In Kotlin, a debounce
the function limits the rate at which a particular action is performed. This can be useful in a variety of situations, such as when performing a network request or a complex calculation. By debouncing an action, you can prevent it from being performed too frequently, which can improve your app’s performance and user experience.
Here is an example of how to implement a debounce function in Kotlin:
class Debounce(private val delay: Long, val param: (String) -> Unit) {
private var debounceJob: Job? = null
@OptIn(DelicateCoroutinesApi::class)
fun offer(value: String) {
debounceJob?.cancel()
debounceJob = GlobalScope.launch {
delay(delay)
valueChanged(value)
}
}
private fun valueChanged(value: String) {
if(value.isNotEmpty())param(value)
}
}
In this code, the Debounce
class takes a delay time in milliseconds as an argument. It has a offer
method that is used to pass a new value to be debounced. The offer
method cancels any existing debounce job, and then starts a new one using the delay
time provided to the Debounce
class. After the delay time has elapsed, the valueChanged
method is called, where you can perform the desired action.
To use the Debounce
class, you can create an instance of it and then call the offer
method whenever you want to debounce a new value. For example:
val debounce = Debounce(300L)
// Offer a new value to be debounced
debounce.offer("my value")
This code will debounce the value “my value” for 300 milliseconds. After that time has elapsed, the valueChanged
method will be called and you can perform the desired action.
To use a SearchView
with a debounce function in Kotlin, you can use the following code:
// Set up the SearchView
val searchView = findViewById<SearchView>(R.id.search_view)
// Set up the debounce function
val debounce = Debounce(300L) { query ->
// Perform the search here
}
// Set an OnQueryTextListener on the SearchView to listen for changes to the query
searchView.setOnQueryTextListener(object : SearchView.OnQueryTextListener {
override fun onQueryTextChange(newText: String): Boolean {
debounce.offer(newText)
return true
}
override fun onQueryTextSubmit(query: String): Boolean {
// Handle the submission of the search query here
return true
}
})
In this code, the Debounce
the function is used to limit the rate at which the search is performed. It takes two arguments: a delay time in milliseconds, and a function to be called when the debounce time has elapsed. In this case, the function is passed the search query entered by the user, and it can be used to perform the search in the app.