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lib/ui/widgets/scroll_watcher.dart

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+import 'package:flutter/material.dart';
+
+/// Scroll watcher
+///
+/// @author Pierre HUBERT
+
+typedef OnReachBottomCallback = void Function();
+
+class ScrollWatcher extends ScrollController {
+
+  // Callbacks
+  OnReachBottomCallback onReachBottom;
+
+  ScrollWatcher({this.onReachBottom}) {
+    addListener(_updatePosition);
+  }
+
+
+
+  void _updatePosition() {
+
+    // Refresh bottom position
+    if(position.pixels.floor() == position.maxScrollExtent.floor())
+      onReachBottom();
+
+  }
+}