File Manager

Last modified: August 20, 2024

The file manager widget is not supported on native mobile pages.

Introduction

A file manager is used to upload and/or download files.

A file manager must be placed inside a data view connected to the entity that is either a System.FileDocument (or a specialization) or an external entity with a Contents binary attribute.

For an external entity to be used as a file source, it must be defined as a media element in the corresponding OData service. Such an element can be recognized by setting the HasStream attribute to true in its metadata.

When uploading a file through the file manager, the FileDocument object will be committed immediately. When used inside a form, this happens on submission.

A form is submitted just before a microflow or nanoflow is called or when the page is saved.

Properties

An example of file manager properties is represented in the image below:

File manager properties consist of the following sections:

Common
Design Properties
Editability
General
Label
Visibility

Common Section

For more information on properties in this section, see the Common Section section in Properties Common in the Page Editor.

Design Properties Section

The Design Properties allow you to change spacing and alignment of the widget and hide it on phone, tablet, or desktop, if needed. Design properties may vary depending on the type of the widget. For example, for the text widget you can change its font weight, color, alignment, and letter case.

Editability Section

Editability determines whether an end-user can change the value in an input widget.

For more information on properties of this section, see the Editability Section section of Properties Common in the Page Editor.

General Section

Type

The Type property indicates how the end-user will be able to use the file manager.

Value	Description
Upload	The file manager can only be used to upload a file.
Download	The file manager can only be used to download a file.
Both (default)	The file manager can be used to both upload and download a file.

Max File Size (MB)

Max file size (MB) determines the maximum size of files (in megabytes) that can be uploaded.

Default: 5

This value cannot be set arbitrarily high as the platform to which the app is deployed may also impose a limitation on the size of the files that can be uploaded or downloaded.

Allowed Extensions

You can specify file extensions that users are allowed to upload. If no extension is specified, all file extensions are allowed. Separate multiple extensions by a semi-colon, for example, txt;doc

If a file with an extension that is not allowed is selected, a system text for File manager/dynamic image > Error: incorrect file extension will be shown below the file manager.

The feature to allow extensions is not meant as a security feature, as the file manager widget does not check the contents of a file to see if they match the provided extension. For more information, see the Scanning Uploaded Files for Malicious Content section of How to Implement Best Practices for App Security.

Although it is not in the list of approved file extensions, File Manager erroneously allows the .xls extension. This happens when the .xlsx extension is in the accepted list and an .xls file is selected from the All files option. This is due to your operating system’s way of handling the All files option, and it cannot be changed.

Show File in Browser

Show file in browser indicates whether a file will be shown in the browser instead of being downloaded.

Default: False

Label Section

A label describes the purpose of a widget to the end-user.

For more information on properties of this section, see the Label Section section in Properties Common in the Page Editor.

Visibility Section

Visibility determines whether a widget is displayed to the end-user as part of the page.

For more information on properties of this section, see the Visibility Section section in Properties Common in the Page Editor.

Example of File Manager Usage

A file manager needs to be placed in a data view or a snippet that is connected to System.File or is a specialization of it.

For that you can create an entity in your domain model and define that it is a file entity. This is done by the concept of inheritance, sometimes called generalization. By inheriting from System.File your entity gets all the properties of the system file entity.

Do the following:

Open your domain model and create an entity that you would like to define as a file entity.
Double-click the entity to open its properties.
In the Generalization property, click Select.
In the Select Entity dialog box, choose System.File and click the Select button.
Click OK. Your entity now inherits all properties from the System.File entity you selected:
Open a page or a snippet where you would like to place the file manager and add a data view there.
Set the file entity you have created in your domain model as data view’s data source.
Place the file manager inside the data view. You can reference the page example below: