So I have a list of schedules that I need to display for a user and show which schedules he or she is currently on and give them the possibility to jump on and off said schedules.
My viewmodel looks like this
self = this;
self.shifts = ko.observableArray();
self.selectedShifts = ko.observableArray();
//I populate self.shifts here with a WEB API call
//Run through each shift and check if current user is on it and set checked / not checked value for checkbox
ko.utils.arrayForEach(self.shifts(), function(shift) {
//Clear array
self.usersOnShift([]);
//Populate array with all users on the shift
self.usersOnShift = ko.observableArray(WEB API CALL HERE);
var userInShift = ko.utils.arrayFirst(self.usersOnShift(), function(user) {
if (selectedUserId == user.ID) {
return true;
}
});
if (userInShift) {
self.selectedShifts.push(shift.ID);
}
});
ko.applyBindings(self);
My HTML looks like this
<div class="simple_overlay" id="shiftOverlay">
<div class="details">
<div data-bind="foreach: shifts">
<div><span class="staff-initials" data-bind="text:wardName"> </span><input type="checkbox" data-bind="value: ID, checked: $root.selectedShifts"/> </div>
</div>
<div>
<a href="#" data-bind="click: updateUserOnShifts">Connect</a>
<a href="#" data-bind="click: closeShiftDialog">Close</a>
</div>
</div>
</div>
I can see that the value of the checkboxes are set correctly to the ID of the corresponding shifts. However a shift that I know the user in question is on is not checked and I know that the selectedShifts observableArray contains the value.
Somehow the "checked: $root.selectedShifts" call / check is not working but I know that it contains the right value. What am I doing wrong?
So I have a list of schedules that I need to display for a user and show which schedules he or she is currently on and give them the possibility to jump on and off said schedules.
My viewmodel looks like this
self = this;
self.shifts = ko.observableArray();
self.selectedShifts = ko.observableArray();
//I populate self.shifts here with a WEB API call
//Run through each shift and check if current user is on it and set checked / not checked value for checkbox
ko.utils.arrayForEach(self.shifts(), function(shift) {
//Clear array
self.usersOnShift([]);
//Populate array with all users on the shift
self.usersOnShift = ko.observableArray(WEB API CALL HERE);
var userInShift = ko.utils.arrayFirst(self.usersOnShift(), function(user) {
if (selectedUserId == user.ID) {
return true;
}
});
if (userInShift) {
self.selectedShifts.push(shift.ID);
}
});
ko.applyBindings(self);
My HTML looks like this
<div class="simple_overlay" id="shiftOverlay">
<div class="details">
<div data-bind="foreach: shifts">
<div><span class="staff-initials" data-bind="text:wardName"> </span><input type="checkbox" data-bind="value: ID, checked: $root.selectedShifts"/> </div>
</div>
<div>
<a href="#" data-bind="click: updateUserOnShifts">Connect</a>
<a href="#" data-bind="click: closeShiftDialog">Close</a>
</div>
</div>
</div>
I can see that the value of the checkboxes are set correctly to the ID of the corresponding shifts. However a shift that I know the user in question is on is not checked and I know that the selectedShifts observableArray contains the value.
Somehow the "checked: $root.selectedShifts" call / check is not working but I know that it contains the right value. What am I doing wrong?
Share Improve this question edited Mar 17, 2014 at 12:17 thomasvdb 7491 gold badge12 silver badges32 bronze badges asked Mar 21, 2013 at 22:32 MemphisMemphis 2711 gold badge6 silver badges16 bronze badges 3-
Is
shift.ID
a string or a number? – Michael Best Commented Mar 21, 2013 at 23:06 -
It seems strange that
usersOnShift
is an observable and that it's part of the view-model since it's just needed within the loop. – Michael Best Commented Mar 21, 2013 at 23:10 - shift.ID is an integer. True that usersOnShift needed not be part of the viewModel. Couldn't issue be in the HTML where I reference the selectedShifts with the $root context? – Memphis Commented Mar 21, 2013 at 23:32
2 Answers
Reset to default 10The problem is that your value is an integer, but when bound to the checkbox
element, it bees a string. When the checked
binding tries to find the value in the array, it doesn't find a match because it uses strict equality for parison and (2 === "2")
is false.
The simplest way to work around this problem is to convert your values to string when you add them to the array:
self.selectedShifts.push("" + shift.ID);
Of course this means that your model has to change, and that might not be a great solution. I came up with a custom binding, checkedInArray
that replaces checked
and supports any type of value. You can learn about it, see it in action, and use it like this:
<input type="checkbox" data-bind="checkedInArray: {value: ID, array: $root.selectedShifts }" />
In Knockout 2.3.0 (which is still in development) there will be a new binding, checkedValue
, that will allow you use any type of value with the checked
binding. Using that version, you could update your HTML to use checkedValue
:
<input type="checkbox" data-bind="checkedValue: ID, checked: $root.selectedShifts"/>
Is shift.ID an observable property? If it is, then you need to add it to the array like this:
self.selectedShifts.push(shift.ID());
Otherwise you're just adding the whole observable to the array, and not the value.