I've been using rails for past few days and wanted to know what is best way to show image previews before upload in rails & carrierwave.
I came across a few options like using plupload or jquery file upload or using uploadify.
If you only need image preview in a form before upload, you (as me) will see that JQuery Upload plugin is just too much complex and not so easy to run properly (I was able to see the preview, but then I couldn't upload the picture).
http://saravani.wordpress.com/2012/03/14/preview-of-an-image-before-it-is-uploaded/
It's simple and fast to code.
I put the code here just in case the source dies:
Script:
<!-- Assume jQuery is loaded -->
<script>
function readURL(input) {
if (input.files && input.files[0]) {
var reader = new FileReader();
reader.onload = function (e) {
$('#img_prev')
.attr('src', e.target.result)
.width(150)
.height(200);
};
reader.readAsDataURL(input.files[0]);
}
}
</script>
In the HTML:
<!--[if IE]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>
<![endif]-->
</head>
<body>
<input type='file' onchange="readURL(this);" />
<img id="img_prev" src="#" alt="your image" />
</body>
You can use the plugin jQuery File Upload which it's a full solution, but if you need something less robust, you can also try using FileReader directly, like this, so you can customize the functionality to whatever you need.
According to the documents image_cache is showing what you are uploading.
<%= f.hidden_field :image_cache %>
Related
I am trying to load image files to my server. To do that I found this code as part of an ajax-example:
<!DOCTYPE html>
<html>
<head>
<title> Ajax JavaScript File Upload Example </title>
</head>
<body>
<!-- HTML5 Input Form Elements -->
<input id="fileupload" type="file" name="fileupload" />
<button id="upload-button" onclick="uploadFile()"> Upload </button>
<!-- Ajax JavaScript File Upload Logic -->
<script>
async function uploadFile() {
let formData = new FormData();
formData.append("file", fileupload.files[0]);
await fetch('/upload.php', {
method: "POST",
body: formData
});
alert('The file has been uploaded successfully.');
}
</script>
</body>
</html>
As I understand it, await fetch('/upload.php', tries to start a program named upload.php on the receiver, my server.
Aren't there supposed to be a domain-name? I mean, where is the upload-
file placed? This will only work if the user is also the owner of the domain, right?
Also, assume my program is on "https://DontTouchThis.com/uploads/", a subdirectory. Even users with this domain will not be able to start it.
I am confused.
Going through the docs, it seems like Sapper's template.html only has these tags available:
%sapper.base%
%sapper.styles%
%sapper.head%
%sapper.html%
%sapper.scripts
What I'd love to have is the current page's slug to use it like so:
<!-- bottom of template.html -->
<img src="https://piratepx.com/page={currentPageSlug}"
alt="" style="display:none;"/>
</body>
</html>
It doesn't need to be available to JS, just added in the HTML.
I'm exporting to static and this would be a trivial task with most Static Site Generators but I can't find the obvious solution with Sapper.
Considering you are using Sapper I would do this in _layout.svelte instead:
<script>
import { stores } from '#sapper/app';
const { page } = stores();
$: currentPageslug = $page.params.slug
</script>
<img src="https://piratepx.com/page={currentPageSlug}" alt=""/>
With this technique you can also add a default value, or some condition in case there is no slug.
I have a web app that creates pdf files and shows a preview. Like so
...
<body>
<iframe id="preview" src=""></iframe>
<script src="jspdf.min.js"></script>
<script>
var doc = new jsPDF()
doc.text(5, 5, 'Hello, world!')
document.getElementById("preview").src = doc.output("datauristring")
</script>
</body>
...
Problem is, it doesn't work e.g. in IE. So I want to make a desktop app using electron.js. According to this post: >Electron PDF viewer there is a pdf viewer in electron, but the iframe (or webview) is always empty.
Is it somehow possible?
I'm trying to embed a column3d chart from fusioncharts in my MonoTouch project using UIWebView. I've added the necessary outlets and tested by using loadrequest to load a url and loadHtmlString to format a simple line of text. This works fine. I even tested that fusionchart works correctly on my browser using the below code and it does.
I have a folder named "charts" in my MonoTouch project that contains, Column3d.swf, jquery.min.js, FusionCharts.js, FusionCharts.HC.js and FusionCharts.HC.Charts.js.
In my
ViewDidLoad
string htmlString = "<html>
<head>
<script type=\"text/javascript\"src=\"Charts/jquery.min.js\">
</script>
<script type=\"text/javascript\" src=\"Charts/FusionCharts.js\">
</script>
<script type=\"text/javascript\" src=\"Charts/FusionCharts.HC.js\">
</script>
<script type=\"text/javascript\" src=\"Charts/FusionCharts.HC.Charts.js\">
</script>
</head>
<body>
<div id=\"chartContainer\">FusionCharts will load here!
</div>
<script type=\"text/javascript\"> var myChart = new FusionCharts( \"Charts/Column3D.swf\", \"myChartId\", \"400\", \"300\", \"0\", \"1\" );myChart.setXMLUrl(\"Charts/Data.xml\");
myChart.render(\"chartContainer\");
</script>
</body>
</html>";
this.webView.LoadHtmlString (htmlString, new NSUrl ("./Charts", true));
/*string htmlString = "<html><head></head><body><span style=\"font-weight: bold;\">This</span> " +
"<span style=\"text-decoration: underline;\">is</span> <span style=\"font-style: italic;\">some formatted</span> " +"<span style=\"font-weight: bold;text-decoration: underline;\">text!</span><br></body></html>";*/ //works
//this.webView.LoadHtmlString (htmlString, null); //works
Data.xml
<chart caption='Weekly Sales Summary'
xAxisName='Week' yAxisName='Amount' numberPrefix='$'>
<set label='Week 1' value='14400' />
<set label='Week 2' value='19600' />
<set label='Week 3' value='24000' />
<set label='Week 4' value='15700' />
</chart>
Can someone explain how I can get this working? Thanks in advance.
EDIT: I also tried
string htmlString = "<html><head> <title>Creating Pure JavaScript chart</title><script type=\"text/javascript\" src=\"charts/FusionCharts.js\"></script></head> <body><div id=\"chartContainer\">FusionCharts will load here!</div> <script type=\"text/javascript\">FusionCharts.setCurrentRenderer('javascript');var myChart = new FusionCharts( \"charts/Column3D.swf\", \"myChartId\", \"400\", \"300\", \"0\", \"1\" );myChart.setXMLData(\"<chart><set label='Data1' value='1' /></chart>\"); myChart.render(\"chartContainer\"); </script></body> </html>";
where i force the renderer to use javascript and set the chart parameters in the string to no avail. Anyone?
I solved my issue and thought I would post it should someone run into a similar issue.
The first thing I did was to right click on each of my javscript files ie FusionCharts.js, FusionCharts.HC.js and FusionCharts.HC.Charts.js and set their build type to content.
I then told Monotouch the build path for the charts would be contained in the charts folder by declaring
string path = NSBundle.MainBundle.BundlePath + "/Charts/";
Since I declare i am going to look in the Charts folder for related files, I then had to amend my htmlString by removing the "charts" keyword reference from all the "src" as below (since we are already lo.
string htmlString = "<html>
<head>
<script type=\"text/javascript\" src=\"jquery.min.js\">
</script>
<script type=\"text/javascript\" src=\"/FusionCharts.js\">
</script>
<script type=\"text/javascript\" src=\"/FusionCharts.HC.js\">
</script>
<script type=\"text/javascript\" src=\"FusionCharts.HC.Charts.js\">
</script>
</head>
<body>
<div id=\"chartContainer\">FusionCharts will load here!
</div>
<script type=\"text/javascript\"> var myChart = new FusionCharts(\"Column3D.swf\", \"myChartId\", \"400\", \"300\", \"0\", \"1\" );myChart.setXMLUrl(\"Charts/Data.xml\");
myChart.render(\"chartContainer\");
</script>
</body>
</html>";
I then call the loadHtml string method as below with the second argument pointing to the path that contains the javascript files.
this.webView.LoadHtmlString(htmlString, new NSUrl(path, true));
I even tested that fusionchart works correctly on my browser using the below code and it does.
Did you test this with an iOS device running Safari ?
project that contains, Column3d.swf,
That looks like a Flash file and iOS (and WebKit) does not support flash.
The website hints of an HTML5 version - so if they support flash-less browser then you should be able to do what you want using MonoTouch (or anything in iOS) using FusionChart. Otherwise you might need to look at other charting products (or a server-side solution).
FusionCharts had put out a blog post showing how to get HTML5 charts in iOS devices.
Have a look at it here - http://blog.fusioncharts.com/2012/02/create-charts-for-iphone-and-ipad-apps-using-fusioncharts-xt/
I decided to use jQuery UI for my autocomplete opposed to a plugin because I read that the plugins are deprecated. My overall goal is to have an autocomplete search bar that hits my database and returns users suggestions of city/state or zipcodes in a fashion similar to google. As of now I am not even sure that the .autocomplete function is being called. I scratched everything I had and decided to start with the basics. I downloaded the most recent version of jQuery UI from http://jqueryui.com/download and am trying to get the example that they use here http://jqueryui.com/demos/autocomplete/ to work. All the scripts that I have included seem to be connected at least linked through Dreamworks so I am fairly certain that the paths I have included are correct. The CSS and Javascripts that I have included are unaltered straight from the download. Below is my HTML code and my backend PHP code that is returning JSon formated data. Please help me. Maybe I need to include a function that deals with the JSon returned data but I am trying to follow the example although I see that they used a local array.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>jQueryUI Demo</title>
<link rel="stylesheet" href="css/ui-lightness/jquery-ui-1.8.17.custom.css" type="text/css" />
<script type="text/javascript" src ="js/jquery-1.7.1.min.js"></script>
<script type="text/javascript" src ="js/jquery-ui-1.8.17.custom.min.js"></script>
</script>
<script type="text/javascript">
$(document).ready(function() {
$("#tags").autocomplete({
source: "search_me.php"
});
});
</script>
</head>
<body>
<div class="demo">
<div class="ui-widget">
<label for="tags">Tags: </label>
<input id="tags" />
</div>
</div><!-- End demo -->
<div class="demo-description">
<p>The Autocomplete widgets provides suggestions while you type into the field. Here the suggestions are tags for programming languages, give "ja" (for Java or JavaScript) a try.</p>
<p>The datasource is a simple JavaScript array, provided to the widget using the source-option.</p>
</div><!-- End demo-description -->
</body>
</html>
Below the PHP part.
<?php
include 'fh.inc.db.php';
$db = mysql_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PASSWORD) or
die ('Unable to connect. Check your connection parameters.');
mysql_select_db(MYSQL_DB, $db) or die(mysql_error($db));
$location = htmlspecialchars(trim($_GET['term'])); //gets the location of the search
$return_arr = array();
if(is_numeric($location)) {
$query = "SELECT
zipcode_id
FROM
user_zipcode
WHERE
zipcode_id REGEXP '^$location'
ORDER BY zipcode_id DESC LIMIT 10";
$result = mysql_query($query, $db) or die(mysql_error($db));
while($row = mysql_fetch_assoc($result)) {
extract($row);
$row_array['zipcode_id'] = $zipcode_id;
array_push($return_arr, $row_array);
}
}
mysql_close($db);
echo json_encode($return_arr);
?>
Thanks for the ideas. Here is an update.
I checked the xhr using firebug and made sure that it is responding thanks for that tip. also the above php code I hadn't initialized $return_arr so i took care of that. Also thanks for the clarification of the js required or rather not required. Now when I type in a zipcode a little box about a centimeter shows up underneath it but I can't see if anything is in there, I would guess not. I went to my php page and set it up to manually set the variable to "9408" and loaded the php page directly through my browser to see what it returned. This is what it returned.
[{"zipcode_id":"94089"},{"zipcode_id":"94088"},{"zipcode_id":"94087"},{"zipcode_id":"94086"},{"zipcode_id":"94085"},{"zipcode_id":"94083"},{"zipcode_id":"94080"}]
I then went to a JSON code validator at this url http://jsonformatter.curiousconcept.com/ at it informed me that my code is in fact returning JSON formatted data. Anymore suggestions to help me troubleshoot the problem would be terrific.
Wow after more research I stumbled across the answer on someone another post.
jquery autocomplete not working with JSON data
Pretty much the JSON returned data must contain Label or Value or both. Switched the zipcode_id to value in my $row_array and... boom goes the dynamite!
Your scripts (js files) references are not correct, should only be:
<!-- the jquery library -->
<script type="text/javascript" src ="js/jquery-1.7.1.min.js"></script>
<!-- the full compressed and minified jquery UI library -->
<script type="text/javascript" src ="js/jquery-ui-1.8.17.custom.min.js"></script>
The files "jquery.ui.core.js", "jquery.ui.widget.js" and "jquery.ui.position.js" are the separated development files, the jquery ui library is splitted into modules.
The file "jquery-ui-1.8.17.custom.min.js" contains them all, compressed and minified !
Concerning the data source, as stated in the "Overview" section of the Autocomplete documentation: when using a an URL, it must return json data, either of the form of:
an simple array of strings: ['string1', 'string2', ...]
or an array of objects with label (and a value - optionnal) property [{ label: "My Value 1", Value: "AA" }, ...]
I'm really not familiar with PHP so just make sure your php script returns one of those :-)