As the title says. I want to be able to reload a layer that is displayed on the map. Is there a way to do this (directly)?
So not map.render() or map.renderSync(), because these renders only change the view after scrolling or changing the view.
To reload a geojson vector layer you have to clear it first and then do the same as you did in first place: loading de layer and setting the layer source:
vectorLayerSource.clear();
loadVectorLayer(url);
The steps for loading the geojson layer depends on your configuration, assuming that you have it in an external geojson file you could do it like that (using jquery):
function loadVectorLayer(url) {
$.when(
$.getJSON(url, {})
.done (function(data) {
var features = (new ol.format.GeoJSON()).readFeatures(data);
vectorLayerSource.addFeatures(features);
})
.fail(function(data) {
console.log("geojson error in "+url);
})
).then(function() {
console.log("geojson file "+url+" loaded");
});
}
Related
I have this code https://jsfiddle.net/delux123/62Lmskbx/11/ where user can draw circle, segment and arrow-segment. When each annotation is selected, there is a "delete" button available, which should normally delete the selected annotation.
But this does not works! I tried the following ways for removing them:
1 ) using thischart.currentAnnotation.destroy() will delete the annotation (works for all three types) but then all the further actions stops from working
document
.querySelectorAll('.highcharts-popup-annotations .deletebutton')[0]
.addEventListener(
'click',
function() {
thischart.currentAnnotation.destroy(); //this stops further drawing
thischart.annotationsPopupContainer.style.display = 'none';
}
);
2 ) using deletion by ID thischart.removeAnnotation(thischart.currentAnnotation.options.id) does not works, since the annotations are created dynamically and they do not have IDs assigned to them.
document
.querySelectorAll('.highcharts-popup-annotations .deletebutton')[0]
.addEventListener(
'click',
thischart.removeAnnotation(thischart.currentAnnotation.options.id); //this requires elements to have IDs (which they do not have)
thischart.annotationsPopupContainer.style.display = 'none';
}
);
For the second approach, I even tried to intersect the drawing and to assign a random string as an ID (since the reason that deletion by id does not works, is because the ID is undefined). So under navigation -> bindings I added the object:
circleAnnotation: {
start: function(e) {
var navigation = this.chart.options.navigation;
return this.chart.addAnnotation(
Highcharts.merge({
id: randomStr() //this is a method that generates random string
},
navigation
.annotationsOptions,
navigation
.bindings
.circleAnnotation
.annotationsOptions
)
);
}
}
The both approaches are not working.
You can pass a direct annotation object to the removeAnnotation method:
thischart.removeAnnotation(thischart.currentAnnotation);
Live demo: https://jsfiddle.net/BlackLabel/5ycf3s4o/
API Reference: https://api.highcharts.com/class-reference/Highcharts.Chart#removeAnnotation
Let's say I have N different maps on the screen, I want to be able based on a condition, let s say a value coming from a checkbox or a different control to be able to sync all the map events (zoom/pan/rotation) and unsync them accordingly.
Can this be achieved in OpenLayers 3 using native code?
You can sync maps by listen to their events and setting their changes to the other maps. I wrote a working example, using this as the listener for each map's view's change:center, change:resolution and change:rotation event:
function(evt){
var type = evt.type.split(':');
if (type[0] === 'change' && type.length === 2){
var attribute = type[1];
maps.forEach(function(map){
var value = evt.target.get(attribute);
if (map.getView().get(attribute) !== value){
map.getView().set(attribute, value);
}
});
}
}
I'm working on a project with fairly heavy WMS layers and hit a problem with Alvin's solution. For the first map OL waits for any interaction to end before requesting an updated WMS layer. But for the second map it appears to treat each step triggered by the function as a separate interaction and therefore generates a separate WMS layer request at each step. In my case this was seriously affecting performance.
I've come up with a compromise solution that waits for interaction to end and then animates the second map to match the first. This is a first attempt and could probably be improved:
// attributes to synchronise between maps
var synchedAttributes = ['resolution', 'center']
// call this on moveend
var syncPanZoom = function(maps, evt){
maps.forEach(function(map){
synchedAttributes.forEach(function(attribute) {
var value = evt.target.getView().get(attribute);
if (map.olmap.getView().get(attribute) !== value){
var animateObject = {};
animateObject[attribute] = value;
animateObject.duration = 500;
map.olmap.getView().animate(animateObject)
}
});
});
};
Couple of days ago I found this interesting post at http://www.smartjava.org/content/drag-and-drop-angularjs-using-jquery-ui and applied it into my website. However when I progressively using it there is a bug I identified, basically you can not move an item directly from one div to another's bottom, it has to go through the parts above and progress to the bottom. Anyone can suggest where does it goes wrong? The example is at http://www.smartjava.org/examples/dnd/double.html
Troubling me for days already.....
I did this a bit differently. Instead of attaching a jquery ui element inside the directive's controller, I instead did it inside the directive's link function. I came up with my solution, based on a blog post by Ben Farrell.
Note, that this is a Rails app, and I am using the acts_as_list gem to calculate positioning.
app.directive('sortable', function() {
return {
restrict: 'A',
link: function(scope, elt, attrs) {
// the card that will be moved
scope.movedCard = {};
return elt.sortable({
connectWith: ".deck",
revert: true,
items: '.card',
stop: function(evt, ui) {
return scope.$apply(function() {
// the deck the card is being moved to
// deck-id is an element attribute I defined
scope.movedCard.toDeck = parseInt(ui.item[0].parentElement.attributes['deck-id'].value);
// the id of the card being moved
// the card id is an attribute I definied
scope.movedCard.id = parseInt(ui.item[0].attributes['card-id'].value);
// edge case that handles a card being added to the end of the list
if (ui.item[0].nextElementSibling !== null) {
scope.movedCard.pos = parseInt(ui.item[0].nextElementSibling.attributes['card-pos'].value - 1);
} else {
// the card is being added to the very end of the list
scope.movedCard.pos = parseInt(ui.item[0].previousElementSibling.attributes['card-pos'].value + 1);
}
// broadcast to child scopes the movedCard event
return scope.$broadcast('movedCardEvent', scope.movedCard);
});
}
});
}
};
});
Important points
I utilize card attributes to store a card's id, deck, and position, in order to allow the jQuery sortable widget to grab onto.
After the stop event is called, I immediately execute a scope.$apply function to get back into, what Misko Hevery call,s the angular execution context.
I have a working example of this in action, up in a GitHub Repo of mine.
I have a page, which is used for building queries and running them against different entities (Kind of a query builder/generic search).
The results are displayed in JQGrid, so effectively the same grid will be used for rendering results from different entities.
This results grid has to support context menus, which will differ for each entity. So I need a way to change the context menu as per the entity. Each entity may have different number of menu items in context menu and each item may respond in a different manner (sometimes an alert, sometimes an action spawning in a different tab).
Rendering different menus (through li) is not an issue but attaching the methods to the li is proving to be a challenge. Any pointers will be highly appreciated.
I am using jquery.contextmenu-ui.js .
Following is from a sample that I picked from their (JQGrid) site
function initGrid() {
$("#EntityGrid").contextMenu('cMenu'
,{
bindings: { /* I would like to avoid this and pass all the actions to one method*/
'edit': function (t) {
editRow();
},
'add': function (t) {
addRow();
},
'del': function (t) {
delRow();
}
},
onContextMenu: function (event, menu) {
var rowId = $(event.target).parent("tr").attr("id")
var grid = $("#EntityGrid");
grid.setSelection(rowId);
return true;
}
}
);
}
Thanks,
Avinash
You can use onShowMenu callback of contextMenu instead of static binding using bindings. In the same way the menuId used as the first parameter of contextMenu could be the id of dynamically created div with empty <ul>. The onShowMenu has the form
onShowMenu: function (e, $menu) {
// here one can clear `<ul>` child of $menu
// and append it with "<li>" items
return $menu;
}
In the answer you will find an example of the code which build menu dynamically.
I'm stuck on one particular part of my project which consists of the components mentioned in the title.
I currently have a proof of concept that works the way I want it to work:
Sammy is integrated into the knockout viewmodels (as per the tutorial
on the knockout site)
the views are loaded on demand by a controller
(so I don't have to define every single view on the application page)
In my current situation I instance the viewmodels when the application starts (if I don't instance them, Sammy will not handle the routing). The problem is where the view is loaded and swapped by Sammy. I have to make a call to ko.applyBindings for KO to bind to the view. But its bad practice to repeatedly call applybingings.
My question, how do I bind to my views that are loaded on demand? I can't call ko.applybindings since that would create a memoryleak when the view is loaded more than once.
Here is an example VM with the offending ko.applyBindings:
function serviceInfoVm() {
var self = this;
self.ObjectKey = ko.observable();
self.Service = ko.observable();
self.LoadService = function () {
$.get('ServiceData/Detail', { serviceId: self.ObjectKey() }, function (data) {
self.Service(data);
});
};
$.sammy('#content', function () {
this.get('#/service/:id', function (context) {
var ctx = context;
self.ObjectKey(this.params['id']);
self.LoadService();
$.get('Content/ServiceInfo', function (view) {
ctx.app.swap(view);
ko.applyBindings(self);
});
});
}).run();
};
Anyone with some pointers and/or solutions to this problem?
You have the Sammy code in the viewmodel, which can work great if that viewmodel will be present and you want sub viewmodels and views to be loaded. So I assume that is what you are trying to do. Food for thought ... separate the sammy code into its own module (I call mine router in router.js) and let it manage the navigation separate from any viewmodel.
But back to your code ... you could set up your subviews and subviewmodels and use applybindings on them prior to the sammy.get being called. Basically, you are registering your routes in advance. Then the sammy.get just navigates to the new view, which is already data bound.
Not a solution but another approach:
Ended up abandoning the idea of loading the views dynamically.
Now my views are always present in the page and the visibility is triggered by this code:
var app = function () {
var self = this;
self.State = ko.observable('home');
self.Home = ko.observable(new homepageVm());
self.User = ko.observable(new userInfoVm());
$.sammy(function () {
this.get('#/', function (context) {
self.State('home');
});
this.get('#/info/:username', function (context) {
self.State('user');
self.User().UserName(context.params['username']);
self.User().LoadInfo();
});
}).run();
};
And the div visibility is triggered this way:
<div id="homeView" data-bind="with: Home, visible: State() === 'home'">
This way the ko.applyBindings only needs to be called once when the app starts.
The viewmodel above is bound to our shell page.
More on this here
Calling applyBindings on the specific element in the returned template is an option:
ko.applyBindings(viewModel, htmlNode)
Also see this question with regard to lazy loading templates: knockout.js - lazy loading of templates
And docs here for applyBindings: http://knockoutjs.com/documentation/observables.html