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Questions - flutter-dropdownbutton

Failed assertion: line 1252 pos 12: 'widget.items!.where((DropdownMenuItem<T> item) => item.value == widget.value).length == 1': is not true

I am getting this error in the console when I am trying to use flutter DropdownButton Widget. package:flutter/src/material/dropdown.dart': Failed assertion: line 1252 pos 12: 'widget.items!.where((Dr...
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Harshit

flutter

dropdown

flutter-widget

flutter-dropdownbutton

Votes: 0

Answers: 3

Latest Answer

You are missing value on DropdownMenuItem. .map((_value) => DropdownMenuItem<String>( value: _value, // this child: Text( _value, ))) Also make sure to use...
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Md. Yeasin Sheikh

In Flutter, I am making a bible app using a json file of the format shown bellow... I want you to help me with the Drop Down selection

I want a dependent dropdown selection for The Book Name (Independent) The Chapter (Dependent) The Verse (Dependent) I Want the Dropdown to be in this format First, Independent Dropdown Select using ...
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Joel Lee

flutter

flutter-listview

flutter-dropdownbutton

Votes: 0

Answers: 1

Latest Answer

Here is what you can do, make a list of chapters as a seperate json file and connect the first dropdown to that list then for the second list should show the number of chapters of the first book json[...
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Raghu Iyer

In Flutter, I am trying to make a dependent dropdown with the following json

In Flutter, I am trying to make a dependent dropdown with the following json. I Want the Dropdown to be in this format First, Independent Dropdown dataNames Second, Dependent Dropdown indexes of the d...
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Joel Lee

flutter

flutter-dropdownbutton

flutter-future

Votes: 0

Answers: 1

Latest Answer

Here is the first step: parsing the json into a class model and then creating a list of models. second step build the DropdownMenuItem list to be consumed by the DropDownbutton. Create a _currentRe...
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Golden Lion

Populate DropdownButton with sqflite in Flutter, when selecting value(OnChange) returns error

_AssertionError ('package:flutter/src/material/dropdown.dart': Failed assertion: line 894 pos 15: 'items == null || items.isEmpty || value == null || items.where((DropdownMenuItem<T> item) { r...
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alyson pereira

flutter

dart

flutter-dropdownbutton

Votes: 0

Answers: 1

Latest Answer

Try this: FutureBuilder( future: Future.delayed(Duration(seconds: 1)) .then((value) => _daoCateg.findAll_categoria()), builder: (context, AsyncSnapshot...
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Josteve

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