Latest posts from Codename One.
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Insights, release updates, tutorials, and engineering notes from the Codename One team.
Why Codename One Is Moving Beyond Maven Central
Codename One is starting a staged move from Maven Central to a repository we operate on Cloudflare R2. This is not a story about Maven Central being bad. Sonatype runs expensive public infrastructure and has every right to define usage limits or sell a commercial service. Our release shape is simply a bad fit for those limits, and passing that infrastructure bill to Codename One users would make less sense than serving the same signed Maven layout ourselves. ...
A Polyline Is Not a Route
A polyline can draw the points you give it. It cannot discover the road between them. PR #5480 adds com.codename1.maps.routing, a portable route model and service layer for road geometry, distance, duration, waypoints, alternatives, legs, steps, and encoded polylines. We talked about routing in Friday’s release post. The two-line route For the common case, give Routing a map and two coordinates: ...
On-Device AI and MCP on Every Port
There are two very different ways to connect AI to an application. One puts the model inside the feature: OCR a receipt, identify a language, segment a person, or run an application-owned model. The other lets an agent stand outside the application, inspect its semantic UI, and operate it while a developer watches. That second path is extraordinarily useful for debugging. It is also a control channel, so where it listens matters. ...
Health Data Without Fake Certainty
The hardest part of a health API is not reading a heart-rate number. It is knowing what that number means, which store supplied it, whether anything is missing, and what the application is legally allowed to do next. PR #5475 merged a cross-platform health API for HealthKit, Health Connect, recorded workouts, nutrition, Bluetooth health sensors, and deterministic simulation into the core. The implementation has compile, link, and automated coverage. Real-device testing remains important for store permissions and sensor hardware. ...
Push V3: One Message From Your Server to Every Surface
Push notifications should be application infrastructure, not a pile of expiring certificates and provider-specific JSON. This week we merged Push V3 into the Codename One core and completed its new cloud implementation. It gives an application a typed message model, managed provider credentials, subscriptions, server-side segments, campaigns, analytics, and a direct path into Surfaces. There is also one thing every existing push developer should do now: ...
Compact Strings Cut Character Storage in Half
PR #5421 adds compact strings to ParparVM. Strings that fit in Latin-1 now use a byte[]; strings that need wider code units continue to use char[]. ParparVM previously stored every Java String in a char[]. Class names, JSON keys, URLs, numbers, log messages, and much Western European text therefore used two bytes per code unit when one byte was enough. The implementation follows the basic approach in JEP 254 for modern HotSpot. ParparVM also had to preserve fused allocation without adding another pointer to every string. ...
A Lightweight Rich Text Component Without a Web View
PR #5421 adds RichTextComponent, a read-only component for formatted application text. It supports headings, inline styles, lists, links, and images without embedding a web view. A SpanLabel applies one style to wrapped text. A BrowserComponent renders a complete web page. RichTextComponent covers formatted document content between those two cases and participates in ordinary Codename One layout. Rich text inside a scrollable container A common screen mixes formatted text with buttons, images, forms, and other Codename One components inside one scrollable container. A BrowserComponent is a poor fit for that layout because it owns a rectangular native surface and its own page viewport. The browser’s document height does not naturally become the height of a child inside the parent Codename One layout. ...
Pure Codename One Text Editing Without Native Overlays
PR #5386 adds a pure Codename One text-editing path. EditField, RichTextArea, and CodeEditor can now keep their document, selection, and painting inside the lightweight UI while each port supplies keyboard and input-method events. Text input must handle virtual keyboards, hardware keys, autocorrect, dictation, marked text from an input method editor, bidirectional text, selection, clipboard formats, and accessibility geometry. Codename One traditionally delegates that work to a native platform field placed over the lightweight component during editing. The overlay remains the default for TextField and TextArea. It can create a small visual jump, and it cannot participate in lightweight painting for syntax highlights, rich runs, masks, inline images, or a custom selection model. ...
Bluetooth Support Across Every Codename One Target
PR #5399 moves Bluetooth into the Codename One core and adds implementations for every target, including JavaScript. The API covers BLE central and peripheral roles, GATT, L2CAP, classic RFCOMM, simulator fixtures, and native desktop radios. The old Cordova-derived cn1lib handled useful BLE cases on Android and iOS. The new implementation was written for Codename One and exposes the wider protocol surface through capability queries. ...
Calendar API: Local Calendars, Cloud Sync, and Conflict Handling
PR #5413 adds com.codename1.calendar, a cross-platform API for local calendars and cloud providers. It covers events, tasks, recurrence, incremental sync, offline changes, and conflict handling. A request to “add this event to the calendar” often grows into editing, recurrence, provider synchronization, and conflict resolution. The new API handles those requirements through one data model instead of a platform-specific intent. Events, recurrence, and tasks An event can be timed or all-day. It can recur, invite attendees, carry alarms, link a conference, and belong to a provider with its own identifier and version. ...
The Codename One JavaScript Port Is Now Free and Open Source
The Codename One JavaScript port is now open source and available on every plan, including Free. You can also build the JavaScript target locally without a Codename One account. PR #5423 makes our ParparVM-based port the default and moves its source under the same GPLv2 with Classpath Exception license as the rest of Codename One. TeaVM remains available as a fallback. ...
Port Support You Can Trace Back to a Green Test
“Supported on iOS, Android, desktop, and web” sounds useful until you need one method on one target. Does WebSocket work on watchOS? Which Linux architectures do we build? Was the JavaScript media test green this week, or did somebody update a table six months ago and forget it? PR #5389 turns those questions into the Codename One Port Status page. It maps 49 user-facing feature groups across 10 portability targets to current conformance results, environment data, skip reasons, and the date of the run. ...