Initial support of long press in reader

app/src/main/kotlin/org/koitharu/kotatsu/core/util/GridTouchHelper.kt

@@ -52,6 +52,23 @@ class GridTouchHelper(
 		return true
 	}
 
+	override fun onLongPress(event: MotionEvent) {
+		super.onLongPress(event)
+		val xIndex = (event.rawX * 2f / width).roundToInt()
+		val yIndex = (event.rawY * 2f / height).roundToInt()
+		listener.onGridLongTouch(
+			when(xIndex) {
+				1 -> {
+					when (yIndex) {
+						1 -> AREA_CENTER
+						else -> -1
+					}
+				}
+				else -> -1
+			}
+		)
+	}
+
 	companion object {
 
 		const val AREA_CENTER = 1
@@ -65,6 +82,8 @@ class GridTouchHelper(
 
 		fun onGridTouch(area: Int)
 
+		fun onGridLongTouch(area: Int)
+
 		fun onProcessTouch(rawX: Int, rawY: Int): Boolean
 	}
 }

app/src/main/kotlin/org/koitharu/kotatsu/reader/ui/ReaderActivity.kt

@@ -24,6 +24,7 @@ import androidx.core.view.updateLayoutParams
 import androidx.core.view.updatePadding
 import androidx.lifecycle.Lifecycle
 import androidx.lifecycle.lifecycleScope
+import com.google.android.material.dialog.MaterialAlertDialogBuilder
 import com.google.android.material.snackbar.Snackbar
 import dagger.hilt.android.AndroidEntryPoint
 import kotlinx.coroutines.Dispatchers
@@ -43,6 +44,7 @@ import org.koitharu.kotatsu.core.ui.widgets.ZoomControl
 import org.koitharu.kotatsu.core.util.GridTouchHelper
 import org.koitharu.kotatsu.core.util.IdlingDetector
 import org.koitharu.kotatsu.core.util.ShareHelper
+import org.koitharu.kotatsu.core.util.ext.DIALOG_THEME_CENTERED
 import org.koitharu.kotatsu.core.util.ext.hasGlobalPoint
 import org.koitharu.kotatsu.core.util.ext.isAnimationsEnabled
 import org.koitharu.kotatsu.core.util.ext.isRtl
@@ -204,6 +206,10 @@ class ReaderActivity :
 		controlDelegate.onGridTouch(area, viewBinding.container)
 	}
 
+	override fun onGridLongTouch(area: Int) {
+		controlDelegate.onGridLongTouch(area, viewBinding.container)
+	}
+
 	override fun onProcessTouch(rawX: Int, rawY: Int): Boolean {
 		return if (
 			rawX <= gestureInsets.left ||
@@ -336,6 +342,13 @@ class ReaderActivity :
 		setUiIsVisible(!viewBinding.appbarTop.isVisible)
 	}
 
+	override fun viewDialog() {
+		MaterialAlertDialogBuilder(this, DIALOG_THEME_CENTERED)
+			.setMessage("Called dialog on long press")
+			.setPositiveButton(R.string.got_it, null)
+			.show()
+	}
+
 	override fun isReaderResumed(): Boolean {
 		val reader = readerManager.currentReader ?: return false
 		return reader.isResumed && supportFragmentManager.fragments.lastOrNull() === reader

app/src/main/kotlin/org/koitharu/kotatsu/reader/ui/ReaderControlDelegate.kt

@@ -69,6 +69,15 @@ class ReaderControlDelegate(
 		}
 	}
 
+	fun onGridLongTouch(area: Int, view: View) {
+		when (area) {
+			GridTouchHelper.AREA_CENTER -> {
+				listener.viewDialog()
+				view.playSoundEffect(SoundEffectConstants.CLICK)
+			}
+		}
+	}
+
 	fun onKeyDown(keyCode: Int, @Suppress("UNUSED_PARAMETER") event: KeyEvent?): Boolean = when (keyCode) {
 		KeyEvent.KEYCODE_VOLUME_UP -> if (isVolumeKeysSwitchEnabled) {
 			listener.switchPageBy(-1)
@@ -155,6 +164,8 @@ class ReaderControlDelegate(
 
 		fun switchPageBy(delta: Int)
 
+		fun viewDialog()
+
 		fun scrollBy(delta: Int, smooth: Boolean): Boolean
 
 		fun toggleUiVisibility()