Add doc comment to extension functions

Author: enginebai

base/src/main/java/com/enginebai/base/extensions/EditTextExt.kt

@@ -10,6 +10,11 @@ import io.reactivex.Observable
 import io.reactivex.Single
 import io.reactivex.subjects.PublishSubject
 
+/**
+ * Invoke the listener when afterTextChanged() method is called.
+ *
+ * @return TextWatcher remember to remove when no longer use it anymore.
+ */
 fun EditText.textChanged(listener: (String) -> Unit): TextWatcher {
 	val textWatcher = object : TextWatcher {
 		override fun afterTextChanged(s: Editable?) {
@@ -48,7 +53,12 @@ private class TextChangeWatcher(private var publisher: PublishSubject<String>? =
 	}
 }
 
-
+/**
+ * Validate the input text and display error when it's invalid.
+ * @param [errorMessage] error message to display
+ * @param [validator] the predicate to validate input.
+ *  @return TextWatcher remember to remove when no longer use it anymore.
+ */
 fun EditText.validate(errorMessage: String, validator: (String) -> Boolean): TextWatcher {
 	fun showErrorIfInvalid(s: String) {
 		this.error = if (validator(s)) null else errorMessage
@@ -59,10 +69,28 @@ fun EditText.validate(errorMessage: String, validator: (String) -> Boolean): Tex
 	return this.textChanged { showErrorIfInvalid(it) }
 }
 
+/**
+ * Validate if input is valid email, and invoke either valid or invalid listener.
+ * @return TextWatcher remember to remove when no longer use it anymore.
+ */
+fun EditText.validateEmail(validListener: (String) -> Unit, invalidListener: (String) -> Unit = {}): TextWatcher {
+	return this.textChanged {
+		if (it.isValidEmail()) validListener(it)
+		else invalidListener(it)
+	}
+}
+
+/**
+ * Validate if input is valid email, and display error if invalid. * @return TextWatcher remember to remove when no longer use it anymore.
+ * @return TextWatcher remember to remove when no longer use it anymore.
+ */
 fun EditText.validateEmail(errorMessage: String): TextWatcher {
 	return validate(errorMessage) { it.isValidEmail() }
 }
 
+/**
+ * Validate if input is valid email and return result as stream.
+ */
 fun EditText.validateEmail(): Single<Boolean> {
 	return Single.fromObservable(this.textChanged()).flatMap {
 		Single.just(it.toString().isValidEmail())

base/src/main/java/com/enginebai/base/extensions/StringExt.kt

@@ -3,6 +3,6 @@ package com.enginebai.base.extensions
 import android.util.Patterns
 import androidx.core.util.PatternsCompat
 
-fun String.isValidEmail(): Boolean {
-	return PatternsCompat.EMAIL_ADDRESS.matcher(this).matches()
+fun String?.isValidEmail(): Boolean {
+	return PatternsCompat.EMAIL_ADDRESS.matcher(this ?: "").matches()
 }

base/src/main/java/com/enginebai/base/extensions/TextViewExt.kt

@@ -3,11 +3,17 @@ package com.enginebai.base.extensions
 import android.view.View
 import android.widget.TextView
 
+/**
+ * Set view visible when text is not null or blank, else set view gone.
+ */
 fun TextView.setTextWithExistence(s: String?) {
 	s?.let { this.text = it }
 	setExistence(!s.isNullOrBlank())
 }
 
+/**
+ * Set view visible when text is not null or blank, else set view invisible.
+ */
 fun TextView.setTextWithVisibility(s: String?) {
 	s?.let { this.text = it }
 	setVisible(!s.isNullOrBlank())

base/src/main/java/com/enginebai/base/extensions/ViewExt.kt

@@ -10,10 +10,10 @@ import androidx.core.content.ContextCompat
 
 /**
  * Prevent multiple click in a short period of time. Default interval is 1500 milli-second.
- * @param listener: The click listener
  * @param intervalInMillis: The time interval to trigger next click events.
+ * @param listener: The click listener
  */
-inline fun View.debounceClick(crossinline listener: (view: View) -> Unit, intervalInMillis: Int = 1500) {
+inline fun View.debounceClick(intervalInMillis: Int = 1500, crossinline listener: (view: View) -> Unit) {
 	var lastClick = 0L
 	setOnClickListener {
 		val diff = System.currentTimeMillis() - lastClick
@@ -27,28 +27,43 @@ inline fun View.debounceClick(crossinline listener: (view: View) -> Unit, interv
 //
 // visibility
 //
+/**
+ * Set visible or invisible of view.
+ */
 fun View.setVisible(visible: Boolean) {
 	visibility = if (visible) View.VISIBLE else View.INVISIBLE
 }
 
+/**
+ * Set visible or gone of view.
+ */
 fun View.setExistence(exist: Boolean) {
 	visibility = if (exist) View.VISIBLE else View.GONE
 }
 
+/**
+ * Set view visible when matching the given [predicate]
+ */
 inline fun View.showIf(predicate: () -> Boolean): View {
 	if (visibility != View.VISIBLE && predicate()) {
 		visibility = View.VISIBLE
 	}
 	return this
 }
 
+/**
+ * Set view invisible when matching the given [predicate]
+ */
 inline fun View.hideIf(predicate: () -> Boolean): View {
 	if (visibility != View.INVISIBLE && predicate()) {
-		visibility = View.VISIBLE
+		visibility = View.INVISIBLE
 	}
 	return this
 }
 
+/**
+ * Set view gone when matching the given [predicate]
+ */
 inline fun View.goneIf(predicate: () -> Boolean): View {
 	if (visibility != View.GONE && predicate()) {
 		visibility = View.GONE