FLUTTER 21 Dismissible (Tutorial Flutter Bahasa Indonesia)

Summary

In this tutorial, the presenter explains how to use the dismissible widget in Flutter to create interactive list items that can be swiped to delete. The video covers the basics of Dialogs, with a focus on how to implement dismissible elements in a list view. The presenter demonstrates how to add swiping functionality, show a confirmation dialog before deleting an item, and customize the swipe direction and appearance. The tutorial also highlights using Future and Navigator to manage deletion actions and ensure the confirmation process is completed properly before removing an item.

Takeaways

• 😀 The tutorial focuses on implementing the `Dismissible` widget in Flutter for creating swipeable list items.
• 😀 `Dismissible` allows each list item to be swiped left or right to remove it, enhancing user interaction.
• 😀 Before using `Dismissible`, it's important to understand Flutter's `Dialog` widget, as the functionality is based on dialogs.
• 😀 The script demonstrates using `ListView.builder` to generate a list of items, which can be individually dismissed.
• 😀 Each list item is wrapped in the `Dismissible` widget, requiring a unique key (usually the item's index).
• 😀 You can customize the swipe direction in `Dismissible`, such as enabling swipes only from left to right.
• 😀 A red background and a delete icon are added to provide visual feedback when an item is being swiped.
• 😀 The script adds a confirmation dialog that asks the user for confirmation before actually deleting an item.
• 😀 The confirmation dialog includes two buttons: 'Yes' to confirm and 'No' to cancel the action.
• 😀 When the user confirms the deletion, the item is removed from the list. If canceled, the swipe action is reversed.
• 😀 The tutorial provides detailed code for setting up both the `Dismissible` widget and the confirmation dialog using Flutter’s `showDialog()` method.

Q & A

What is the main purpose of using the Dismissible widget in Flutter?

The Dismissible widget in Flutter is used to create a swipe-to-dismiss functionality for list items, allowing users to swipe an item off the screen to remove or perform some action on it.

How does the Dismissible widget work with ListView.builder?

The Dismissible widget can be wrapped around list items created by ListView.builder to make each item swipeable. The key property of the Dismissible widget is typically the item's index, ensuring that each item has a unique identifier.

What is the purpose of the 'onDismissed' callback in the Dismissible widget?

The 'onDismissed' callback is triggered when the user swipes an item in the Dismissible widget. It is typically used to handle actions like showing a confirmation dialog or deleting the item from the list.

How can you configure the swipe direction for the Dismissible widget?

You can configure the swipe direction of the Dismissible widget by using the 'direction' property. The available options are from left to right (start to end) or from right to left (end to start).

Why is a confirmation dialog necessary when using the Dismissible widget?

A confirmation dialog is necessary to prevent accidental deletions or actions when an item is swiped away. It ensures that the user confirms their action before proceeding with the deletion or removal of the item.

How can you implement a confirmation dialog in Flutter when deleting an item?

A confirmation dialog can be implemented using the 'showDialog' function along with an AlertDialog widget. The dialog presents two options: 'Yes' to confirm the deletion and 'No' to cancel the action.

What is the role of the 'Navigator.pop(context)' method in the confirmation dialog?

The 'Navigator.pop(context)' method is used to close the dialog. It is called when the user selects either 'Yes' or 'No' in the confirmation dialog, returning control back to the main screen or widget.

What happens when the 'Yes' button in the confirmation dialog is pressed?

When the 'Yes' button is pressed, the item is removed from the list, and the changes are reflected in the UI. This action is performed inside the 'setState' function to trigger a UI update.

Can the Dismissible widget be used with other Flutter widgets aside from ListView?

Yes, the Dismissible widget can be used with any other widget that requires swipe-to-dismiss functionality. It is not limited to ListView and can be wrapped around other types of containers or widgets.

How does the 'onDismissed' callback relate to the swipe action in the Dismissible widget?

The 'onDismissed' callback is fired once the swipe action reaches a certain point, indicating that the item is being dismissed. It is an ideal place to handle the logic of what happens after the item is swiped away, such as triggering the confirmation dialog.