43 lines
1.1 KiB
Dart
43 lines
1.1 KiB
Dart
// @dart=2.9
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import 'package:flutter/material.dart';
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class PlaceHolderWidget extends StatelessWidget {
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const PlaceHolderWidget(
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this.count,
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this.columns, {
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Key key,
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}) : super(key: key);
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final int count, columns;
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static final _gridViewCache = <String, GridView>{};
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@override
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Widget build(BuildContext context) {
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final key = _getCacheKey(count, columns);
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if (!_gridViewCache.containsKey(key)) {
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_gridViewCache[key] = GridView.builder(
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padding: const EdgeInsets.all(0),
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shrinkWrap: true,
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physics: const NeverScrollableScrollPhysics(),
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itemBuilder: (context, index) {
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return Container(
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margin: const EdgeInsets.all(2.0),
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color: Colors.grey[900],
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);
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},
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itemCount: count,
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gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
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crossAxisCount: columns,
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),
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);
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}
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return _gridViewCache[key];
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}
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String _getCacheKey(int totalCount, int columns) {
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return totalCount.toString() + ":" + columns.toString();
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}
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}
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