Xojo for loop how to#

Find out how to start a background thread that runs a function where you can pass arguments to it.

(In my opinion, this is usually the best choice.) Investigate the thread functionality provided by your programming language.

Xojo for loop code#

In most cases, you never notice because your application code does not take very long to run, and control is quickly returned to the runtime’s UI event loop.įor the cases where your application code may take some time, your application’s UI will freeze. This is because the UI event loop is a single thread, and control needs to return to the UI thread to allow the “scrollbar move” events to be handled. You won’t be able to move the scrollbar until after the button press function returns. Let’s say you click that button, and then immediately after you wish to move a scrollbar elsewhere in the UI. Let’s say you have a button that when pressed, calls your application code to upload a file to an FTP server. Your application code runs in functions that are called when something happens (a button is pressed, or a menu option chosen, or a keypress or mouse click).

The architecture of an interactive desktop application with a UI is a language runtime that runs an event loop. It’s very important that while I’m uploading a file in ftp I can continue working with the window.” I’m trying the examples of the site but the screen remains locked until the end of the upload.

I often get this question: “I’m calling the method XYZ and the UI freezes until the method returns.”.įor example: “I’m trying to upload a file in FTP. This behaviour can be changed setting the LoopThroughRecords Property, in combination with the NavigateRecords property.OctoDesktop Application UI Freezes in Function Call (C#, VB.NET, VB6, Xojo, etc.) Otherwhise, if the user is displaying the picture of the last record and invokes the Next record action, then the AXImageCanvas instance will display the first record of the table database. This class also brings methods and capture keyboard events allowing navigation throught the records: first record, last record, next record, previous record even if their ID are not consecutives.īy default the navigation between records works in Loop Cycle mode, so if the user is displaying the picture for the first record and invokes the Previous record action, then it will display the last picture on the table database. In these cases, and in addition of the previously described features, it will take care of the usual CRUD operations getting the picture for the specified record, creating new records, updating the current record or deleting the current displayed record (more on this a bit later). Copy the AXImageCanvas Folder from the Project Browser.ĪXImageCanvas supports the following picture formats:ĪXImageCanvas instances can be used in combination of any of the currently supported database engines (Database Edition):.Open the AXImageCanvas Demo Xojo project.How to use AXImageCanvas in your own projects (Install) If the dropped image comes from a File, then the AXImageCanvas instance will keep a reference to the original FolderItem, so it is possible to do additional operations on it.ĪXImageCanvas supports the Copy, Paste, Cut, Clear (Delete) and Undo actions selected from the app menu or using the equivalent keyboard shortcuts. Of course, the displayed image can be set programmatically, just passing the desired Picture Object (instance).

Xojo for loop plus#

This can be done from any dropped image from inside the app, via a Picture File dropped from the Desktop, or another Picture dropped from another AXImageCanvas control or executing App, plus any copied picture from another app or source.

Xojo for loop license#

You can work with the AXImageCanvas class from the IDE without restrictions when running your own apps in Debug Mode but a license is needed when you’re ready to Build any project containing this class.ĪXImageCanvas greately simplifies the task of displaying a Picture into the containing control area (Width and Height), with the ability to correctly display the image maintaining its original aspect ratio whitout touching the original picture. This Class is available as Standard Edition and Database Edition.

Xojo for loop 64 bits#

The Supercharged Canvas with Database Binding!Ĭanvas based UI control for Desktop Xojo developers (Lite, Desktop, Pro and Pro Plus) both for 32 and 64 Bits deployments on macOS, Windows and Linux.