If you build a simple dragger:
$(document).ready(
function()
{
$('#tomove').draggable(
{
axis: 'x',
drag: function(event, ui)
{
mouseUp();
}
});
}
);
And you try to stop it programmatically:
function mouseUp()
{
if($('#tomove').offset().left > 400)
{
$('#tomove').trigger('mouseup');
}
}
You will get this message in error console:
this.helper is null
Is there any way to fix this? Thanks for your help.
It looks like you're just trying to constrain movement on the draggable element, is this correct? Have you seen this page: http://jqueryui.com/demos/draggable/#constrain-movement
EDIT
How about this instead then: (sample page, does what you're asking - be mindful of the jquery inclusion location)
Also notice I changed the name of the method to be something a little more apropos. This will not stop the user from being able to drag back to the left. I didn't think you wanted to actually stop them if they hit 400 (or whatever other wall).
If you want to do that, you merely $('#element').draggable('destroy')
<html>
<head>
<title>Draggable jQuery-UI Width Block</title>
<script src="jquery-1.4.2.min.js" ></script>
<script src="jquery-ui-1.8.1.custom.min.js" ></script>
</head>
<body>
<div id="tomove" style="width:100px;height:20px;background:silver;">
<span>some text</span>
</div>
<script>
$(document).ready( function() {
$('#tomove').draggable({
axis: 'x',
drag: function(event, ui) {
dragBlock( ui );
}
});
});
function dragBlock( ui ) {
if( ui.position.left > 400 ) {
ui.position.left = '400px';
}
if( ui.position.left < 0 ) {
ui.position.left = '0px';
}
}
</script>
</body>
</html>