Скачать или смотреть How to Use DropdownButton Selections in Your Flutter To-Do List

A beginner's guide to integrating `DropdownButton` selections into a Flutter to-do list, perfect for Flutter/Dart newbies.
---
This video is based on the question https://stackoverflow.com/q/71959529/ asked by the user 'Matt Orr' ( https://stackoverflow.com/u/18853324/ ) and on the answer https://stackoverflow.com/a/71977573/ provided by the user 'Zaid Alazwi' ( https://stackoverflow.com/u/7814781/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Placing dropdownbutton selections into a to-do list

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Integrating DropdownButton Selections into Your Flutter To-Do List

If you're new to Flutter, you might have encountered situations where different widgets, like text fields and dropdown buttons, need to work together. One common scenario is creating a to-do list app where users can either type in a task or select one from a dropdown menu. This post will guide you through the steps to achieve this functionality in a straightforward manner, ensuring even the newest developers can follow along.

The Problem: How to Connect Dropdown Selections

You're building a screen where users can add tasks for a to-do list. Users have two input options: entering a task through a text field or selecting an option from a dropdown menu. However, you find it challenging to save the selected dropdown value to the same list where you save text field entries. Fear not—there’s a solution to this conundrum!

The Solution: Passing Data Between Widgets

The key to solving this issue lies in passing values between different widgets in Flutter, specifically from the TaskSelect dropdown widget back to the AddTaskScreen widget where you maintain the to-do list.

Step 1: Modify the Dropdown Selector Widget

First, we need to make some changes to the TaskSelect class so it can accept a variable to update with the selected task. Here’s how to do that:

[[See Video to Reveal this Text or Code Snippet]]

In this modification, the TaskSelect widget now takes a Function(String) parameter named onTaskSelected. This function will be called whenever a new task is selected from the dropdown.

Step 2: Update the onChanged Method

Next, we need to adjust the onChanged method in the TaskSelect class to call the onTaskSelected function with the newly selected value. Here’s the updated code:

[[See Video to Reveal this Text or Code Snippet]]

This adjustment ensures that when a user makes a selection in the dropdown, the value is sent back to the parent widget.

Step 3: Update the AddTaskScreen

Now, it’s time to integrate everything back into the AddTaskScreen widget. Modify the code as follows:

[[See Video to Reveal this Text or Code Snippet]]

Now, the AddTaskScreen has a reference to the selected task title through the onTaskSelected callback. It captures the dropdown selection for later use.

Putting It All Together

With these changes, you now have the power to add tasks to your list, whether the user types them in or selects them from a dropdown. Remember to ensure that when the user presses the "Add" button, both entries (from the text field and dropdown) can be added to the to-do list as needed.

Conclusion

Today, we covered how to seamlessly integrate a DropdownButton selection into a Flutter to-do list application. By passing data between your widgets using callbacks, you can easily handle user inputs no matter their source. This pattern is fundamental in Flutter and will serve you well as you continue developing more complex applications. Happy coding!