I've been running through the first two parts of this

Upon enabling Dark Theme, text which was formatted (see code below) no longer appears.

The text was formatted as follows:

    private fun displayTip(tip : Double) {
        val formattedTip = NumberFormat.getCurrencyInstance().format(tip)
        binding.tipResult.text = getString(R.string.tip_amount, formattedTip)
    }

Where the string resource 'tip_amount' is defined as:

<string name="tip_amount">Tip Amount: %s</string>

Where tip is calculated as shown below:

    private fun calculateTip() {
        val serviceCost = binding.costOfService.text.toString()
        val cost = serviceCost.toDoubleOrNull()
        if (cost == null || cost == 0.0) {
            displayTip(0.0)
            return
        }
        val tipPercentage = when (binding.tipOptions.checkedRadioButtonId) {
            R.id.option_fifteen_percent -> 0.15
            R.id.option_eighteen_percent -> 0.18
            else -> 0.20
        }
        var tip = tipPercentage * cost
        if (binding.roundUpSwitch.isChecked) {
            tip = kotlin.math.ceil(tip)
        }
        displayTip(tip)
    }

I am using view bindings as instructed in the CodeLab:

    private lateinit var binding: ActivityMainBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(binding.root)
        binding.calculateButton.setOnClickListener{calculateTip()}
    }

The textview corresponding to the text that disappears upon enabling Dark Theme is below (Note: nothing appears until the user provides input and presses a button):

    <TextView
        android:id="@ id/tip_result"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:textSize="34sp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/calculate_button"
        tools:text="Tip Amount: $10" />

And finally my night/themes.xml file is below:

<resources xmlns:tools="http://schemas.android.com/tools">
    <!-- Base application theme. -->
    <style name="Theme.TipCalculator" parent="Theme.MaterialComponents.DayNight.DarkActionBar">
        <!-- Primary brand color. -->
        <item name="colorPrimary">@color/green_light</item>
        <item name="colorPrimaryVariant">@color/green</item>
        <item name="colorOnPrimary">@color/black</item>
        <!-- Secondary brand color. -->
        <item name="colorSecondary">@color/blue_light</item>
        <item name="colorSecondaryVariant">@color/blue_light</item>
        <item name="colorOnSecondary">@color/black</item>
        <!-- Status bar color. -->
        <item name="android:statusBarColor" tools:targetApi="l">?attr/colorPrimaryVariant</item>
        <!-- Customize your theme here. -->
    </style>
</resources>

Why does my semicolon and formatted text disappear when enabling Dark Theme? Why does the rest of the text in the TextView remain?

CodePudding user response：

As discussed here, the problem was that the string resource appeared differently in values/strings.xml and night/strings.xml. The string resource in night/strings.xml was not edited to use string formatting, a very simple but time consuming mistake. If you receive a similar error, I suggest checking that all string resources are defined identically across all resource files.

values/strings.xml had resource defined as:

    <string name="tip_amount">Tip Amount: %1$s</string>

While night/strings.xml defined as:

    <string name="tip_amount">Tip Amount: </string>