Exception is thrown with empty message when trp_hourFormat attribute has invalid value.

[pelmenstar1]

If invalid value is passed to enum property, we will get a build error:
AAPT: error: '420' is incompatible with attribute trp_hourFormat (attr) enum [FORMAT_SYSTEM=0, FORMAT_12=1, FORMAT_24=2]

Code:

<LinearLayout 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"
    tools:context=".MainActivity">

    <nl.joery.timerangepicker.TimeRangePicker
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:trp_hourFormat="420" />

</LinearLayout>

But, nevertheless, if we pass a reference to integer with invalid value, we won't get any build error and code compiles successfully:
ints.xml

<resources>
    <integer name="some_invalid_value">3</integer>
</resources>

activity_main.xml

<LinearLayout 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"
    tools:context=".MainActivity">

    <nl.joery.timerangepicker.TimeRangePicker
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:trp_hourFormat="@integer/some_invalid_value" />

</LinearLayout>

Full code

In runtime, we will get exception with no message:

     Caused by: java.lang.IllegalArgumentException
        at nl.joery.timerangepicker.TimeRangePicker$HourFormat$Companion.fromId(TimeRangePicker.kt:1160)
        at nl.joery.timerangepicker.TimeRangePicker.initAttributes(TimeRangePicker.kt:147)
        at nl.joery.timerangepicker.TimeRangePicker.<init>(TimeRangePicker.kt:114)
        at nl.joery.timerangepicker.TimeRangePicker.<init>(TimeRangePicker.kt:39)
        at nl.joery.timerangepicker.TimeRangePicker.<init>(TimeRangePicker.kt)

Library tries to handle such cases but unsuccessfully:

TimeRangePicker/timerangepicker/src/main/java/nl/joery/timerangepicker/TimeRangePicker.kt

Lines 135 to 140 in a5c73db

	hourFormat = HourFormat.fromId(
	attr.getInt(
	R.styleable.TimeRangePicker_trp_hourFormat,
	_hourFormat.id
	)
	) ?: _hourFormat // Sets public property to determine 24 / 12 format automatically

TimeRangePicker/timerangepicker/src/main/java/nl/joery/timerangepicker/TimeRangePicker.kt

Lines 1081 to 1086 in a5c73db

	fun fromId(id: Int): HourFormat? {
	for (f in values()) {
	if (f.id == id) return f
	}
	throw IllegalArgumentException()
	}

Method fromId never returns null, but throws exception with empty message on invalid value, but initAttributes expects that fromId returns null and assignes default value (HourFormat.FORMAT_12) if returned enum value is null.

So, what's expected behavior? To leave default value, or to throw exception. If the last one, it's better to throw exception with some message like 'Invalid attribute value(trp_hourFormat=value)'

[pelmenstar1]

The same problem with trp_clockFace

TimeRangePicker/timerangepicker/src/main/java/nl/joery/timerangepicker/TimeRangePicker.kt

Lines 224 to 229 in a5c73db

	_clockFace = ClockFace.fromId(
	attr.getInt(
	R.styleable.TimeRangePicker_trp_clockFace,
	_clockFace.id
	)
	) ?: _clockFace

TimeRangePicker/timerangepicker/src/main/java/nl/joery/timerangepicker/TimeRangePicker.kt

Lines 1095 to 1100 in a5c73db

	fun fromId(id: Int): ClockFace? {
	for (f in values()) {
	if (f.id == id) return f
	}
	throw IllegalArgumentException()
	}

[Droppers]

I think it should throw an exception with a clear message, returning null and using the default value can be unexpected behavior for the user.

I currently don't have time (this week) to make any changes.