Flutter Widgets → Flutter GridView – Camposha

Flutter Widgets

Flutter Widgets

Flutter Widgets

Flutter GridView

Flutter GridView Tutorial and Example.

We will see how to render items in a GridView in this tutorial and how to handle item click events.

A GridView is a scrollable, 2D array of widgets.

The main axis direction of a grid is the direction in which it scrolls (the scrollDirection).

The most commonly used grid layouts are GridView.count, which creates a layout with a fixed number of tiles in the cross axis, andGridView.extent, which creates a layout with tiles that have a maximum cross-axis extent. A custom SliverGridDelegate can produce an arbitrary 2D arrangement of children, including arrangements that are unaligned or overlapping.

To create a grid with a large (or infinite) number of children, use the GridView.builder constructor with either a SliverGridDelegateWithFixedCrossAxisCount or a SliverGridDelegateWithMaxCrossAxisExtent for the gridDelegate.

To use a custom SliverChildDelegate, use GridView.custom.

To create a linear array of children, use a ListView.

To control the initial scroll offset of the scroll view, provide a controller with its ScrollController.initialScrollOffset property set.

new GridView.count(
  primary: false,
  padding: const EdgeInsets.all(20.0),
  crossAxisSpacing: 10.0,
  crossAxisCount: 2,
  children: <Widget>[
    const Text('He'd have you all unravel at the'),
    const Text('Heed not the rabble'),
    const Text('Sound of screams but the'),
    const Text('Who scream'),
    const Text('Revolution is coming...'),
    const Text('Revolution, they...'),
  ],
)

Video tutorial(ProgrammingWizards TV Channel)

Well we have a video tutorial as an alternative to this. If you prefer tutorials like this one then it would be good you subscribe to our YouTube channel.

Basically we have a TV for programming where do daily tutorials especially android.

Let’s look a flutter GridView example with onClick.

Flutter Simple GridView with OnClick Example

This is a simple flutter gridview example to display items from a flutter fixed-length list, otherwise known as an array in other languages. Obviously we write our app in Dart programming language.

If the user clicks a single cardview, a CupertinoAlertDialog will be rendered with the clicked item.

The dialog will have some text and icon.

Here are the files we explore:

  1. pubspec.yaml
  2. lib/main.dart
(a). pubspec.yaml
name: mr_simple_gridview
description: A new Flutter project.

dependencies:
  flutter:
    sdk: flutter

  # The following adds the Cupertino Icons font to your application.
  # Use with the CupertinoIcons class for iOS style icons.
  cupertino_icons: ^0.1.2

dev_dependencies:
  flutter_test:
    sdk: flutter

# The following section is specific to Flutter.
flutter:

  # The following line ensures that the Material Icons font is
  # included with your application, so that you can use the icons in
  # the material Icons class.
  uses-material-design: true
(b). main.dart

This is where we write our flutter code in dart programming language. In Dart it is very common to write several classes in a single file. So this simple file will have three classes.

Importing Packages in Flutter/Dart

But first we need to import some packages and we do that using the import keyword in dart.

import 'package:flutter/material.dart';
import 'package:flutter/cupertino.dart';

Here are the packages we are importing:

  1. material.dart : will give us material design widgets and theme.
  2. cupertino.dart : Will give us CupertinoAlertDialog as well as cupertino icons.
Creating classes in Flutter/Dart

In Dart like in most C style programming languages you create a class using the class keyword. Classes are encapsulation mechanism in Object Oriented Programming languages.

In this case we create three classes:
1.class MyApp extends StatelessWidget {..}

  1. class Home extends StatefulWidget {..}
  2. class _HomeState extends State<Home> {..}
import 'package:flutter/material.dart';
import 'package:flutter/cupertino.dart';

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      title: 'Flutter GridView',
      home: new Home(),
      theme: new ThemeData(primaryColor: Colors.deepOrange),
    );
  }
}

class Home extends StatefulWidget {
  @override
  _HomeState createState() => new _HomeState();
}

class _HomeState extends State<Home> {

  @override
  Widget build(BuildContext context) {
    var spacecrafts = ["James Web","Enterprise","Hubble","Kepler","Juno","Casini","Columbia","Challenger","Huygens","Galileo","Apollo","Spitzer","WMAP","Swift","Atlantis"];
    var myGridView = new GridView.builder(
      itemCount: spacecrafts.length,
      gridDelegate: new SliverGridDelegateWithFixedCrossAxisCount(crossAxisCount: 3),
      itemBuilder: (BuildContext context, int index) {
        return new GestureDetector(
          child: new Card(
            elevation: 5.0,
            child: new Container(
              alignment: Alignment.centerLeft,
              margin: new EdgeInsets.only(top: 10.0, bottom: 10.0,left: 10.0),
              child: new Text(spacecrafts[index]),
            ),
          ),
          onTap: () {
            showDialog(
                barrierDismissible: false,
                context: context,
                child: new CupertinoAlertDialog(
                  title: new Column(
                    children: <Widget>[
                      new Text("GridView"),
                      new Icon(
                        Icons.favorite,
                        color: Colors.red,
                      ),
                    ],
                  ),
                  content: new Text( spacecrafts[index]),
                  actions: <Widget>[
                    new FlatButton(
                        onPressed: () {
                          Navigator.of(context).pop();
                        },
                        child: new Text("OK"))
                  ],
                ));
          },
        );
      },
    );

    return new Scaffold(
      appBar: new AppBar(
          title: new Text("Flutter GridView")
      ),
      body: myGridView,
    );
  }
}
void main() {
  runApp(new MyApp());
}

Download

You can download full source code below.

No. Location Link
1. GitHub Direct Download
2. GitHub Browse

Best Regards,

 

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