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Sunday, June 20, 2021PrintSubscribe
Drawing Pad

Taking photos in business apps often requires the visual annotation of the image. Another common scenario is sketching on the pre-defined template. Touch UI provides a built-in drawing pad that works seamlessly with the BLOB fields of your app. The feature is enabled by default and can be activated with a tap on the “Draw” button.


The drawing pad will be immediately displayed in fullscreen mode in response to the tap. It offers several tools: pen, highlighter, blur, and eraser with multiple levels of undo and redo. You can draw with a finger or a stylus compatible with the touch-screen device. Mouse pointers will also work. 

The “pen” and “highlighter” will impact the image as one would expect. The “blur” tool will blur the image contents. The “eraser” will remove the effect of the other tools.


Developers can handle the blobdrawtoolbox.app event triggered on the document and override the available tools and their properties such as the width of the stroke and the color choices. The toolbox property of the event provides access to the default tool configuration.

The drawing is composed of multiple layers. Saving of the drawing will compose the final image that will be submitted to the server when the data record is saved. The end user can perform multiple sessions of drawing prior to the submission since the layers remain preserved until the record has been saved.


Sketching on the template will require a default image to be provided. Create a custom script to handle the getdefaultblob.app event. The field property will indicate the name of the blob field that does not have a value. If e.blob.url or e.blob.icon properties are assigned in the event handler, then the corresponding image will be downloaded or a material icon will be drawn.


For example, the following handler will cause the framework to create a blue material icon for the category picture in the application.


The default image based on an icon may serve as a blob stub whenever the optional image is required. The end user may tap on the image and have it replaced with their by either taking a photo on the device or choosing a previously created image.



Tapping on the default blob image will always activate the drawing pad if the BLOB data field is tagged as image-user-defined-none. The end user will not be able to replace the template image.

The end users may take real-world photos and provide the visual comments with the drawing pad tools. Keep in mind that the huge photographs taken by modern day cameras will likely be redundant for business purposes. Make sure to specify the image-size-WxH tag to engage the image preprocessor to enforce the pre-defined image photo size and graphical annotations. 


Drawing pad provides a powerful tool for the line-of-business apps. Naturally it may not always be desirable to allow image alteration. Tag the blob data field as image-editor-none to disable the drawing pad.


By default the blob images are rendered as thumbnails. Tag the data fields as image-original-always if the original image must be displayed both when the users are viewing and editing the data. The field with the tag image-original-editing will show the original image if the blob is presented in the “edit” mode. End users may still download the original image when viewing the record.


The drawing pad will work on the small devices, tablets, and huge desktop monitors.
Thursday, May 30, 2019PrintSubscribe
VS 2019, Multi File Upload, Command Line Mode
Code On Time release 8.7.11.0 brings support for Visual Studio 2019, Multi-File Upload in Touch UI applications, and new command line options that allow creating apps with automated scripts.

Start using Visual Studio 2019 with your projects. The new development environment is fully integrated in the app generator. If you do have an existing project and want to migrate to the latest tools from Microsoft, then select the app on the start page of the generator and choose Open option. File Explorer will show the project files. Either delete the file with *.sln extension and regenerate your app or right-click the solution file, open it with Visual Studio 2019, select the solution file item in Solution Explorer, and press Ctrl+S.

Multi-file Upload is now available in Touch UI if you add Upload action to a compatible data controller. End users of your app will be able to choose multiple files to upload. The app will create a database record for each file, have the file submitted to the server, and persist it to the first BLOB field.


Command Line support is now available in the app generator.

Enter the following in the command line to generate a database app that works on mobile devices and in the web browser:

codeontime -Generate "c:\apps\myapp3" -DbConnection "Data Source=;Initial Catalog=northwind-cmd;Integrated Security=True;" -run

Build mobile and web database apps in seconds in command line. Use generated apps to validate your ideas, prototype data input forms, enter sample data, and much more. Apps built with Code On Time are metadata-driven. Create you own customization tools to invoke codeontime.exe in command line mode. The upcoming Code On Time v9 will be using command line mode extensively since the entire development environment is incorporated directly in the apps.


The following features and fixes also included in this release:
  • (Model Builder) All words in field labels are capitalized when a model is created.
  • (Touch UI) Optimized packaging of JSON properties of FieldValue object instances to minimize footprint for offline/disconnected logging.
  • (Client Library) Values of static Check Box List are correctly displayed when more than one item is selected.
  • (Framework) Blob adapter configuration is not included in the JSON controller descriptor.
  • (Touch UI) Selection of files in BLOB input will make the input focused.
  • (Framework) New TemporaryFileStream class is used for temporary storage of BLOB content.
  • (Touch UI) Method $app.confim support chained alternative execution of code with promises when confirmation is canceled.
  • (Offline Sync) Concurrent uploading of BLOBs is implemented with optional reconciliation of failed to upload blobs.
  • (Offline Sync) End user can opt to sync without data refresh. The option will remain selected until data refresh is explicitly requested. This makes possible working offline and only uploading changes to the server.
  • (Framework) Batch Editing of many-to-many fields works correctly when the primary key field is explicitly included in the view.
  • (Framework) Batch Editing will not erase values of many-to-many fields that are not selected in the Batch Edit form.
  • (Framework) Surveys accept inline functions and non-string values as "Visible When" and "Read Only When" expressions in questions and topics.
  • (Framework) Signature prompt is vertically aligned to the middle.
  • (Touch UI) Download icon is not displayed anymore next to "DOWNLOAD" button.
  • (Offline Sync) Added support for signatures.
  • (Touch UI) Placing $none in "Notify" property of action will prevent notification from being displayed.
  • (ODP) Completed implementation of thumbnail production on the client.
  • (Model Builder) New implementation of multi-level construction of Copy property of lookups for both 1-to-Many and 1-to-1 relationships.
  • (Classic) Implementation of BLOB uploading is now moved to Offline Data Processor.
  • (Framework) Download cookie is set on the server only when specified in the request.
  • (Framework) Azure Blob Adapter now uses HTTPS by default.
  • (Touch UI) Fixed signature resizing.
  • (Model Builder) "Enter" key in the property of the last field will post changes and re-select the same field property.
  • (Localization) Italian localization contributed by Massimo Ciurleo.
  • (ODP) Signatures in child data views are fully supported in transactional mode (when odp is enabled).
  • (Project Wizard) New "Addons" section in Features.
  • (Framework) Filter expression in the model will not cause errors when advanced search is executed.
  • (Framework) Default transaction scope is "sequence",
  • (Offline Sync) If transaction scope is "sequence" then ODP-assigned sequence is overridden with an offline sequence number. If transaction scope is explicitly set to "all", then the sequence is assigned to 0 for all transactions in the log.
  • (Touch UI) Button "driving directions" correctly composes Google Maps query based on fields tagged as map-latitude and map-longitude.
  • (Client Library)  Failed blob will be abandoned since there is not much that the user can do. The row was either inserted or updated already. The blob was rejected by the server. Abandoning of blob eliminates infinite loop of submission.
  • (Framework) A registration record for on-demand fields with blank "On Demand Handler" is not generated in Blob.generated.cs(vb) to prevent duplicate "empty" handlers when more than one such field is defined.
  • (Classic) Rich Text editor correctly sets the value produced in custom editors.
  • (Classic UI) Data views correctly synchronize with the inserted record.
  • (Touch UI) Forced notifications without text will not cause an empty alert displayed when ui.notification.enabled = false.
  • (Framework) Generated data access object has a unique name to prevent clashing with parameters created from access control rules.
  • (Framework) New property ApplicationServices.DisplayName returns application name. The value is derived either from the default app name or from the value stored in appName property in ~/touch-settings.json.
  • (Framework) Method ApplicationServices.ValidateBlobAccess ensures that user can access the row that contains the BLOB field. The field must also be accessible to the user. Otherwise access to blob is denied.
  • (Touch UI) Context menu options for child data views that were defined in their own containers are not displayed anymore. Use fields of DataView type to display child data instead. Previously visible context options have caused exceptions at runtime.
  • (Framework) Method NodeSetCollection.SetTag correctly sets tags for both data fields and views in both singular and chained calls.
  • (Touch UI) Inline editing in child data views will not cause identity fields to be marked as "Modified" and allow entering rows without errors
  • (Touch UI) Refactored panel opening and closing.
Our next goal is to release Offline Data Processor and Offline Sync in update 8.9.0.0 due out by the end of June 2019. We are skipping 8.8.0.0 release numbering since both features are being released together. Cloud On Time for Android will be out in July 2019. The new roadmap has been prepared and will be unveiled soon!


Wednesday, May 29, 2019PrintSubscribe
Multi File Upload
Code On Time release 8.7.11.0 introduces Multi-File Upload. End users can select multiple files and submit them for upload at once to create multiple database records. Application framework automatically inserts a table row for each file, uploads the file, and persists the data either to the database or to an external storage system.

Here is how it works:

1) Start upload.



2. Select multiple files.


3. Preview the selection and tap Submit.


4. Multiple database records are created for each file and associated with a parent if needed.



The feature is activated when the Upload action is executed by the data controller. A built-in form is displayed to allow selecting multiple files for upload.  User submits the form and the framework starts processing files one by one. For each file an Insert action is executed through the same data controller. By default, the view createForm1 is used to figure a list of data fields for Insert. An alternative view can be specified in Command Argument of Insert action.  Special fields are detected to store File Name, Content Type, and Length of the file. For child data views, the master field values are also included. If insert is successful, then the physical file is uploaded to the server and stored in the first on-demand field of Byte[] type. Failure to insert a record or to upload a file will interrupt the processing. The data view is refreshed when processing of all files has been completed.

Consider the following database schema that allows associating documents with the supplier records.



Table Docs defines three explicit fields to maintain information about the files: FileName, ContentType, and Length. The physical data will be stored outside of the database and processed with File System Blob adapter.

Start Code On Time and create an app with two data models - Suppliers and Docs. Next, start Project Designer and begin defining the new field with the name Data and type Byte[] in Docs controller. Mark the field as On Demand. Enter DocID in Source Fields and DocsData in On Demand Handler. Choose Thumbnail in On Demand Style drop down to have a file preview in the app. Save the new field and drag it to createForm1, editForm1, and grid1 in the Docs controller.



Select Docs data controller and enter the following in the Blob Adapter Config property:

Field: Data
Storage-System: File 
Path-Template: C:\app\DocsFileData\{DocID}-{FileName}
File-Name-Field: FileName
Content-Type-Field: ContentType
Length-Field: Length

Make sure that the specified folder C:\app\DocsFileData does exist on your device. Application will use the primary key of the Docs record and the file name to create physical copies of the files submitted to the virtual on-demand Data field.

Add a new action with command name set to Upload to action group Docs / Actions / ag3 .



Proceed to drag Docs controller onto Suppliers controller or copy Docs and paste onto Suppliers. This will create a new field with type DataView and name Docs in the fields of Suppliers controller. Drag the new field to editForm1 view in the same controller.




Run the application and select a supplier.



Select Upload action and choose multiple files to upload.



Tap submit and see the corresponding records appear in the app.


The entire process take a few seconds. User can choose individual records to add comment. There is also an alternative it to create one record at a time if a more deliberative data input mode is desired.



Multi-file upload significantly improves ease-of-use for document management applications.