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public interface Upload
FileItem
and
com.smartgwt.client..MultiFileItem
FormItems that enable users to upload one or more files as a background
operation, without leaving the current page Single file upload: "binary" field type
To use Smart GWT's client-server upload system, you use a DataSource field of 'type'
"binary". By default, a DynamicForm bound to a DataSource with
a field of type "binary" will use the FileItem
, which displays a
standard HTML <input type="upload"> form control.
When you call DynamicForm.saveData()
on a DynamicForm containing a FileItem, Smart GWT processes the
save identically to a saveData() call that did not include a file upload:
FieldType
. Client-side callbacks, such as the callback passed to saveData(), fire normally.
Processing File Uploads with server-side business logic
Server-side business logic that processes file uploads may retrieve upload files via the server side API dsRequest.getUploadedFile(fieldName). The uploaded file is returned as an instance of ISCFileItem, which provides access to a Java InputStream as well as metadata about the file (size, name). See the ${isc.DocUtils.linkForDocNode('javaServerReference', 'Java Server Reference')} for details.
NOTE: request processing engines such as Struts may parse the inbound request
before Smart GWT receives it. If you are creating an RPCManager object inside of a Struts Action and the file being
uploaded is not available via dsRequest.getUploadedFile()
, this is likely to be the problem, and you should
use Smart GWT com.smartgwt.client..DMI
instead.
Server-side validation errors may be provided, including validation errors for the uploaded file (such as too large or invalid content), and will be displayed in the form that attempted an upload.
Be aware of the following special concerns when processing file uploads:
Multi file upload: MultiFileItem
The MultiFileItem provides an interface for a user to save one or more files that are related to a DataSource record, where each file is represented by a record in a related DataSource.
See the com.smartgwt.client..MultiFileItem
docs for details.
Upload without the Smart GWT Server
If it is acceptable that the application will do a full-page reload after the upload completes, you can simply:
encoding
to "multipart" UploadItem
to get a basic HTML upload control action
to a URL where you have deployed server-side code to
handle the upload DynamicForm.submitForm()
to cause the form to be
submitted Note that when you
submitForm(), the only values that will be sent to your actionURL are values for which actual FormItems exist. This
differs from saveData(), in which the entire set of 'form
values'
are always sent. To handle submitting extra values, use HiddenItem
s.
For further details, see the UploadItem
docs.
Background upload without the Smart GWT Server
Achieving background file upload without using the Smart GWT server is also possible although considerably more
advanced. In addition to the steps above, create a hidden <iframe> element in the page, and use target
to target the form submission at this IFRAME. In order
receive a callback notification when the upload completes, after processing the file upload, your server should output
HTML content for the IFRAME that includes a <SCRIPT> block which will navigate out of the IFRAME (generally via
the JavaScript global "top") and call a global method you have declared as a callback.
ListGrid.getAutoFitMaxColumns()
,
ListGrid.getAutoFitMaxColumns()
,
ListGrid.getAutoFitMaxColumns()
,
ListGrid.getAutoFitMaxColumns()
,
ListGrid.getAutoFitMaxColumns()
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