Kotlin extension function start activity with Intent extras
Declare:
inline fun <reified T : Activity> Context.startActivity(block: Intent.() -> Unit = {}) {
startActivity(Intent(this, T::class.java).apply(block))
}
Simple using:
startActivity<MainActivity>()
With extra
startActivity<MainActivity>{
putExtra("param 1", "Simple")
}
Here is the extension function for start activity:
inline fun <reified T : Activity> Context.openActivity(noinline extra: Intent.() -> Unit) {
val intent = Intent(this, T::class.java)
intent.extra()
startActivity(intent)
}
You can call this function like this way:
openActivity<MyActivity> {
addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
putExtra(LaBoxConstants.DEFAULT_LANDING, Default_Landing)
putExtra(HomeActivity.APP_RELAUNCH, AppReLaunched)
}
NOTE: IT IS NOT A RECOMMENDED WAY TO START ACTIVITY. USE STARTACTIVITY INSTEAD.
Instead of using a list of pairs, consider using a Bundle
. Then you can add it with putExtras(Bundle)
.
If you want to go one step ahead, you could add a lambda extension to configure the extras:
fun <T> Context.openActivity(it: Class<T>, extras: Bundle.() -> Unit = {}) {
val intent = Intent(this, it)
intent.putExtras(Bundle().apply(extras))
startActivity(intent)
}
Then you can call it as:
openActivity(MyActivity::class.java) {
putString("string.key", "string.value")
putInt("string.key", 43)
...
}
Here is the extension function for start activity:
inline fun <reified T : Activity> Context.openActivity(vararg params: Pair<String, Any>) {
val intent = Intent(this, T::class.java)
intent.putExtras(*params)
this.startActivity(intent)
}
fun Intent.putExtras(vararg params: Pair<String, Any>): Intent {
if (params.isEmpty()) return this
params.forEach { (key, value) ->
when (value) {
is Int -> putExtra(key, value)
is Byte -> putExtra(key, value)
is Char -> putExtra(key, value)
is Long -> putExtra(key, value)
is Float -> putExtra(key, value)
is Short -> putExtra(key, value)
is Double -> putExtra(key, value)
is Boolean -> putExtra(key, value)
is Bundle -> putExtra(key, value)
is String -> putExtra(key, value)
is IntArray -> putExtra(key, value)
is ByteArray -> putExtra(key, value)
is CharArray -> putExtra(key, value)
is LongArray -> putExtra(key, value)
is FloatArray -> putExtra(key, value)
is Parcelable -> putExtra(key, value)
is ShortArray -> putExtra(key, value)
is DoubleArray -> putExtra(key, value)
is BooleanArray -> putExtra(key, value)
is CharSequence -> putExtra(key, value)
is Array<*> -> {
when {
value.isArrayOf<String>() ->
putExtra(key, value as Array<String?>)
value.isArrayOf<Parcelable>() ->
putExtra(key, value as Array<Parcelable?>)
value.isArrayOf<CharSequence>() ->
putExtra(key, value as Array<CharSequence?>)
else -> putExtra(key, value)
}
}
is Serializable -> putExtra(key, value)
}
}
return this
}
Simple using:
openActivity<TestActivity>("key0" to "value0", "key1" to "value1")
A simpler approach is provided in Kotlin
Use the bundleOf()
inline fun <reified T : Activity> Context.openActivity1(vararg params: Pair<String, Any?>) {
val intent = Intent(this, T::class.java)
intent.putExtras(bundleOf(*params))
this.startActivity(intent)
}