titles() function to add titles to pages.

.gitignore

@@ -0,0 +1,10 @@
+*.iml
+/.idea
+.gradle
+/local.properties
+/.idea/workspace.xml
+/.idea/libraries
+.DS_Store
+/build
+/captures
+.externalNativeBuild

README.md

@@ -9,14 +9,22 @@ viewPager.apply {
 
     fragmentPagerAdapter(pageCount = 3, fragmentManager = supportFragmentManager) {
 
-        createItems { position ->
+        pages { position ->
             when (position) {
                 0 -> InputFragment()
                 1 -> OutputFragment()
                 2 -> AboutFragment()
                 else -> throw Exception("¯\\_(ツ)_/¯")
             }
         }
+
+        titles { position ->
+            when (position) {
+                0 -> "Entries"
+                1 -> "Results"
+                2 -> "About Us"
+                else -> "¯\\_(ツ)_/¯"
+        }
     }
 
     onPageSelected { position ->

library/src/main/java/mhashim6/android/viewpagerdsl/FragmentPagerAdapterDSL.kt

@@ -11,14 +11,21 @@ import android.support.v4.view.ViewPager
 
 class FragmentPagerAdapterDSL(var pageCount: Int = 0, fragmentManager: FragmentManager) : FragmentPagerAdapter(fragmentManager) {
 
-	private lateinit var onCreateItem: (position: Int) -> Fragment
+	private var onCreateItem: (position: Int) -> Fragment = throw RuntimeException("pages() is not called")
+	private var onCreateTitle: (position: Int) -> CharSequence = { "" }
 
-	fun createItems(action: (position: Int) -> Fragment) {
+	fun pages(action: (position: Int) -> Fragment) {
 		onCreateItem = action
 	}
 
+	/**default implementation returns empty string */
+	fun titles(action: (position: Int) -> CharSequence) {
+		onCreateTitle = action
+	}
+
 	override fun getItem(position: Int) = onCreateItem.invoke(position)
 	override fun getCount() = pageCount
+	override fun getPageTitle(position: Int): CharSequence = onCreateTitle.invoke(position)
 }
 
 //Extensions