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@talenguyen
Created July 7, 2017 07:11
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Bundle binding inspired by KotterKnife
import android.app.Activity
import android.app.Fragment
import android.content.Context
import android.content.Intent
import android.os.Bundle
import android.os.Parcelable
import android.support.annotation.VisibleForTesting
import android.support.v4.app.FragmentActivity
import android.util.SparseArray
import java.util.*
import kotlin.properties.ReadOnlyProperty
import kotlin.reflect.KProperty
import android.support.v4.app.Fragment as SupportFragment
/**
* Created by Giang Nguyen on 7/5/17.
*/
inline fun <reified T : Activity> Context.intentOf(vararg extras: Pair<String, Any>): Intent {
val intent = Intent(this, T::class.java)
if (extras.isNotEmpty()) {
val bundle = bundle(*extras)
intent.putExtras(bundle)
}
return intent
}
fun bundle(vararg extras: Pair<String, Any>): Bundle {
val bundle = Bundle()
for ((key, value) in extras) {
bundle.put(key, value)
}
return bundle
}
@VisibleForTesting internal fun Bundle.put(key: String, value: Any) {
when (value) {
is Boolean -> putBoolean(key, value)
is BooleanArray -> putBooleanArray(key, value)
is Int -> putInt(key, value)
is IntArray -> putIntArray(key, value)
is Long -> putLong(key, value)
is LongArray -> putLongArray(key, value)
is Float -> putFloat(key, value)
is FloatArray -> putFloatArray(key, value)
is Double -> putDouble(key, value)
is DoubleArray -> putDoubleArray(key, value)
is String -> putString(key, value)
is CharSequence -> putCharSequence(key, value)
is Parcelable -> putParcelable(key, value)
is Array<*> -> putArray(key, value)
is ArrayList<*> -> putArrayList(key, value)
is SparseArray<*> -> @Suppress("UNCHECKED_CAST") putSparseParcelableArray(
key,
value as SparseArray<out Parcelable>?)
else -> notSupportForType(value)
}
}
private fun notSupportForType(value: Any) {
throw IllegalArgumentException("not support for ${value::class}")
}
fun Bundle.putArrayList(key: String, value: ArrayList<*>) {
if (value.isEmpty()) {
return
}
@Suppress("UNCHECKED_CAST")
when (value[0]) {
is Int -> putIntegerArrayList(key, value as ArrayList<Int>?)
is String -> putStringArrayList(key, value as ArrayList<String>?)
is CharSequence -> putCharSequenceArrayList(key, value as ArrayList<CharSequence>?)
is Parcelable -> putParcelableArrayList(key, value as ArrayList<Parcelable>?)
else -> notSupportForType(value)
}
}
private fun Bundle.putArray(key: String, value: Array<*>) {
if (value.isEmpty()) {
return
}
@Suppress("UNCHECKED_CAST")
when (value[0]) {
is String -> putStringArray(key, value as Array<out String>?)
is CharSequence -> putCharSequenceArray(key, value as Array<out String>?)
is Parcelable -> putParcelableArray(key, value as Array<out Parcelable>?)
}
}
fun <V> Activity.extra(key: String):
ReadOnlyProperty<Activity, V> = required(key, extraFinder)
fun <V> FragmentActivity.extra(key: String):
ReadOnlyProperty<FragmentActivity, V> = required(key, extraFinder)
fun <V> Fragment.arg(key: String):
ReadOnlyProperty<Fragment, V> = required(key, extraFinder)
fun <V> SupportFragment.arg(key: String):
ReadOnlyProperty<Fragment, V> = required(key, extraFinder)
private val Activity.extraFinder: Activity.(String) -> Any?
get() = { intent.extras.get(it) }
private val Fragment.extraFinder: Fragment.(String) -> Any?
get() = { arguments.get(it) }
private val SupportFragment.extraFinder: Fragment.(String) -> Any?
get() = { arguments.get(it) }
private fun keyNotFound(key: String, desc: KProperty<*>): Nothing =
throw IllegalStateException("Key $key for '${desc.name}' not found.")
@Suppress("UNCHECKED_CAST")
private fun <T, V> required(id: String, finder: T.(String) -> Any?)
= Lazy { t: T, desc -> t.finder(id) as V? ?: keyNotFound(id, desc) }
// Like Kotlin's lazy delegate but the initializer gets the target and metadata passed to it
private class Lazy<in T, out V>(
private val initializer: (T, KProperty<*>) -> V) : ReadOnlyProperty<T, V> {
private object EMPTY
private var value: Any? = EMPTY
override fun getValue(thisRef: T, property: KProperty<*>): V {
if (value == EMPTY) {
value = initializer(thisRef, property)
}
@Suppress("UNCHECKED_CAST")
return value as V
}
}
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