dropdownbutton

How to resolve flutter dropdownButtonFormField dynamic selection checking for dropdownButton's value

由 旧时模样 提交于 2021-01-07 02:43:47
问题 I am trying to ask the user to select the type of item in the first dropdown and then select from its corresponding available colours in the second dropdown. However, when after I have selected a colour (i.e. white) and now want to switch to another item that does not have this colour, an error is thrown: "There should be exactly one item with [DropdownButton]'s value: white. \nEither zero or 2 or more [DropdownMenuItem]s were detected with the same value" Please help, I have already tried to

Flutter DropDownButton Popup 200px below Button

由 早过忘川 提交于 2021-01-04 09:22:12
问题 I'm using a DropDownButton with a custom style inside a ListView. My problem is: the PopupMenu opens about 200-300px below the Button so it looks like the Button below that has opened: I wrapped the Dropdown in a custom style, but i already tried removing that and that did nothing. I've also tried to use just a normal Dropdownbutton, but that had the same effect. the corresponding build: @override Widget build(BuildContext context) { homeModel = Provider.of<HomeModel>(context); model =

Flutter DropDownButton Popup 200px below Button

由 雨燕双飞 提交于 2021-01-04 09:22:06
问题 I'm using a DropDownButton with a custom style inside a ListView. My problem is: the PopupMenu opens about 200-300px below the Button so it looks like the Button below that has opened: I wrapped the Dropdown in a custom style, but i already tried removing that and that did nothing. I've also tried to use just a normal Dropdownbutton, but that had the same effect. the corresponding build: @override Widget build(BuildContext context) { homeModel = Provider.of<HomeModel>(context); model =

Flutter - Dependent/Multilevel DropdownButton has an issue: There should be exactly one item with [DropdownButton]'s value: Ointments

由 空扰寡人 提交于 2020-05-31 04:41:05
问题 If someone can please help me with this issue. So I am able to fetch and insert into the dropdownbuttons using the code below. If i select the first dropdown then the list shows accordingly for the second dropdown and if i pick another value the list changes. But when I select between the lists more than once it gives me an error for example: Another exception was thrown: There should be exactly one item with [DropdownButton]'s value: Ointments. Either zero or 2 or more [DropdownButton]'s

Set default value for dropdown button in flutter

由 白昼怎懂夜的黑 提交于 2019-12-11 18:04:37
问题 I have a dropdown button which works fine, but when I try to set a default value it will fail with the following error: 'package:flutter/src/material/dropdown.dart': Failed assertion: line 620 pos 15: 'items == null || items.isEmpty || value == null || items.where((DropdownMenuItem item) => item.value == value).length == 1': is not true. This is my dropdown button: Widget changeWorkspace() { return StatefulBuilder( builder: (BuildContext context, StateSetter setState) { return Column

How to make flutter custom drop down button?

由 試著忘記壹切 提交于 2019-12-06 12:43:35
问题 I want to Customise DropDownButton, so that it does not render the content of DropdownItem. Instead it should render my Custom layout/widget before and after selecting an item from DropDown. In simple Words, I want to customise my DropDownButton. Thanks, 回答1: How to render DropdownButton items differently when it is dropped down? I found a solution through DropdownMenuItem . Its build() is executed separately for closed and dropped down state. You can use the context to find out if it is

How to make flutter custom drop down button?

由 ≯℡__Kan透↙ 提交于 2019-12-04 15:01:00
I want to Customise DropDownButton , so that it does not render the content of DropdownItem . Instead it should render my Custom layout/widget before and after selecting an item from DropDown. In simple Words, I want to customise my DropDownButton . Thanks, bdi How to render DropdownButton items differently when it is dropped down? I found a solution through DropdownMenuItem . Its build() is executed separately for closed and dropped down state. You can use the context to find out if it is closed or dropped down state. e.g you can check for an ancestor stateful widget. I use something like

Disable elements when Shiny is busy

由 此生再无相见时 提交于 2019-12-04 06:25:19
问题 I'm using a piece of javascript from this question: SO It works for buttons, but I would also like to disable things like sliderInput , selectInput and textInput as well. I tried to replace the 'button' with 'input' which does disable the textinput fields. I am wondering whether there is a way to disable all elements in 1 go. The bigger problem is the following: When you open the dropdownbutton , the close button normally should remove the modal dialog in case the javascript tag is removed
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