" />
<RadioGroup
android:id="@+id/tip_options"
android:checkedButton="@id/option_twenty_percent"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintTop_toBottomOf="@id/service_question"
app:layout_constraintStart_toStartOf="parent"
android:orientation="vertical">
<RadioButton
android:id="@+id/option_twenty_percent"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/amazing_20" />
<RadioButton
android:id="@+id/option_eighteen_percent"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/good_18" />
<RadioButton
android:id="@+id/option_fifteen_percent"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/ok_15" />
</RadioGroup>
<Switch
android:id="@+id/round_up_switch"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:checked="true"
android:minHeight="48dp"
android:text="@string/round_up_tip"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="@id/tip_options"
app:layout_constraintTop_toBottomOf="@id/tip_options"
tools:ignore="UseSwitchCompatOrMaterialXml" />
<Button
android:id="@+id/calculate_button"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:text="@string/calculate"
app:layout_constraintTop_toBottomOf="@id/round_up_switch"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent" />
<TextView
android:id="@+id/tip_result"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
tools:text="Tip Amount: $10"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toBottomOf="@id/calculate_button" />
</androidx.constraintlayout.widget.ConstraintLayout>
// values\string.xml // same resources for dark theme
<resources>
<string name="app_name">Tip Time</string>
<string name="cost_of_service">Cost of Service</string>
<string name="tip_amount">Tip Amount: %s</string>
<string name="round_up_tip">Round up tip</string>
<string name="how_was_the_service">How was the service?</string>
<string name="amazing_20">Amazing (20%)</string>
<string name="good_18">Good (18%)</string>
<string name="ok_15">OK (15%)</string>
<string name="calculate">Calculate</string>
<string name="text_cost_of_service">Cost of Service</string>
</resources>
// Unfortunately the site doesn't leak that much code, so I'm writing this text so that the question can pass. I'm sure the question is easy, I'm just new to programming and most often I can not notice the most obvious errors. I hope this time my question will pass.
