I'm working on a website for a school project containing a button which you need to press. When pressed, the button takes a value from the database, child 'aantal' and adds 1. When that is done, it re-uploads it back to the database. One page further, you can see the live number of that child. The problem is, this is not working on iOS 9 or lower and on OSX Yosemite or lower. On android and windows it works fine.
Reusable code;
This is just a button. If you press the button it adds 1 on the int. This is very strange because it doesn't doesn't work on the OS mentioned above.
<script src="https://www.gstatic.com/firebasejs/3.6.9/firebase.js"></script>
<script language="JavaScript">
// Initialize Firebase
var config = {
apiKey: //API KEY,
authDomain: //FIRBASE DOMAIN,
databaseURL: //DATABASE URL,
storageBucket: //STORAGE BUCKET,
messagingSenderId: //MESGSENDID
};
firebase.initializeApp(config);
var number;
var database = firebase.database().ref().child('aantal');
function buy() {
database.on('value', snap => number = snap.val());
var count = parseInt(number, 10) + 1;
database.set(count);
}
</script>
This code will not work, initialise own Firebase project for testing.
For security reasons I removed my details.
Edit
Turns out Safari (9.1/iOS 9.3 and below) doesn't support arrow functions.
Changing database.on('value', snap => number = snap.val()); to database.on('value', function(snap) { number = snap.val()}); fixed the issue.
Well I mean, that code shouldn't work anywhere.
function buy() {
database.on('value', snap => number = snap.val());
var count = parseInt(number, 10) + 1;
database.set(count);
}
Firebase is asynchronous, and you're not waiting for it to actually load number from the database.
This should work.
function buy() {
database.on('value', snap => {
number = snap.val();
var count = parseInt(number, 10) + 1;
database.set(count);
});
}
I don't know whether this is actually the issue you're having or if you just wrote this in your example. Also, when incrementing values you should be using Transactions.
function buy() {
database.transaction(function(value) {
if (value) {
value++;
}
return value;
});
}
Related
This works perfectly in Android.
public async Task<double> UploadData()
{
double steps = 0.0;
await _healthData.GetSteps((totalSteps) =>
{
SentrySdk.CaptureMessage("totalSteps = " + totalSteps);
MainThread.BeginInvokeOnMainThread(() =>
{
steps = totalSteps;
//Task.Delay(1000);
});
});
SentrySdk.CaptureMessage("UploadData steps = " + steps);
var fitness = new Fitness();
fitness.Steps = steps;
await _restService.SaveItemAsync(fitness, true);
return steps;
}
In iOS, totalSteps is correct, but steps is still 0 when fitness.Steps = steps runs. Bottom line, I can't get the totalSteps value from inside the _healthData.GetSteps((totalSteps) operation. The Android Google Fit and iOS HealthKit API calls run with completion handlers.
At this stage, I'm just trying to figure out how to upload data (steps, calories, active minutes, distance) to my server.
Does anyone know how to make this work? I can display all the data (steps, calories, active minutes, distance) in a View using an ObservableCollection.
I got this to work by embedding the calls like so.
_healthData.GetHealthPermissionAsync((result) =>
{
if (result)
{
_healthData.FetchSteps((totalSteps) =>
{
_healthData.FetchMetersWalked((metersWalked) =>
{
_healthData.FetchActiveMinutes((activeMinutes) =>
{
_healthData.FetchActiveEnergyBurned((caloriesBurned) =>
{
var fitness = new Fitness();
fitness.Steps = totalSteps;
fitness.Calories = caloriesBurned;
fitness.Distance = metersWalked;
fitness.Minutes = activeMinutes;
_restService.SaveItemAsync(fitness, true);
});
});
});
});
}
});
Wanted to check how many instances are running and control the number of instances running in one exe electron bundle. Let us say I wanted to allow only three instances running for the one exe bundle. I am not able to do this.
Current Behavior:
Only one and remaining can block. Or open for any number of instances. We need to control only three instances running, not more than that.
Example:
const { app } = require('electron')
let myWindow = null
const gotTheLock = app.requestSingleInstanceLock()
if (!gotTheLock) {
app.quit()
} else {
app.on('second-instance', (event, commandLine, workingDirectory) => {
// Someone tried to run a second instance, we should focus our window.
if (myWindow) {
if (myWindow.isMinimized()) myWindow.restore()
myWindow.focus()
}
})
// Create myWindow, load the rest of the app, etc...
app.on('ready', () => {
})
}
You can try with the following code to know how many windows have been opened.
const count = BrowserWindow.getAllWindows().length;
To check visible windows, you can try the following code
let count = BrowserWindow.getAllWindows()
.filter(b => {
return b.isVisible()
}).length
Once you get the number of instances, based upon the condition for number of instance, ie. if it is more than 3, you can quit using app.quit().
You can make each instance write to a file (increment a counter for example) when the instance starts and when it exits. (decrement the counter). You should check that file to see if the maximum number of instances are running
import { app } from "electron";
import path from "path";
import fs from "fs";
const MAX_APP_INSTANCES = 3;
const INSTANCE_COUNT_FILE_PATH = path.join(
app.getPath("userData"),
"numOfInstances"
);
// utils to read/write number of instances to a file
const instanceCountFileExists = () => fs.existsSync(INSTANCE_COUNT_FILE_PATH);
const readInstanceCountFile = () =>
parseInt(fs.readFileSync(INSTANCE_COUNT_FILE_PATH, "utf-8"));
const writeInstanceCountFile = (value) =>
fs.writeFileSync(INSTANCE_COUNT_FILE_PATH, value);
const incInstanceCountFile = () => {
const value = readInstanceCountFile() + 1;
writeInstanceCountFile(value.toString());
};
const decInstanceCountFile = () => {
const value = readInstanceCountFile() - 1;
writeInstanceCountFile(value.toString());
};
// logic needed to only allow a certain number of instances to be active
if (instanceCountFileExists() && readInstanceCountFile() >= MAX_APP_INSTANCES) {
app.quit();
} else {
if (!instanceCountFileExists()) {
writeInstanceCountFile("1");
} else {
incInstanceCountFile();
}
app.on("quit", () => decInstanceCountFile());
}
Note: this is solution is somewhat hacky. For example, the quit event is not guaranteed to fire when the Electron app exits
I am trying to get audio capture from the microphone working on Safari on iOS11 after support was recently added
However, the onaudioprocess callback is never called. Here's an example page:
<html>
<body>
<button onclick="doIt()">DoIt</button>
<ul id="logMessages">
</ul>
<script>
function debug(msg) {
if (typeof msg !== 'undefined') {
var logList = document.getElementById('logMessages');
var newLogItem = document.createElement('li');
if (typeof msg === 'function') {
msg = Function.prototype.toString(msg);
} else if (typeof msg !== 'string') {
msg = JSON.stringify(msg);
}
var newLogText = document.createTextNode(msg);
newLogItem.appendChild(newLogText);
logList.appendChild(newLogItem);
}
}
function doIt() {
var handleSuccess = function (stream) {
var context = new AudioContext();
var input = context.createMediaStreamSource(stream)
var processor = context.createScriptProcessor(1024, 1, 1);
input.connect(processor);
processor.connect(context.destination);
processor.onaudioprocess = function (e) {
// Do something with the data, i.e Convert this to WAV
debug(e.inputBuffer);
};
};
navigator.mediaDevices.getUserMedia({audio: true, video: false})
.then(handleSuccess);
}
</script>
</body>
</html>
On most platforms, you will see items being added to the messages list as the onaudioprocess callback is called. However, on iOS, this callback is never called.
Is there something else that I should do to try and get it called on iOS 11 with Safari?
There are two problems. The main one is that Safari on iOS 11 seems to automatically suspend new AudioContext's that aren't created in response to a tap. You can resume() them, but only in response to a tap.
(Update: Chrome mobile also does this, and Chrome desktop will have the same limitation starting in version 70 / December 2018.)
So, you have to either create it before you get the MediaStream, or else get the user to tap again later.
The other issue with your code is that AudioContext is prefixed as webkitAudioContext in Safari.
Here's a working version:
<html>
<body>
<button onclick="beginAudioCapture()">Begin Audio Capture</button>
<script>
function beginAudioCapture() {
var AudioContext = window.AudioContext || window.webkitAudioContext;
var context = new AudioContext();
var processor = context.createScriptProcessor(1024, 1, 1);
processor.connect(context.destination);
var handleSuccess = function (stream) {
var input = context.createMediaStreamSource(stream);
input.connect(processor);
var recievedAudio = false;
processor.onaudioprocess = function (e) {
// This will be called multiple times per second.
// The audio data will be in e.inputBuffer
if (!recievedAudio) {
recievedAudio = true;
console.log('got audio', e);
}
};
};
navigator.mediaDevices.getUserMedia({audio: true, video: false})
.then(handleSuccess);
}
</script>
</body>
</html>
(You can set the onaudioprocess callback sooner, but then you get empty buffers until the user approves of microphone access.)
Oh, and one other iOS bug to watch out for: the Safari on iPod touch (as of iOS 12.1.1) reports that it does not have a microphone (it does). So, getUserMedia will incorrectly reject with an Error: Invalid constraint if you ask for audio there.
FYI: I maintain the microphone-stream package on npm that does this for you and provides the audio in a Node.js-style ReadableStream. It includes this fix, if you or anyone else would prefer to use that over the raw code.
Tried it on iOS 11.0.1, and unfortunately this problem still isn't fixed.
As a workaround, I wonder if it makes sense to replace the ScriptProcessor with a function that takes the steam data from a buffet and then processes it every x milliseconds. But that's a big change to the functionality.
Just wondering... do you have the setting enabled in Safari settings? It comes enabled by default in iOS11, but maybe you just disabled it without noticing.
I have been struggling with this piece of javascript for some time now. I have read different, and similar, posts on the subject but I can't find anything that seems to lead me in the right direction of solving my problem.
I need to call the value of the variables from the watchPosition (and getCurrentPosition) method , set them as global and then call them inside of the function initMap().
The code is working but watchPosition reloads the Google map (this appears to happen when i change the browser/switch between tabs). I can't get the global variables to catch the value from the methods below (inside updateMarker).
How do I set the values from:
mon_lat = +position.coords.latitude;
mon_long = +position.coords.longitude;
to become global?
My main question is, more or less: how can i load the script without updating function initMap()? I would like it so that the navigator.geolocation.watchPosition() method updates automatically.
$(document).ready(function() {
updateMarker();
});
var mon_lat = null;
var mon_long = null;
var start_lat = null;
var start_long = null;
function updateMarker() {
// Get positions
if (navigator.geolocation) {
// Get current position
navigator.geolocation.watchPosition(
function (position) {
mon_lat = +position.coords.latitude;
mon_long = +position.coords.longitude;
initMap(mon_lat, mon_long);
}
);
// Get starting position
navigator.geolocation.getCurrentPosition(
function (position) {
start_lat = +position.coords.latitude;
start_long = +position.coords.longitude;
initMap(start_lat, start_long);
}
);
}
}
function initMap() {
// Display the map
map = new google.maps.Map(document.getElementById('map'), {
center: {lat: mon_lat, lng: mon_long},
zoom: 10,
mapTypeControl:false
});
}
I'm trying to code on google app and I've encountered one issue. For example, let's consider this example code on google website ( link's here https://developers.google.com/apps-script/class_formpanel )
function doGet() {
var app = UiApp.createApplication();
var form = app.createFormPanel();
var flow = app.createFlowPanel();
flow.add(app.createTextBox().setName("textBox"));
flow.add(app.createListBox().setName("listBox").addItem("option 1").addItem("option 2"));
flow.add(app.createSubmitButton("Submit"));
form.add(flow);
app.add(form);
return app;
}
function doPost(eventInfo) {
var app = UiApp.getActiveApplication();
app.add(app.createLabel("Form submitted. The text box's value was '" +
eventInfo.parameter.textBox +
"' and the list box's value was '" +
eventInfo.parameter.listBox + "'"));
return app;
}
My issue is that I want to select multiple values on the listbox. I change then line 6 in
flow.add(app.createListBox(true).setName("listBox").addItem("option 1").addItem("option 2"));
to allow multiple selection. But the result is that only the last selected value is taken, preventing multiple selections. Apparently, it is due to the submitButton. I need to keep the formPanel because on a further code I'll like to combine uploading files and listBox multiple selection. How may I fix that? Thank you a lot
As a complement to Mogsdad's answer, note that this bug / issue is only concerning the doPost structured handler... if you don't need the file upload feature you could use a simple doGet + handler with callbackElement and in this case the multiselect list is available and works as expected.
test function :
function doGet() {
var app = UiApp.createApplication().setTitle('test listBox');
var panel = app.createHorizontalPanel().setStyleAttribute('padding','40px');
var sHdlr = app.createServerHandler('validateList').addCallbackElement(panel);
var items = ['category 1','category 2','category 3'];
var list1 = app.createListBox(true).setName('list1');
for(var i =0;i<items.length;++i){list1.addItem(items[i],i)}
panel.add(list1).add(app.createButton('validate',sHdlr));
app.add(panel);
return app;
}
function validateList(e){
var app = UiApp.getActiveApplication();
app.add(app.createLabel("Value(s) in list : "+e.parameter.list1).setStyleAttribute('margin-left','40'));
return app;
}
and below is a working example of the workaround described in the issue tracker.
I used a textBox to show the process, set it to visible(false) or use a hidden widget in a 'real' app. ( Test available here )
function doGet() {
var app = UiApp.createApplication().setTitle('test listBox');
var panel = app.createHorizontalPanel().setStyleAttribute('padding','40px');
var listHandler = app.createServerHandler('updlistVal').addCallbackElement(panel);
var items = ['category 1','category 2','category 3'];
var list1 = app.createListBox(true).setName('list1').addChangeHandler(listHandler);
for(var i =0;i<items.length;++i){list1.addItem(items[i])}
panel.add(list1).add(app.createTextBox().setText(items[0]).setId('listboxVal').setName('listboxVal').setWidth('200'));// set a default value in case the user is happy with that and doesn't touch the listBox
var submitBtn = app.createSubmitButton('test').setStyleAttribute('margin-left','40');
app.add(app.createFormPanel().add(panel.add(submitBtn)));
return app;
}
function doPost(e){
var app = UiApp.getActiveApplication();
app.add(app.createLabel().setStyleAttribute('padding','40').setText("Submitted value(s) from list : "+e.parameter.listboxVal));
return app;
}
function updlistVal(e){
var app = UiApp.getActiveApplication();
app.getElementById('listboxVal').setValue(e.parameter.list1);
return app;
}
EDIT 2 :
As Mentioned in the comments on this post we must find a way to prevent going through the submission before the value of the hidden/text widget has been updated with a valid value. The "default value" I used above is a possible solution, another one is to use a client handler to validate the submit button only if the listValue (or its value in the hidden widget) is right. Here is a code that does it (only the doGet is reproduced, all other functions being identical.
function doGet() {
var app = UiApp.createApplication().setTitle('test listBox');
var panel = app.createHorizontalPanel().setStyleAttribute('padding','40px');
var submitBtn = app.createSubmitButton('test').setStyleAttribute('margin-left','40').setEnabled(false);
var listHandler = app.createServerHandler('updlistVal').addCallbackElement(panel);
var items = ['category 1','category 2','category 3'];
var listVal = app.createTextBox().setText('not defined yet').setId('listboxVal').setName('listboxVal').setWidth('200');
var list1 = app.createListBox(true).setName('list1').addChangeHandler(listHandler).addItem('choose one or more item(s)');
for(var i =0;i<items.length;++i){list1.addItem(items[i])}
var clientH = app.createClientHandler().forTargets(submitBtn).setEnabled(true).validateMatches(list1, 'category');
list1.addClickHandler(clientH);
panel.add(list1).add(listVal);// set a default value in case the user is happy with that and doesn't touch the listBox
app.add(app.createFormPanel().add(panel.add(submitBtn)));
return app;
}
Using the hidden widget as validation source causes a small issue as we need to click twice on the listBox to make it work... in case there are other questions on the form this will be solved by triggering the client handler with every other widgets so that the double click won't be necessary anymore but this is becoming a bit "out of subject" I'm afraid.
EDIT 3 :
just for the fun of it, a last version that works apparently without issue...
test here
function doGet() {
var app = UiApp.createApplication().setTitle('test listBox');
var panel = app.createHorizontalPanel().setStyleAttribute('padding','40px');
var submitBtn = app.createSubmitButton('test').setStyleAttribute('margin-left','40').setEnabled(false).setId('sbmt');
var wait = app.createImage('https://dl.dropboxusercontent.com/u/211279/loading3T.gif').setId('wait').setVisible(false);
var listHandler = app.createServerHandler('updlistVal').addCallbackElement(panel);
var items = ['category 1','category 2','category 3'];
var listVal = app.createTextBox().setText('not defined yet').setId('listboxVal').setName('listboxVal').setWidth('200');
var list1 = app.createListBox(true).setName('list1').addChangeHandler(listHandler).addItem('choose one or more item(s)');
for(var i =0;i<items.length;++i){list1.addItem(items[i])}
var clientH = app.createClientHandler().forTargets(wait).setVisible(true).forTargets(submitBtn).setEnabled(false);
list1.addChangeHandler(clientH);
panel.add(list1).add(listVal);// set a default value in case the user is happy with that and doesn't touch the listBox
app.add(app.createFormPanel().add(panel.add(submitBtn).add(wait)));
return app;
}
function doPost(e){
var app = UiApp.getActiveApplication();
app.add(app.createLabel().setStyleAttribute('padding','40').setText("Submitted value(s) from list : "+e.parameter.listboxVal));
return app;
}
function updlistVal(e){
var app = UiApp.getActiveApplication();
app.getElementById('listboxVal').setValue(e.parameter.list1);
app.getElementById('sbmt').setEnabled(true);
app.getElementById('wait').setVisible(false);
return app;
}
This is a known bug in the issue tracker, Issue 959. Visit and star it for updates.
It's been known and "worked on" since Dec 2011, if you believe the notes added by the support team. Other users have provided a work-around, and a modified version of it appears below.
The idea is to attach a handler function to the ListBox, which will receive all the selected items from the ListBox. The handler will then write those values to a hidden element in the form. When the form is submitted, the list of selections will be available to the doPost(), via the hidden element.
...
var listbox = app.createListBox(true).setName("listBox").addItem("option 1").addItem("option 2");
flow.add(listbox);
// Issue 959 ListBox Workaround: http://code.google.com/p/google-apps-script-issues/issues/detail?id=959
var listboxHidden= app.createHidden("listboxHidden", "").setId("listboxHidden");
flow.add(listboxHidden);
var fixListBoxHandler = app.createServerHandler('fixListBoxHandler');
fixListBoxHandler.addCallbackElement(listbox);
listbox.addChangeHandler(fixListBoxHandler);
...
}
function fixListBoxHandler(e) {
var app = UiApp.getActiveApplication();
app.getElementById('listboxHidden').setValue(e.parameter.listbox);
return app;
}
NOTE: Unfortunately, this work-around is time-sensitive; it can take several seconds for the handler to update the hidden value. If the submit button is hit before the handler completes its job, then post() receives what was in the hidden element before the call to the handler.