Develop Reference

Unable to Zoom d3 techanjs

I'm using almost same code which has been used in http://techanjs.org/. I was trying to add zooming feature in the chart as the developer has rendered the chart in here. But somehow I'm not able to zoom it. I'm getting error selection is not defined in console. I'm using following code to render the chart. https://paste.fedoraproject.org/paste/7gJq9wKL4h4s862EDuxnQQ. I'm sure I'm doing something wrong in here, I would really appreciate if I get any assistance regarding it as I'm still learning D3.

I'd guess the problem is that you are referencing the variable selection but it isn't defined.
Hence -
selection is not defined
selection is the parameter passed into your bigchart function.
But you then use it in your reset, zoomed functions where it is not defined.
//Zoom Begins
function reset() {
zoom.scale(1);
zoom.translate([0,0]);
selection.call(draw); // this will throw an error
}
function zoomed() {
x.zoomable().domain(d3.event.transform.rescaleX(zoomableInit).domain());
y.domain(d3.event.transform.rescaleY(yInit).domain());
yPercent.domain(d3.event.transform.rescaleY(yPercentInit).domain());
selection.call(draw); // this will throw an error
}
//Zoom Ends
To fix, either pass the selection to the functions as a parameter (like the other functions) - or else make the selection a property of BigChart so that it can be referenced by the reset and zoomedfunctions.
i.e.
// pass selection to the functions as a parameter
function reset(selection) {
zoom.scale(1);
zoom.translate([0,0]);
selection.call(draw);
}
function zoomed(selection) {
x.zoomable().domain(d3.event.transform.rescaleX(zoomableInit).domain());
y.domain(d3.event.transform.rescaleY(yInit).domain());
yPercent.domain(d3.event.transform.rescaleY(yPercentInit).domain());
selection.call(draw);
}
Then when you call the functions obviously you pass in the correct object...e.g.
zoom = selection.call(d3.zoom().on("zoom", zoomed));
rather than
zoom = d3.zoom().on("zoom", zoomed),

Altering external variable from Google Maps' StreetViewService.getPanorama({},callback) method

I am running into trouble with this piece of code since I'm not sure how to fix it. I already asked this in the chats but couldn't figure out myself after some answers.
I want to get Panorama from StreetViewService using the method from the Google Maps javascript API from a StreetViewService getPanorama() method.
The method receives a literal with the coordinates and a radius, and a callback function that receives 2 parameters: data and status.
in that callback you check wether the service returns some images for street view or not, in which case you do one thing or another.
It seems the callback is executed asynchronously or the getPanorama method, executing some kind of ajax behind the scenes.
I'm pasting the code below, but first I explain my intentions. I need to return from one method I made inside a literal that is inside a self made library wether the the request has valid images for that requested coordinates or not by setting a variable to true or false and then at the end returning that value. However, even if I set the variable to true inside that callback anonymous function, when the variable returns, it always has it's initial value without it not being changed.
Here the code. Not everything, just the essential code.
Then my intention is to used the boolean returned to know if I have to switch one button active for some kind of job or not or do some things or not depending of if it returned true or false, Change some style etc as well.
I'd appreciate if you could change my code in a way it could be done. I was told about a callback solution or wrapping it into a promise. However I don't know how to do it. I used promisses in jquery but not in vanilla javascript. I'd like to see how the callback solution could be made as well with this code.
//Library not show for shortenning the example.
streetView: { //This is inside a library
valid_request: false,
event_key: null,
panorama: null,
setStreetView: function(coords, element) {
libMapa.streetView.valid_request = false; // Initialize the value again.
let sv_service = new google.maps.StreetViewService();
var latlng = coords;
sv_service.getPanorama({ // This is a method from Google Map Javascript API.
location: latlng,
radius: 50
}, function(data, status) {
if (status === google.maps.StreetViewStatus.OK) {
if (!libMapa.streetView.panorama) {
libMapa.streetView.panorama = new google.maps.StreetViewPanorama(element);
libMapa.streetView.panorama.setEnableCloseButton(true);
}
libMapa.streetView.panorama.setPano(null);
libMapa.streetView.panorama.setPano(data.location.pano);
libMapa.streetView.panorama.setVisible(true);
libMapa.streetView.valid_request = true;
} else {
alert("No images for this place");
// Otherwise variable stays as FALSE.
}
});
return libMapa.streetView.valid_request;
}
}
/****************************************/
//OUTSIDE THE LIBRARY IN INDEX.HTML
var sv_valid = libMapa.streetView.setStreetView(coords, div_mapa);
//sv_valid still shows false even if it should return true.
if (sv_valid) {
// "pressed" is to control a button as if it was a switch by activatinc and deactivating it.
pressed = false; // It always ends up being false even when it should return true.
element.style.cursor = "default";
libMapa.mapa.unByKey(libMapa.streetView.event_key);
}

Use a callback to do some action or modify some variable after the AJAX call to getPanorama() (and by proxy, setStreetView()) is complete.
Modify setStreetView() to accept a callback parameter and pass it along to getPanorama().
streetView {
// streetView variables etc.
setStreetView: function(coords, element, callback) {
// get ready for the AJAX call etc.
sv_service.getPanorama({
// parameter object
}, function(data, status){
// The getPanorama() callback.
// Do stuff with the data/status here,
// then call the callback function that you passed in to setStreetView.
// You can send data along (e.g. the result of the AJAX call) to the callback.
callback(someResult);
});
}
}
// somewhere else, where you're calling streetView.setStreetView()
var someVar = "foo";
streetView.setStreetView(someCoords, someElement, function(eventualResult){
someVar = eventualResult;
});
Here's a small example: https://jsfiddle.net/_jered/pgftxgf3/
I also highly suggest you do some research on AJAX, asynchronous JavaScript, and callbacks.

Events after clickMouseButton

In one of my tests I have the mouse moved to a specific location and then clickMouseButton() is called. This action is to change the data that is displayed (paging the data.) However, after the click, when I try to get the text in a column of the table to verify that the data changed the data changes back to what was originally displayed and my test fails. My test code is:
return Remote
.moveMouseTo(JE.Buttons.Scrolling(), 5, 100)
.clickMouseButton()
.end(Infinity)
.sleep(500)
.findByXpath('//*[#id="vwNJEAll_grid_header_tbody"]/tr[2]/td[2]/div')
.getVisibleText()
.then(function (result) {
expect(result).not.to.equal(firstSeenJENumber);
});
The code behind JE.Buttons.Scrolling() is:
return Remote
.setFindTimeout(5000)
.findByXpath('//*[#id="vwNJEAll_grid_table_container"]/div[2]/div');
It really seems to me like the locator in Leadfoot is binding to what is on the page when it first loads. Is this the case, and how should I go about getting what I need to happen? I have no other explanation for this, but hopefully you do.

moveMouseTo doesn’t accept a Promise as its first argument, so that moveMouseTo call is wrong and won’t do what you want. The JE.Buttons.Scrolling() call in your example code also occurs immediately (during command chain construction), it doesn’t occur only once moveMouseTo is actually performed.
To retrieve and use an element with your abstraction function, pass the function to then and then use the element:
return Remote
.then(JE.Buttons.Scrolling)
.then(function (element) {
return Remote.moveMouseTo(element, 5, 100);
})
// …remainder of test…

"Function factory" doesn't seem to work, JavaScript

I'm displaying a series of images in a loop, and I'm trying to implement some sort of nudity filter so I'm using nude.js, a library that can somewhat detect nudity. Here's the code:
// we're inside a loop
$(".images").prepend($("<img>").attr({src: whatever, id: uniqueid}).load(function(e) {
nude.load(e.target.id);
nude.scan(function(result) { if (!result) $(e.target).detach(); });
});
However, it detaches all of the wrong images because nude.js is slow and it completes after the loop has gone on to the later iterations, detaching those images instead of the one it was working on.
I've tried using a function factory:
function generateCallback(arg) {
return function(result) { if (!result) $(arg).detach(); };
}
and
nude.scan( generateCallback(e.target) )
but the same thing happens.
What I want is a load event that will remove the image if it seems to contain nudity. How can I do this properly?
EDIT: nude.js works like this:
nude.load(imageid);
nude.scan(callback); // it'll pass true or false into the callback
another edit: accidentally omitted the id setting from the code I posted, but it was there in my real code, so I added it here.

I suspect the case here is that this kind of sequential processing won't work with nude.js.
Looking at the nude.js code, I think your problem is occurring in the call to nude.scan. nude.js has a variable that stores the function to invoke after the scan has completed. When calling nude.scan(callback), this variable is set to be callback.
From your PasteBin, it seems as though the callback gets assigned as expected on the first call, but on the second and subsequent calls, it gets replaced, hence why the second image is detached and not the first.

What happends to your script, is that the e var is global to the function and so after each loop it gets replaced with the new one. So when the first image is scanned, e already became the event of the second image, which get detached.
To solve your problem, use closures. If you want to know more about closures, have a look here.
Otherway, here's the solution to your problem :
$(".images").prepend($("<img>").attr({src: whatever, id: uniqueid}).load(function(e) {
(function(e) {
nude.load(e.target.id);
nude.scan(function(result) { if (!result) $(e.target).detach(); });
}) (e);
});
EDIT: AS nick_w said, there is var that contains the callback and probably gets replaced each time so this is why it isn't the right picture getting detached. You will probably have to modify the script yourself

Can I control the order in which javascript / jQuery events fire?

Background
I've got asp.net webform with a grid, and when users update textboxes in that grid, the onchange event kicks off a WebMethod call and updates the rest of the changed row. Nothing is saved at that time -- we're just updating the UI.
To commit the changes, you click the save button.
This actually works reliably in almost every scenario. However, there is one very persistant one that it feels like I should be able to solve, but it's time to call in the specialists.
The Problem Scenario
I'm using jQuery to capture the enter key, and unfortunately that event fires first, causing the page to submit before the callback completes. The row is not updated correctly. Stale and bewildering data is saved.
Update
I don't think you can make the enter behavior depend on the callback, because you could save without changing a row. In that case, if you didn't change a row, it would never save.
Now if there was some way to inspect javascript's internal list of things to do, or maybe create my own and then manage it somehow, that would work. But that's some heavy lifting for something that should be easy. So unless an expert tells me otheriwse, I have to assume that's wrong.
Attempts
Right now I'm using the built-in jQuery events and I've got this elaborate setTimeout persisting the fact that a save was attempted, pausing long enough for the WebMethod to at least get called, and relying on the callback to do the submit. But it turns out javascript ansychrony doesn't work the way I hoped, and the onchange event doesn't even fire until that chunk of code completes. That was surprising.
I was thinking I could use my own little object to queue up these events in the right order and find a clever way to trigger that, etc.
This all seems like the wrong direction. Surely this is insane overkill, this is a common problem and I'm overlooking a simple solution because I don't work in javascript 24/7.
Right?
Code
Here's what I've got right this minute. This obviously doesn't work -- I was trying to take advantage of the async nature of jquery, but all of this apparently has to conclude before the row's onchange event event fires:
$(document).bind("keypress", function (e) {
if (e.keyCode == 13) {
handleEnter();
return false; //apparently I should be using e.preventDefault() here.
}
});
function handleEnter() {
setTimeout(function () {
if (recalculatingRow) { //recalculatingRow is a bit managed by the onchange code.
alert('recalculating...');
return true; //recur
}
//$('input[id$="ButtonSave"]').click();
alert('no longer recalculating. click!');
return false;
}, 1000);
}
And then a typical row looks like this. Note that I'm not using jquery to bind this:
<input name="ctl00$MainContent$GridOrderItems$ctl02$TextOrderItemDose" type="text" value="200.00" maxlength="7" id="ctl00_MainContent_GridOrderItems_ctl02_TextOrderItemDose" onchange="recalculateOrderItemRow(this);" style="width:50px;" />
I could post the code for recalculateOrderItemRow, but it's really long and right now the problem is that it doens't fire until the after keypress event concludes.
Update Dos
According to Nick Fitzgerald (and man is that a cool article) the use of setTimeout should cause this to become async. Digging further into interactions between setTimeout and jQuery, as well as interactions between normal javascript events and jQuery events.

Preventing ENTER shouldn't be causing you so much trouble! Make sure you have something like this on your code:
$(document).on('keydown', 'input', function(e) {
if(e.keyCode == 13) {
e.preventDefault();
}
});
UPDATE
It looks like you do want to save on ENTER, but only after the UI is updated on change. That is possible. You could use a flag a Matthew Blancarte suggested above, trigger save from the change callback, and get rid of the setTimeout.
But I wouldn't recommend that. You are better off relying solely on the save button for saving. If you don't, your users will have to wait for two async operations to complete before saving is finished. So you'd have to block the UI, or keep track of all async operations, aborting some as needed. I think it's not worthy, ENTER becomes less intuitive for the users if saving takes too long.

The hideous mass of workarounds below, which effectively took me all day today and half of yesterday to write, seems to solve every permutation.
The amusing thing is that enter itself doesn't trigger onchange, if you call e.preventDefault(). Why would it? The change doesn't actually happen until the default behavior of clicking the save button occurs.
Very little else about this is amusing.
//Used in handleEnter and GridOrderItems.js to handle a deferred an attempt to save by hitting enter (see handleEnter).
var isSaving = false;
var saveOnID = '';
//When one of the fields that trigger WebMethods get focus, we put the value in here
//so we can determine whether the field is dirty in handleEnter.
var originalVal = 0;
//These fields trigger callbacks. On focus, we need to save their state so we can
//determine if they're dirty in handleEnter().
$('[id$=TextOrderItemDose], [id$=TextOrderItemUnits]').live("focus", function() {
originalVal = this.value;
});
$(document).bind("keypress", function (e) {
if (e.keyCode == 13) { //enter pressed.
e.preventDefault();
handleEnter();
}
});
//Problem:
//In the products grid, TextOrderItemDose and TextOrderItemUnits both have js in their onchange events
//that trigger webmethod calls and use the results to update the row. Prsssing enter is supposed to
//save the form, but if you do it right after changing one of those text fields, the row doesn't always
//get updated due to the async nature of js's events. That leads to stale data being saved.
//Solution:
//First we capture Enter and prevent its default behaviors. From there, we check to see if one of our
//special boxes has focus. If so, we do some contortions to figure out if it's dirty, and use isSaving
//and saveOnID to defer the save operation until the callback returns.
//Otherwise, we save as normal.
function handleEnter() {
var focusedElement = $("[id$=TextOrderItemDose]:focus, [id$=TextOrderItemUnits]:focus")
//did we press enter with a field that triggers a callback selected?
if (isCallbackElement(focusedElement) && isElementDirty(focusedElement)) {
//Set details so that the callback can know that we're saving.
isSaving = true;
saveOnID = focusedElement.attr('id');
//Trigger blur to cause the callback, if there was a change. Then bring the focus right back.
focusedElement.trigger("change");
focusedElement.focus();
} else {
forceSave();
}
}
function isCallbackElement(element) {
return (element.length == 1);
}
function isElementDirty(element) {
if (element.length != 1)
return false;
return (element.val() != originalVal);
}
function forceSave() {
isSaving = false;
saveOnID = '';
$('input[id$="ButtonSave"]').click();
}
This gets called in the change event for the textboxes:
function recalculateOrderItemRow(textbox) {
//I'm hiding a lot of code that gathers and validates form data. There is a ton and it's not interesting.
//Call the WebMethod on the server to calculate the row. This will trigger a callback when complete.
PageMethods.RecalculateOrderItemRow($(textbox).attr('id'),
orderItemDose,
ProductItemSize,
orderItemUnits,
orderItemUnitPrice,
onRecalculateOrderItemRowComplete);
}
And then, at the end of the WebMethod callback code we pull the updated form values out, put the caret where it needs to be using jquery.caret, and check to see if we need to force a save:
function onRecalculateOrderItemRowComplete(result) {
var sender, row;
sender = $('input[id="' + result.Sender + '"]');
row = $(sender).closest('tr');
row.find('input[id$="TextOrderItemDose"]').val(result.Dose);
row.find('input[id$="TextOrderItemUnits"]').val(result.Units);
row.find('span[id$="SpanTotalPrice"]').html(formatCurrency(result.TotalPrice));
calculateGrandTotalPrice();
$(document.activeElement).select();
if (isSaving && saveOnID == result.Sender) {
forceSave();
}
}
result.Sender is the ID of the calling control, which I stuffed into the WebMethod call and then returned. saveOnID may not be perfect, and it might actually be even better to maintain a counter of active/uncallback-ed WebMethod calls to be totally sure that everything wraps up before save. Whew.

Can you post your javascript? Sounds like you're on the right track. I would change my OnChange events to increment a variable before making the AJAX call. I'll call the variable inProcess and initialize it to zero. When the AJAX call comes back, I would update the inProcess to the current value minus one. On the Enter key event, I would check to that inProcess equals zero. If not, you could either warn the user or set a timeout to try again in a bit.

You could unbind the Enter key capture while you are in the onChange event, then rebind it at the end of the callback function. If you post some code, I could give a more specific answer.

It sounds like you shouldn't be calling the WebMethod asynchronously. Call it synchronously, and on success, save your data.