Im using Angular material's for multipe choice purpose like mentioned in their site https://material.angular.io/components/select/overview (8th example).
I also have an array of items (key and value) which are a part of the choices([key:1 value:extra cheese, key:2 value:onion])... I want them to be automatically selected (probably using formController) ... how can I do this?
plus, after the user selected/ unselectedsome options how do i get a new array back ?
thank you in advance!
you need to use ngModel
<mat-select placeholder="Toppings" [formControl]="toppings"
multiple [(ngModel)]='defaultValue'>
and define this defulatValue in your component like this, or programaticly as you wish
defaultValue = [this.toppingList[1], this.toppingList[3]]
and you can get this variable when anything changes, it will contain your selected values. Took this example from material example, all works fine for me.
Related
I have a datalist that shows the autocompletion of some fields how can I make sure that the input is only a part of that selected field??
You can solve this problem by defining a variable of type number.
After selecting from the input, add a number to the variable and using ngIf in html or if in ts, Control the number of choices.
I assume that you have Street Names in the dropdown and that object also includes street information as well (maybe in some other variable). So you want user to search using the street information as well but in the dropdown you just want to show the user Street names? if that's the case,
you can do something like this:
<datalist>
<option>
{{streetName}} <span style="display:none">{{streetInfo}}</span>
</option>
</datalist>
This way your street information wont be shown but will filter the result on basis of stretInfo as well.
hope it helps.
I am trying to organize a drop down list that will display a single value to the user but will also pass back an array object upon changing the selection.
Currently I have an array called classificationresult that has 3 elements CLASSIFICATION_NAME, GROUP_ID, GROUP_NAME.
When a user selects a particular CLASSIFICATION_NAME I want to pass back the entire array result containing all 3 elements listed above.
Currently the code below works for everything EXCEPT showing the CLASSIFICATION_NAME in the drop-down box upon loading. It shows the list once you click, but it starts with a blank until it is clicked. Any way to fix this? I believe the display element is tied to [ngValue] but that is also what I am using to pass back the entire array versus just the one.
Any help would be greatly appreciated.
<p>Select Classification*</p>
<select [(ngModel)]="selectedClassification (ngModelChange)="changedClassification($event)">
<option *ngFor="let classificationresult of classificationresults" [ngValue]="classificationresult" >{{ classificationresult.CLASSIFICATION_NAME }}</option>
</select>
Summary -- I want my drop down list to always have a value shown to the user (value being the Classification Name) but when one is selected I want the entire array to pass to the changedClassification function. Also sometimes after a user selects from other drops down on this page they will also go blank, but if they are selected a second time they will populate.
If everything is working as you are expecting except the initial value being displayed, I wonder if you need a [compareWith] function. I don't know what your classificationresult model looks like, but if I had to take a guess, putting a [compareWith] function on your <select> element would fix the issue.
Here is an article explaining it a little more.
I made this Stackblitz as an example with using the [compareWith] function. In my demo I am using ReactiveForms, but the compareWith should still be the same.
For your code, it may look something like:
<p>Select Classification*</p>
<!-- add this [compareWith] -->
<select [compareWith]="myCompareFunc" [(ngModel)]="selectedClassification" (ngModelChange)="changedClassification($event)">
<option *ngFor="let classificationresult of classificationresults" [ngValue]="classificationresult" >{{ classificationresult.CLASSIFICATION_NAME }}</option>
</select>
In your .ts file:
export class YourComponent {
// all your component code..
/* compare function, change the logic to fit your needs */
myCompareFunc (classificationRes1: any, classificationRes2: any): boolean {
return classificationRes1 && classificationRes2
? classificationRes1.CLASSIFICATION_NAME === classificationRes2.CLASSIFICATION_NAME
: classificationRes1 === classificationRes2
}
}
If that doesn't fix your issue, you may need to post more of your .ts code and data models.
I'm trying to make a <select> behave with single or multiple selection depending on a condition. So far I have tried:
<select
ng-model="data.model"
ng-attr-multiple="{{myCondition ? '' : undefined}}">
(here's a plnkr I have been testing with https://plnkr.co/edit/ACKBMZSJc2MVSJaDBGMY?p=preview)
But it won't work. Even leaving ng-attr-multiple alone won't work. What am I missing here?
https://docs.angularjs.org/error/$compile/selmulti
Binding to the multiple attribute of select element is not supported
since switching between multiple and single mode changes the ngModel
object type from instance to array of instances which breaks the model
semantics.
If you need to use different types of select elements in your template
based on some variable, please use ngIf or ngSwitch directives to
select one of them to be used at runtime.
I am trying to set the value in an HTML input text box which is a part of ComponentA from the typescript code which is a part of ComponentB.
Taking a clue from this SO i tried doing:
(<HTMLInputElement>document.getElementById("name")).value = response.name;
But this is not working. Is there anything else i need to take care of?
EDIT: The element with Id "name" is in ComponentA and the above code that is trying to manipulate that element is in ComponentB
If you are trying to set the value of component1's textfield from the compoenent2 then you must have to use of ngModel i.e two way data binding. by providing component2 in the providers list you are able to access all the functions and variables of that component, then you can easily set your value. like this
suppose this is your component 2's value property
name:string = 'Pardeep Jain';
than you can access this in component like this-
<input type="text" [(ngModel)]='name'>
....
constructor(private delete1: Delete){
this.name = this.delete1.name;
}
Working Example
Also
(<HTMLInputElement>document.getElementById("name")).value = response.name;
is used to set the value of current template's field with id named as **name**
This is one of the cases when user interaction on one component ComponentA triggers an update on another component ComponentB.
This article describes multiple approaches, with example code, on how to pass information between components.
My personal favorite is the third approach mentioned in that article in which one of the component (say ComponentA) "listen" for update it is concerned about from any component (say ComponentB) via a service in between them, resulting in a loosely coupled components.
For more approaches here is another link.
I am completely stumped on this one. Everything's working fine (or fine enough for now) and all I need is to get the data back out of the factory in a non-json format. I've got a semi-working plunker with all the details.
Basically, the first page (under the Ctrl controller) is where a user can check a bunch of boxes. There's also an ng-switch between sets of options (the real things are much, much larger lists than these), so the checkboxFactory maintains the user's choices. When the user goes to the next page (or "next page" in the plunker because faking it), they can see what they chose. Those choices will then get wrapped up in a json post back to the server. I need to show the user-friendly name, but also have the id# of the choice, for the server.
If I put value="{{item.name}}" in the original checkbox ng-repeat, everything is fine. Except for the fact that then I have a factory of names, and not the server-required ids. Doing a second array in the factory (one for selected names, one for the corresponding selected ids) seems like overkill, when theoretically I could just add each selection as an object, and extract the properties as needed on the second page.
In reality, it's not working. Here's what I get if I echo the factory, after selections are made:
[ "{\"id\":1,\"name\":\"Firstplace\"}", "{\"id\":2,\"name\":\"Second place\"}" ]
...and I'm not sure, but those backslashes seem to be turning every selection into strings, because there are quotes just inside the square brackets. I've tried editing line 54 in the script, but I get errors. It doesn't like this:
if (checked && index == -1) {
if (setup) elem.prop('checked', false);
else scope.list.push({
id:"scope.value.id",
name:"scope.value.name"
});
On the html side, it doesn't like any of the variations I've tried in the ng-repeat, either. It seems like the source of all nightmares is that pushing is creating deformed json. I've tried all of these the second page/output:
{{item}}
{{item.name}}
{{item.item.name}}
The only one that works is {{item}} and unsurprisingly it's pretty ugly. Has anyone run into this before, and have any hints on how to fix this? Many thanks in advance.
using # will turn your object into a string, you should just use a reference to your item object instead and use =.
Change {{item}} to just item as a reference:
<input type="checkbox" name="group1" value="item" ng-model="isChecked" checkbox-list='checkedCity' />
In directive use =:
scope: {
list: '=checkboxList',
value: '='
},
see updated plunker