workaround: photoview gestures not working correctly in ViewPager2

Author: mardous

app/src/main/java/com/simplified/wsstatussaver/views/PhotoViewWrapper.kt

@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2024 Christians Martínez Alvarado
+ *
+ * Licensed under the GNU General Public License v3
+ *
+ * This is free software: you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by
+ * the Free Software Foundation either version 3 of the License, or (at your option) any later version.
+ *
+ * This software is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ */
+package com.simplified.wsstatussaver.views
+
+import android.content.Context
+import android.util.AttributeSet
+import android.view.MotionEvent
+import android.widget.FrameLayout
+
+/**
+ * https://github.com/Baseflow/PhotoView/issues/708#issuecomment-1116960531
+ */
+class PhotoViewWrapper @JvmOverloads constructor(context: Context, attrs: AttributeSet? = null) :
+    FrameLayout(context, attrs) {
+
+    private var isParentInterceptionDisallowed = false
+
+    override fun requestDisallowInterceptTouchEvent(disallowIntercept: Boolean) {
+        isParentInterceptionDisallowed = disallowIntercept
+        if (disallowIntercept) {
+            // PhotoView wants to disallow parent interception, let it be.
+            parent.requestDisallowInterceptTouchEvent(true) // don't ban wrapper itself
+        } else {
+            // PhotoView wants to allow parent interception, we need to re-check it.
+        }
+    }
+
+    override fun onInterceptTouchEvent(ev: MotionEvent): Boolean {
+        // always false when up or cancel event,
+        // which will allow parent interception normally.
+        val isMultiTouch = ev.pointerCount > 1
+
+        // re-check if it's multi touch
+        parent.requestDisallowInterceptTouchEvent(isParentInterceptionDisallowed || isMultiTouch)
+        return false
+    }
+}

app/src/main/res/layout/fragment_image.xml

@@ -12,7 +12,7 @@
   ~ See the GNU General Public License for more details.
   -->
 
-<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<com.simplified.wsstatussaver.views.PhotoViewWrapper xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
@@ -38,4 +38,4 @@
 
     </FrameLayout>
 
-</FrameLayout>
+</com.simplified.wsstatussaver.views.PhotoViewWrapper>