What is the easiest way to combine ng-changed and ng-blur?
I've found this post: How to let ng-model not update immediately?
However, this does no longer work in angluar 1.2+ Is there any way to achieve the same behavior?
I guess I have to store a copy of the old value myself and compare the new value to that on blur if I try to do the same, or is there any easier way ?
Use ng-model options.
Like this, ng-change will only trigger when the input is blurred.
<input type="text"
ng-model="a.b"
ng-model-options="{updateOn: 'blur'}"
ng-change="onchange()"/>
This does what I want. It stores the value on focus, and compares it to the new value on blur, if changed, it triggers the expression in the attribute.
app.directive('changeOnBlur', function() {
return {
restrict: 'A',
require: 'ngModel',
link: function(scope, elm, attrs, ngModelCtrl) {
if (attrs.type === 'radio' || attrs.type === 'checkbox')
return;
var expressionToCall = attrs.changeOnBlur;
var oldValue = null;
elm.bind('focus',function() {
scope.$apply(function() {
oldValue = elm.val();
console.log(oldValue);
});
})
elm.bind('blur', function() {
scope.$apply(function() {
var newValue = elm.val();
console.log(newValue);
if (newValue !== oldValue){
scope.$eval(expressionToCall);
}
//alert('changed ' + oldValue);
});
});
}
};
});
usage:
<input ng-model="foo" change-on-blur="someFunc()" />
How about this solution. Works for me:
<input ng-init="oldValue = value" ng-model="value"
ng-blur="oldValue != value && callYourFunc(foo)">
I am using AngularJs 1.2.x and stumbled upon the ng-change issue of firing on each change. ng-blur can be used but it fires even though there is no change in the value. So both cannot be used efficiently.
With Angularjs 1.3.x, things are easier using ng-model-options like below
to invoke change function "onBlur"
ng-change="ctrl.onchange()" ng-model-options="{updateOn: 'blur'}"
And
to delay invocation of change function by 500ms
ng-change="ctrl.onchange()" ng-model-options='{ debounce: 500 }'"
Now coming to back to the question of getting such things with AngularJs 1.2.x
to invoke change function "onBlur"
html
<input type="text" ng-model="ctrl.a.c" sd-change-on-blur="ctrl.onchange()" />
or
<input type="text" ng-model="ctrl.a.c" sd-change-on-blur="ctrl.onchange(ctrl.a.c)" />
JS
app.directive('sdChangeOnBlur', function() {
return {
restrict: 'A',
scope: {
sdChangeOnBlur: '&'
},
link: function(scope, elm, attrs) {
if (attrs.type === 'radio' || attrs.type === 'checkbox')
return;
var parameters = getParameters(attrs.sdChangeOnBlur);
var oldValue = null;
elm.bind('focus', function() {
scope.$apply(function() {
oldValue = elm.val();
});
})
elm.bind('blur', function() {
scope.$apply(function() {
if (elm.val() != oldValue) {
var params = {};
if (parameters && parameters.length > 0) {
for (var n = 0; n < parameters.length; n++) {
params[parameters[n]] = scope.$parent.$eval(parameters[n]);
}
} else {
params = null;
}
if (params == null) {
scope.sdChangeOnBlur();
} else {
scope.sdChangeOnBlur(params)
}
}
});
});
}
};
});
function getParameters(functionStr) {
var paramStr = functionStr.slice(functionStr.indexOf('(') + 1, functionStr.indexOf(')'));
var params;
if (paramStr) {
params = paramStr.split(",");
}
var paramsT = [];
for (var n = 0; params && n < params.length; n++) {
paramsT.push(params[n].trim());
}
return paramsT;
}
to delay invocation of change function by 500ms
html
<input type="text" ng-model="name" sd-change="onChange(name)" sd-change-delay="300"/>
OR
<input type="text" ng-model="name" sd-change="onChange()" sd-change-delay="300"/>
JS
app.directive('sdChange', ['$timeout',
function($timeout) {
return {
restrict: 'A',
scope: {
sdChange: '&',
sdChangeDelay: '@' //optional
},
link: function(scope, elm, attr) {
if (attr.type === 'radio' || attr.type === 'checkbox') {
return;
}
if (!scope.sdChangeDelay) {
scope.sdChangeDelay = 500; //defauld delay
}
var parameters = getParameters(attr.sdChange);
var delayTimer;
elm.bind('keydown keypress', function() {
if (delayTimer !== null) {
$timeout.cancel(delayTimer);
}
delayTimer = $timeout(function() {
var params = {};
if (parameters && parameters.length > 0) {
for (var n = 0; n < parameters.length; n++) {
params[parameters[n]] = scope.$parent.$eval(parameters[n]);
}
} else {
params = null;
}
if (params == null) {
scope.sdChange();
} else {
scope.sdChange(params)
}
delayTimer = null;
}, scope.sdChangeDelay);
scope.$on(
"$destroy",
function(event) {
$timeout.cancel(delayTimer);
console.log("Destroyed");
}
);
});
}
};
}
]);
function getParameters(functionStr) {
var paramStr = functionStr.slice(functionStr.indexOf('(') + 1, functionStr.indexOf(')'));
var params;
if (paramStr) {
params = paramStr.split(",");
}
var paramsT = [];
for (var n = 0; params && n < params.length; n++) {
paramsT.push(params[n].trim());
}
return paramsT;
}
plnkrs for both approaches are
how about this plunkr?
using angular's built in ng-blur, update your "persisted value" on blur
<input type="text" ng-model="boxValue" ng-blur="doneEditing(boxValue)">
when saving, verify the value is different
$scope.doneEditing = function(v) {
if (v !== $scope.persistedValue) // only save when value is different
$scope.persistedValue=v;
}
There is no special option on ng-blur for pre-checking equality that I'm aware of. A simple if seems to do the trick
The solution that worked for me was as follows:
<input id="fieldId" type="text"
ng-model="form.fields.thisField"
ng-model-options="{ updateOn: 'blur' }"
ng-change="form.save()" />
I found this solution here
That page says it requires AngularJS version 1.3.0+ . I tested it with AngularJS version 1.5.11 and it works in that version for me.
In app.html
<input type="text" name="name" ng-model="$ctrl.user.name" ng-blur="$ctrl.saveChanges()" ng-change="$ctrl.onFieldChange()"/>
in app.ts
public onFieldChange() {
this.isValuesModified = true;
}
//save changes on blur event
public saveChanges() {
//check if value is modified
if(this.isValuesModified){
//Do your stuff here
}
}
This is how I resolved this.
<input ng-focus="oldValue=value" ng-model="value" ng-blur="oldValue!=value && youFunction()" />
