I have two check boxes and they are populating when the user is selected, but I now need to check the values and return them before saving them back to database in case they have been changed, below is my plunker with my working code if you select a tradesman from the drop down the ticket boxes are populated.
If someone could advise how I can get check the tick box values that would be great, this is what I have tried but I am missing something:
<input type="input" name="adminis" id="adminis" class="form-control" [(ngModel)]="tradesman.user_roles"/>
Plunker demo
To find whether a checkbox value is changed or not, you can use (change) attribute.
<input type="checkbox" [checked]="tradesman?.user_roles?.includes('Administrator') ? true : false" value="Administrator" (change)="valueChanged($event)"/>Admin
<input type="checkbox" [checked]="tradesman?.user_roles?.includes('General User') ? true : false" value="General User" (change)="valueChanged($event)" />General
In your component, you can manage the data using the event passed.
valueChanged(e:any){
/* e.target.name - for getting the changed field name */
/* e.target.checked - for getting the value - true(checked)/false(unchecked) */
}
Then you can update your array or whatever with this new value.
Related
(I'm new to Svelte so it is quite likely that I'm doing something wrong here)
UPDATE: I've added a second, slightly different REPL which may demonstrate the problem better. Try this one: https://svelte.dev/repl/ad7a65894f8440ad9081102946472544?version=3.20.1
I've encountered a problem attempting to bind a text input to a reactive value.
I'm struggling to describe the problem in words, so hopefully a reduced demo of the issue in the attached REPL will make more sense.
https://svelte.dev/repl/6c8068ed4cc048919f71d87f9d020696?version=3.20.1
The demo contains two custom <Selector> components on a page.
The first component is passed two string values ("one" and "two"):
<Selector valueOne="one" valueTwo="two"/>
Clicking the buttons next to the input field sets selectedValue to one of these values.
This, in turn, triggers the following reactive declaration to update:
$: value = selectedValue
The input field is bound to this reactive value:
<input type="text" bind:value>
So clicking the "One" button sets the input text to "one", and clicking the "Two" button sets the input field to "two".
Importantly though, you can still type anything into the input field.
The second component is passed two array values:
<Selector valueOne={[1, "one"]} valueTwo={[2, "two"]}/>
Again, clicking the buttons sets selectedValue to one of these.
However this time the reactive declaration depends on an array element:
$: value = selectedValue[1]
Everything works as before, except now you can no longer type into the input field at all.
So the question is - why does <input bind:value> behave differently for these two:
$: value = aString
vs
$: value = anArray[x]
It seems that this is only an issue when using two-way bindings.
By switching to a one-way and an on:input handler, the problem goes away:
i.e. instead of this:
<input type="text" bind:value={valX}/>
use this:
<input type="text" value={valX} on:input={e => valX = e.target.value}/>
I'm pretty sure your reactive declaration is overwriting your bound value as soon as it changes, which is with every key stroke on the input and every button press. Meaning it technically is working, you're just reverting it each time it changes. Check out this version of it that uses a watcher.
Also binding to a reactive declaration means you're never actually changing the variables with the input (which you can see in your JSON result on the first selector when you type in the input the value doesn't update only on button click).
Why not lose the reactive declaration and bind directly to the variable you want. Then use an {#if} block to switch between which version of the input you're showing based on the truthiness of index?
<script>
export let valueOne;
export let valueTwo;
export let index;
let selectedValue = index? [] : '';
let selectValue = (val) => selectedValue = val;
</script>
{#if index}
<input type="text" bind:value={selectedValue[index]} placeholder="Type anything...">
{:else}
<input type="text" bind:value={selectedValue} placeholder="Type anything...">
{/if}
<button on:click={() => selectValue(valueOne)}>One</button>
<button on:click={() => selectValue(valueTwo)}>Two</button>
<p>
<strong>Selected value:</strong> {JSON.stringify(selectedValue)}
</p>
By binding directly to the selectedValue or an index of it you have the added benefit of changing the value with the input. Here's a working example in the REPL
I have used the uib-typeahead directive as follows :
<input type="text" id="search-box" class="form-control" data-ng-model="searchBar.search.searchString"
typeahead-on-select="searchBar.gotoPartDetails($item, $model, $label, $event)" uib-typeahead="result as result.partNumber+' '+result.lineDesc+' '+result.partDesc for result in searchBar.textTyped($viewValue)"
placeholder="Search by part number, product type, product line, keyword" typeahead-focus-first="searchBar.search.firstSelect" typeahead-popup-template-url="app/components/header/search-bar/typeahead-popup.html" typeahead-template-url="{{searchBar.search.typeaheadTemplate}}"
data-ng-focus="searchBar.focus()" data-ng-blur="searchBar.blur()">
I am basically using the "searchBar.search.firstSelect" scope variable to enable or disable first select. On controller load searchBar.search.firstSelect is set to false and based on the size of the length data displayed. If the typeahead is showing just one data in the options I am setting searchBar.search.firstSelect to true. But this is not reflecting in the UI. What do I do?
i want to create a input textbox with value link and write a code like this:
<form>
<input name="Textboxfield" type="text" value=".jpg"><br>
<input name="Launchlink" type="button" value="Launch link" onclick="location.href=this.form.elements['Textboxfield'].value">
</form>
this is a good code for me but have some problems.
in this code the value ".jpg" is variable but i wants to keep it stable who when user insert his/her number in textbox, can go to destination link.
for example:
i insert my number 22456 in this textbox like this: 22456.jpg
and when i press botton the page directly go to my file (a pic).
but
when i insert my number without .jpg format the page goes wrong and break the system (show index page)
and thats my problem! how can i have stable value link ".JPG" who when user jus isert his/her number to textbox the page directlty go to his/her file and show it.
also you can see this image:
http://0o.8415.2.img98.com/out.php/i543815_code.jpg
please help me guys...
Try this
<form><input name="Textboxfield" type="text" value=".jpg"><br>
<input name="Launchlink" type="button" value="Launch link" onclick="location.href=this.form.elements['Textboxfield'].value + '.jpg'">
</form>
You could check if the textbox value ends with ".jpg" using Javascript, and if it doesn't, append ".jpg" to whatever value is in the textbox. You could add this function to the onClick() handler of your button or somewhere.
You could write the function checkJPG() as:
<script type="text/javascript">
function checkJPG() {
var myText = document.getElementByID("myTextBoxID").value;
if (myText.substr(-1, 4) == ".jpg")
//do nothing
else
//append .jpg to the value in the textbox
}
</script>
I'm just now starting to learn ASP.NET MVC. How would I go about creating a reusable tri-state checbox? In WebForms this would be a control, but I don't know the MVC equivalent.
Add a TriStateCheckBox (or TriStateCheckBoxFor if you use the strongly typed overloads) extension method to HtmlHelper and add the namespace of that extension method class to the namespaces section of your web.config.
As for the implementation, I'd recommend having at look at the InputExtensions source on codeplex and using that to create your own.
Limitations:
View Rendering - When rendering HTML content, there is no attribute you can possibly place on an <input type="checkbox" /> that will give it the property indeterminate.
At some point, you'll have to use JavaScript to grab the element and set the indeterminate property:
// vanilla js
document.getElementById("myChk").indeterminate = true;
// jQuery
$("#myCheck).prop("indeterminate", true);
Form Data - model binding will always be limited to what values are actually sent in the request, either from the url or the data payload (on a POST).
In this simplified example, both unchecked and indeterminate checkboxes are treated identically:
And you can confirm that for yourself in this Stack Snippet:
label {
display: block;
margin-bottom: 3px;
}
<form action="#" method="post">
<label >
<input type="checkbox" name="chkEmpty">
Checkbox
</label>
<label >
<input type="checkbox" name="chkChecked" checked>
Checkbox with Checked
</label>
<label >
<input type="checkbox" name="chkIndeterminate" id="chkIndeterminate">
<script> document.getElementById("chkIndeterminate").indeterminate = true; </script>
Checkbox with Indeterminate
</label>
<label >
<input name="RegularBool" type="checkbox" value="true">
<input name="RegularBool" type="hidden" value="false">
RegularBool
</label>
<input type="submit" value="submit"/>
</form>
Model Binding - Further, model binding will only occur on properties that are actually sent. This actually poses a problem even for regular checkboxes, since they won't post a value when unchecked. Value types do always have a default value, however, if that's the only property in your model, MVC won't new up an entire class if it doesn't see any properties.
ASP.NET solves this problem by emitting two inputs per checkbox:
Note: The hidden input guarantees that a 'false' value will be sent even when the checkbox is not checked. When the checkbox is checked, HTTP is allowed to submit multiple values with the same name, but ASP.NET MVC will only take the first instance, so it will return true like we'd expect.
Render Only Solution
We can render a checkbox for a nullable boolean, however this really only works to guarantee a bool by converting null → false when rendering. It is still difficult to share the indeterminate state across server and client. If you don't need to ever post back indeterminate, this is probably the cleanest / easiest implementation.
Roundtrip Solution
As there are serious limitations to using a HTML checkbox to capture and post all 3 visible states, let's separate out the view of the control (checkbox) with the tri-state values that we want to persist, and then keep them synchronized via JavsScript. Since we already need JS anyway, this isn't really increasing our dependency chain.
Start with an Enum that will hold our value:
/// <summary> Specifies the state of a control, such as a check box, that can be checked, unchecked, or set to an indeterminate state.</summary>
/// <remarks> Adapted from System.Windows.Forms.CheckState, but duplicated to remove dependency on Forms.dll</remarks>
public enum CheckState
{
Checked,
Indeterminate,
Unchecked
}
Then add the following property to your Model instead of a boolean:
public CheckState OpenTasks { get; set; }
Then create an EditorTemplate for the property that will render the actual property we want to persist inside of a hidden input PLUS a checkbox control that we'll use to update that property
Views/Shared/EditorTemplates/CheckState.cshtml:
#model CheckState
#Html.HiddenFor(model => model, new { #class = "tri-state-hidden" })
#Html.CheckBox(name: "",
isChecked: (Model == CheckState.Checked),
htmlAttributes: new { #class = "tri-state-box" })
Note: We're using the same hack as ASP.NET MVC to submit two fields with the same name, and placing the HiddenFor value that we want to persist first so it wins. This just makes it easy to traverse the DOM and find the corresponding value, but you could use different names to prevent any possible overlap.
Then, in your view, you can render both the property + checkbox using the editor template the same way you would have used a checkbox, since it renders both. So just add this to your view:
#Html.EditorFor(model => model.OpenTasks)
The finally piece is to keep them synchronized via JavaScript on load and whenever the checkbox changes like this:
// on load, set indeterminate
$(".tri-state-hidden").each(function() {
var isIndeterminate = this.value === "#CheckState.Indeterminate";
if (isIndeterminate) {
var $box = $(".tri-state-box[name='" + this.name + "'][type='checkbox']");
$box.prop("indeterminate", true);
}
});
// on change, keep synchronized
$(".tri-state-box").change(function () {
var newValue = this.indeterminate ? "#CheckState.Indeterminate"
: this.checked ? "#CheckState.Checked"
: "#CheckState.Unchecked";
var $hidden = $(".tri-state-hidden[name='" + this.name + "'][type='hidden']");
$hidden.val(newValue);
});
Then you can use however you'd like in your business model. For example, if you wanted to map to a nullable boolean, you could use the CheckState property as a backing value and expose/modify via getters/setters in a bool? like this:
public bool? OpenTasksBool
{
get
{
if (OpenTasks == CheckState.Indeterminate) return null;
return OpenTasks == CheckState.Checked;
}
set
{
switch (value)
{
case null: OpenTasks = CheckState.Indeterminate; break;
case true: OpenTasks = CheckState.Checked; break;
case false: OpenTasks = CheckState.Unchecked; break;
}
}
}
Alternative Solution
Also, depending on your domain model, you could just use Yes, No, ⁿ/ₐ radio buttons
ASP.NET MVC certainly doesn't provide such component, actually it simply relies on the standard elements available in HTML but you may want to check out this solution.
I am developing a Grails (1.0.4) app where I want to edit a collection of collections on a single page in a grid view. I got it to work quite well depending only on the indexed parameter handling of Spring MVC, except for one thing:
boolean (or, for that matter, Boolean) values in the grid can be set via checkbox, but not unset, i.e. when I check the checkbox and update, the value is set to true, but afterwards when I edit again, uncheck the checkbox and update, it remains true.
This is the GSP code of the checkbox:
<g:checkBox name="tage[${indexTag}].zuweisungen[${indexMitarb}].fixiert" value="${z.fixiert}" />
And this is the HTML that is generated:
<input type="hidden" name="tage[0].zuweisungen[0]._fixiert" />
<input type="checkbox" name="tage[0].zuweisungen[0].fixiert" checked="checked" id="tage[0].zuweisungen[0].fixiert" />
I've found a Grails bug that describes exactly this effect, but it's marked as fixed in 1.0.2, and the problem mechanism described there (underscore in hidden field name is put in the wrong place) is not present in my case.
Any ideas what could be the reason?
This is the solution a guy named Julius Huang proposed on the grails-user mailing list. It's reusable but relies on JavaScript to populate a hidden field with the "false" response for an unchecked checkbox that HTML unfortunately does not send.
I hack GSP to send "false" when
uncheck the box (true -> false) with
custom TagLib.
By default checkBox send nothing when
uncheck, so I use the checkBox as
event handler but send hidden field
instead.
"params" in Controller can handle
"false" -> "true" without any
modification. eg. Everything remain
same in Controller.
The Custom Tag Usage in GSP (sample usedfunc_F is "true"),
<jh:checkBox name="surveyList[${i}].usedfunc_F" value="${survey.usedfunc_F}"></jh:checkBox>
Here is what the Tag generate,
<input type="hidden" name="surveyList[#{i}].usedfunc_F" id="surveyList[#{i}].usedfunc_F" value="false" />
<input type="checkbox" onclick="jhtoggle('surveyList[#{i}].usedfunc_F')" checked="checked" />
The Javascript
<script type="text/javascript">
function jhtoggle(obj) {
var jht = document.getElementById(obj);
jht.value = (jht.value !='true' ? 'true' : 'false');
}
</script>
This is my own solution, basically a workaround that manually does what the grails data binding should be doing (but doesn't):
Map<String,String> checkboxes = params.findAll{def i = it.key.endsWith("._fixiert")} // all checkboxes
checkboxes.each{
String key = it.key.substring(0, it.key.indexOf("._fixiert"))
int tagIdx = Integer.parseInt(key.substring(key.indexOf('[')+1, key.indexOf(']')))
int zuwIdx = Integer.parseInt(key.substring(key.lastIndexOf('[')+1, key.lastIndexOf(']')))
if(params.get(key+".fixiert"))
{
dienstplanInstance.tage[tagIdx].zuweisungen[zuwIdx].fixiert = true
}
else
{
dienstplanInstance.tage[tagIdx].zuweisungen[zuwIdx].fixiert = false
}
}
Works, requires no change in grails itself, but isn't reusable (probably could be made so with some extra work).
I think that the simplest workaround would be to attach a debugger and see why Grails is failing to populate the value. Considering Grails is open source you'll be able to access the source code and once you figure out the solution for it you can patch your version.
I have also found this other bug GRAILS-2861 which mentions the issue related to binding to booleans (see Marc's comment in the thread). I guess that is exactly the problem you are describing.
I would create a small sample app that demonstrates the problem and attach it to the Grails bug (or create a new one). Someone here may be able to debug your sample app or you'll have shown the bug isn't really fixed.
Try this out, set the logs to DEBUG, frist try the first 3 if they don't show the problem up, flip them all to DEBUG:
codehaus.groovy.grails.web.servlet="error" // controllers
codehaus.groovy.grails.web.pages="error" // GSP
codehaus.groovy.grails.web.sitemesh="error" // layouts
codehaus.groovy.grails."web.mapping.filter"="error" // URL mapping
codehaus.groovy.grails."web.mapping"="error" // URL mapping
codehaus.groovy.grails.commons="info" // core / classloading
codehaus.groovy.grails.plugins="error" // plugins
codehaus.groovy.grails.orm.hibernate="error" // hibernate integration
This should allow you to see exactly when and how the parameters setting is failing and probably figure out a work around.