This page has been superseded by Files in the Android phone, iPhone & iPad volume.

Android phone & iPhone

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At a glance: This describes the files on an Android phone and an iPhone.

The XSF file

The application reads and writes one kind of file; referred to as XSF files. Such a file contains all the information the application has at the time it was written. The application works on only one cross-section at a time. Thus there is only one cross-section per file.

These XSF files are compatible with the xsec application on other platforms; specifically Apple OS-X and Microsoft Windows. Nevertheless this Android phone xsec or iPhone xsec can be completely stand-alone: its use does not require a computer with or without xsec.

TXT files

The application also writes various text files that present various reports, not intended to be read by the application. These can be viewed and manipulated by any text editor application such as Apple Pages or Microsoft Word.

File structure

The XSF files and the TXT files are text files limited to ASCII characters 10, 13 and 32 to 126 (decimal representation). The file name extension is “xsf” and “txt” respectfully.

The XSF files are intended to be read only by this application, although being text files they can be inspected, and possibly changed in any text editor application. There is one item of information on each line and lines are separated by characters 10 and 13.

New File

A tap on the add + button in the top right corner of the main files tab leads to a display of the measurement system alternatives. This display also has a segmented control offering either “Create example” or “Create blank”. This should be set before a measurement system is selected.
A tap on a measurement system selects that system and the display changes back to the file list with provision for a new file name at the top. At the same time if the segmented control is set to “Create example” the newly created file is populated with a simple example.

.The alternatives offered are:

  • The inch pound system sometimes also called customary units. The maximum dimension is 320 inches or 26’ 8” and the resolution is 0.01 inch.
  • Metric units with large dimensions. The maximum dimension is 32 metres and the resolution is 1 mm.
  • Metric units with small dimensions. The maximum dimension is 3.200 metres and the resolution is 0.1 mm.

At any particular time the application works wholly with one system and there are no facilities for converting data from one system to another.

The need for these alternatives is explained in the General volume under “Geometric data measurement systems”.

At the top of the file list that reappears when a measurement system is selected is a prompt “Enter the new file name” in grey text on a white background. Also an “Ok” button appears to the right of that prompt. A tap on that grey text will cause a virtual keyboard to appear at the bottom of the display. A name is required as described under File names.

File names

The XSF files names generated in the application are limited to six characters and only uppercase letters and numerical digits. A standard virtual keyboard appears when such a name is required. The name of an XSF file imported from a computer is not subject to these restrictions.

Each TXT file is automatically assigned a name. It is the XSF file name followed by the underline character, a letter and one or more numerical digits. The letter indicates which part of the application wrote the file and the numerical digits ensure each file has a unique name. The letters are:

M        a material description.

S          a shape component description.

P          a point component description.

L          a loadcase description, usually including a computation result.

T          a time affect set.

G         errors found in a geometry check.

R         the transformed section properties.

The Files main tab

The files are listed on the Files tab; one of the main tabs described in the Android phone & iPhone –  Introduction under Lists of Entities.

Unlike the other list of entities tabs this has a “< back” button in the top left corner that leads to the “About xsec” display.

Below the list of file names is provision for a note indicating which file is open and below that are buttons labeled “Save” and “Save as”.

The Save button can have a purpose when the open XSF file is to be copied to a computer, and when the application is to be closed.

The Save as button saves the open XSF file under a different name. This does not provide facilities for choosing a directory or a folder. Only one directory is available.

Other files

The other files facilities allow individual materials and components to be copied into the open file from other XSF files in the sandbox. These facilities are not on the main files tab: there is a button on the Materials tab and a button on the Components tab. Each of these invokes a display that has a list of files similar to the list on the main Files tab but headed ‘Import source’.

A tap on a file name will select that file and a note saying it is selected will appear below the list. Also a next > button will appear in the top right corner.

That next button leads to lists of materials or components that can be imported.

A material can be written over an existing material of the same name. The next button leads to the display of a list of materials that can be overwritten, and that display has a next button that leads to a display of a list of other materials that can be imported.

With an written-over material any existing associations with components are maintained.

The other materials can be imported only if there is room for that material. The number of materials is limited to ten.

A component can not be overwritten. There is only one list of components being those that can be imported.

A component can be imported only if:

  • There is not already a component of the same name.
  • There is room for that component. The number of components is limited to ten.

If a component to be imported has an associated material then:

  • If that material has the same name as a existing material then that imported component is associated with that existing material.
  • If, on the other hand, there is no existing material of the same name that material is also imported. The number of materials is limited to ten. If there is no room for that material then the components is not imported.

Connection to a computer


The transfer of files between the phone and a computer:
● Allows the xsf files of worked examples to be transmitted to the phone
● Allows the reports in the txt files written by the application to be transmitted to a computer where they can be included in reports for building officials.
● Allows the advantages of the compatibility of the xsf files with the xsec application on other platforms.
There are differences between an Android phone and an iPhone in this transfer of files.

Android phone connection (Android phone only)

With some Android phone devices it is not possible to transfer files to and from a computer. However with some it is possible.
Described here is the connection between a Samsung Galaxy J250G and a Microsoft Windows 10 computer.
The cable used to charge the battery of the phone has a USB connector. This is used to connect the phone to a USB connector on the computer. If the computer is running at the time this connection is made a Files Explorer window for the phone device will appear on the computer screen. Also at the same time a dialog will appear on the phone posing the question “Allow access to phone data?” with “Deny” and “Allow” buttons.
A tap on the “Allow” button will cause the dialog to disappear and a sub-folder labelled “Phone” to appear on the computer.
On the computer navigate: Phone > Android > data > com.xsec > files This should lead to a Files Explorer display of the files that appear on the applications files display. The various Windows Files Explorer facilities can then be used to copy files into and out of that display.

Apple iPhone connection (iPhone only)

The sandbox (iPhone only)

The files used by the application whose names are displayed in the file list are in what is referred to as the “xsec home documents directory”. This is not accessible to any other applications on the device. In Apple parlance it is in a sandbox.

However these files can be copied to or from a computer that is running iTunes. iTunes, an Apple product is available for both Apple OS-X and Microsoft Windows computers.

These transfers into and out of the iPhone xsec sandbox do not required xsec on the computer.

To transfer files to and from a computer (iPhone only)

iTunes is available to download for free from an Apple web site. The iTunes main menu Help includes an item ‘iPhone user guide’ and that has links to definitive descriptions of this process.

Nevertheless a brief description of the process is:

  1. Download and install iTunes on the computer; either an Apple MacOS or a Microsoft Windows computer.
  2. Connect the iPhone to the computer. The cable for recharging the iPhone battery can be used. This cable is usually connected to the transformer/wall- outlet plug by a standard USB connector. Unplug this from the transformer/wall-outlet plug and plug it into a USB connector on the computer.
  3. On the computer launch iTunes by clicking on the appropriate icon. The iTunes window should appear. In the top left corner of the main part of this window there should be an icon representing the iPhone. This is in the form of a small image of the iPhone.
  4. Click on that iPhone icon.

The display should change to information about the iPhone.

  1. On a sidebar to the left under a heading “Settings” is an item “Apps”. Click on that item.

The main body of the display should change to information about the Apps on the iPhone.

  1. Scroll to the File Sharing section at the bottom of the page. An icon for the xsec application should appear in the left hand part of this display.
  2. Click on that xsec icon.

A list of documents should appear in the right hand part. Although this list is headed “Documents” it should include the XSF files. Files can be dragged to and from this list from and to the directories or folders on the computer.