How to: Implement the Camera in C/AL

आलेख
06/05/2016

This example illustrates how you can add access to camera to a specific page from the development environment. Adding a camera option to the Item card, for example, lets you take a picture of a specific item and store it with the item. The example implements three actions; Take Picture, Take Picture High Quality, and Take Picture Low Quality on the Customer Card page, but does not include code that saves the picture to the database. For a Dynamics NAV implementation of this, see Incoming Documents, for example on the Accounting Manager profile, when you use the Dynamics NAV app on a phone.

Important

The camera access is only available on devices that run the Microsoft Dynamics NAV Universal App and have a camera. This means that camera access is not available from the Microsoft Dynamics NAV Windows client or from a browser.

With the following steps, you will create two variables; the CameraAvailable variable is a Boolean that checks whether the current device has a camera. The Camera variable is a DotNet type that gets instantiated by adding code to the OnOpenPage trigger. Then, you will add actions to the Customer Card page that lets the user start the camera and write the code that is run on these actions. And finally, you will add a new trigger Camera::PictureAvailable to handle the incoming picture.

To implement the camera in C/AL

In the development environment, on the Tools menu, choose Object Designer to open the Object Designer window.
In Object Designer, choose Pages, select the Customer Card (page 21) and choose the Design button.
From the Page Designer window, on the View menu, choose C/AL Globals.

Create the following two variables:

Variable name	DataType	SubType
Camera	DotNet	Microsoft.Dynamics.Nav.Client.Capabilities.CameraProvider Important: Choose the Microsoft.Dynamics.Nav.ClientExtensions dll on the Server tab, and then choose Microsoft.Dynamics.Nav.Client.Capabilities.CameraProvider. Make sure to set the properties RunOnClient and WithEvents to Yes.
CameraAvailable	Boolean	-

On the View menu, select C/AL Code and in the C/AL Editor locate the OnOpenPage trigger.

Instantiate the Camera variable by adding the following code to the OnOpenPage trigger

IF Camera.IsAvailable THEN  
BEGIN  
  Camera := Camera.Create;  
  CameraAvailable := TRUE;  
END;

Next, create the page actions. Choose the View menu, and then select Page Actions.
Locate the ActionGroup named Customer and create three actions; TakePicture, TakePictureHigh, and TakePictureLow all of them with the following properties set as shown in the following table.

Property Value

Name TakePicture

Visible CameraAvailable

Promoted Yes

PromotedCategory Process

PromotedIsBig Yes

Image Camera
Next, you will add the code that is executed on the actions. On the TakePicture OnAction trigger, insert the following line of code:
```
Camera.RequestPictureAsync;  
```

Property	Value
Name	TakePicture
Visible	CameraAvailable
Promoted	Yes
PromotedCategory	Process
PromotedIsBig	Yes
Image	Camera

On the TakePictureHigh OnAction trigger, insert the following lines of code:

CameraOptions := CameraOptions.CameraOptions();  
CameraOptions.Quality := 100;  
Camera.RequestPictureAsync(CameraOptions);

On the TakePictureLow OnAction trigger, insert the following lines of code:

CameraOptions := CameraOptions.CameraOptions();  
CameraOptions.Quality := 10;  
Camera.RequestPictureAsync(CameraOptions);

You now need to declare the local variable CameraOptions for the TakePictureHigh and TakePictureLow triggers. From the Page Designer window, on the View menu, choose C/AL Locals.

Create the following variable:

Variable name	DataType	SubType
CameraOptions	DotNet	Microsoft.Dynamics.Nav.Client.Capabilities.CameraOptions Important: Choose the Microsoft.Dynamics.Nav.ClientExtensions dll on the Server tab, and then choose Microsoft.Dynamics.Nav.Client.Capabilities.CameraOptions.

You must now add code to handle the picture for when the camera has captured the picture and the picture has been uploaded to the Microsoft Dynamics NAV Server. In the C/AL Editor, on the PictureAvailable trigger, add code so that the PictureAvailable trigger looks like this.
```
Camera::PictureAvailable(PictureName : Text;PictureFilePath : Text)  
      IncomingFile.OPEN(PictureFilePath);  
      MESSAGE('Picture size: %1', IncomingFile.LEN);  
      IncomingFile.CLOSE;  
      FILE.ERASE(PictureFilePath);  
```
The PictureName contains the name of the file including its extension on the device. The naming scheme depends on the device platform. The PictureFilePath contains the path to the picture in a temporary folder on the server for the current user.

Important

It is important to clean up by using the FILE.ERASE command to avoid accumulating image files.
Now, you need to declare the local variable IncomingFile used in the PictureAvailable trigger. From the Page Designer window, on the View menu, choose C/AL Locals.
Create the following variable:

Variable name DataType

IncomingFile File
Close the C/AL Editor, and then save and compile the page.

You can now test the modified Customer Card page in the Microsoft Dynamics NAV Universal App from either a tablet or a phone with a camera. To read more about different options that can be set for the camera, see CameraOptions Overview.

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How to: Implement the Camera in C/AL

To implement the camera in C/AL

See Also

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