The page I am working on has a javascript function executed to print parts of the page. For some reason, printing in Safari, causes the window to somehow update. I say somehow, because it does not really refresh as in reload the page, but rather it starts the "rendering" of the page from start, i.e. scroll to top, flash animations start from 0, and so forth. The effect is reproduced by this fiddle: http://jsfiddle.net/fYmnB/ Clicking the print button and finishing or cancelling a print in Safari causes the screen to "go white" for a sec, which in my real website manifests itself as something "like" a reload. While running print button with, let's say, Firefox, just opens and closes the print dialogue without affecting the fiddle page in any way. Is there something with my way of calling the browsers print method that causes this, or how can it be explained - and preferably, avoided? P.S.: On my real site the same occurs with Chrome. In the ex
Tiddlywiki has several methods of saving data, depending on which browser is used.
ReplyDeleteIf ActiveX is enabled, it uses Scripting.FileSystemObject.
On Gecko-based browsers, it tries to use UniversalXPConnect.
If Java is enabled, it uses the TiddlySaver Java applet.
If Java LiveConnect is enabled, it tries to use Java's file classes.
HTML5's File[1], FileWriter[2], and FileSystem[3] APIs are available in the latest Developer channel of Google Chrome. The FileSystem API lets you read/write to a sandbox filesystem within a space the browser knows about. You cannot, for example, open 'My Pictures' folder on the user's local FS and read/write to that. That's something in the works, but it won't be ready for a while. Example of writing a file:
ReplyDeletewindow.requestFileSystem(
TEMPORARY, // persistent vs. temporary storage
1024 * 1024, // 1MB. Size (bytes) of needed space
initFs, // success callback
opt_errorHandler // opt. error callback, denial of access
);
function initFs(fs) {
fs.root.getFile('logFile.txt', {create: true}, function(fileEntry) {
fileEntry.createWriter(function(writer) { // FileWriter
writer.onwrite = function(e) {
console.log('Write completed.');
};
writer.onerror = function(e) {
console.log('Write failed: ' + e.toString());
};
var bb = new BlobBuilder();
bb.append('Lorem ipsum');
writer.write(bb.getBlob('text/plain'));
}, errorHandler);
}
}
Check out this HTML5 Storage slide deck for more code snippets.
It uses a java file references like this:
ReplyDeletedrivers.tiddlySaver = {
name: "tiddlySaver",
deferredInit: function() {
if(!document.applets["TiddlySaver"] && !$.browser.mozilla && !$.browser.msie && document.location.toString().substr(0,5) == "file:") {
$(document.body).append("<applet style='position:absolute;left:-1px' name='TiddlySaver' code='TiddlySaver.class' archive='TiddlySaver.jar' width='1'height='1'></applet>");
}
},
isAvailable: function() {
return !!document.applets["TiddlySaver"];
},
loadFile: function(filePath) {
var r;
try {
if(document.applets["TiddlySaver"]) {
r = document.applets["TiddlySaver"].loadFile(javaUrlToFilename(filePath),"UTF-8");
return (r === undefined || r === null) ? null : String(r);
}
} catch(ex) {
}
return null;
},
saveFile: function(filePath,content) {
try {
if(document.applets["TiddlySaver"])
return document.applets["TiddlySaver"].saveFile(javaUrlToFilename(filePath),"UTF-8",content);
} catch(ex) {
}
return null;
}
}
The answer is in the future, it will. See http://www.w3.org/TR/FileAPI/.
ReplyDeleteWith Firefox 3.6.8 see http://www.html5rocks.com/tutorials/file/dndfiles/ for samples with source code.
Technically you can do
ReplyDeletenetscape.security.PrivilegeManager.enablePrivilege('UniversalBrowserWrite');
in a netscape-compatible browser (Firefox, Mozilla, Netscape), and it will ask the user* whether or not to allow filesystem access, but this is not portable.
*once per browser process
The answer is indeed NO. Java applets, and the dreaded ActiveX plugins are usually used if this is required
ReplyDeleteCan javascript access a filesystem?
ReplyDeleteNot outside of the sandbox area mentioned above, to the best of my knowledge. However, it can access a signed java applet that has callable public methods which can get to all files. I have done it and it works fine and is cross browser.
The signing part is somewhat involved and for professional use you might need to pay for a code signing certificate which authorises your identity. Get it from some place like Verisign. That way users at least know who the applet is written by (if that helps). You can sign it yourself for free but one of those "possible security risk" popups will occur at first use for authorisation by the user.
You would think that such signed applets for file writing would exist already for download but I couldn't find any via searching. If they did, you could just plug it in your page, learn the API and off you go.