Nimai Walsh nimaiwalsh

Notes from Effective Kotlin: Best Practice

Safety

Limit mutability

The general rule is that one should not create unnecessary ways to mutate a state. Every way to mutate a state is a cost. Every mutation point needs to be understood and maintained. We prefer to limit mutability. General rules:

Prefer val over var.

	/**
	* Modifies a layout to ignore irs parents horizontal padding. This is useful if you have an item in a column, such as
	* a divider, that does not want to be constrained by the parents padding
	*/
	fun Modifier.ignoreHorizontalParentPadding(horizontal: Dp): Modifier {
	return this.layout { measurable, constraints ->
	val overriddenWidth = constraints.maxWidth + 2 * horizontal.roundToPx()
	val placeable = measurable.measure(constraints.copy(maxWidth = overriddenWidth))
	layout(placeable.width, placeable.height) {
	placeable.place(0, 0)

	import android.content.Context
	import java.time.temporal.ChronoField.DAY_OF_YEAR
	import java.time.temporal.ChronoField.INSTANT_SECONDS
	import java.time.temporal.ChronoField.YEAR
	import java.time.temporal.TemporalAccessor
	import java.util.Locale
	import javax.inject.Inject

	/**
	* Custom date and time formatter implementing custom formatting rules.

	import android.content.Context
	import androidx.annotation.PluralsRes
	import androidx.annotation.StringRes

	/** Provides access to localized strings and text using the resources from the application context. */
	class AndroidStringsProvider @Inject constructor(
	private val context: Context
	): StringsProvider {

	override fun get(@StringRes resId: Int): String {

	/**
	*
	* Safely run some delayed tasks in a view as they will be tied to the lifecycle.
	*
	* @param durationInMillis delay task in millisecons
	* @param dispatcher CoroutineDispatcher, defaults to Dispatchers.Main as view work is done on Main thread
	* @param block the block of work to be done
	*
	* example:
	*

	fun <T : View> Activity.bindView(viewId: Int) =
	lazy { this.findViewById<T>(viewId) }

	# Remove directories and files that aren’t in git from your own local working copy you can do so by running
	git clean -d -f -x