An Android video editor SDK, in your app and your brand

The SDK is on Maven Central, which Android projects use already. Add it to your app module:

dependencies {
    implementation("dev.nitrakit:nitrakit:0.2.0")
}

Everything is in the dev.nitrakit package; the views are in dev.nitrakit.ui. The SDK asks for no permissions: media reaches it through your picker.

The editor is two Android views. NitrakitPreviewView plays the project and lets the user move and resize layers; NitrakitTimelineView has the timeline, tools and panels. Give both the same Editor and they stay in sync with each other and with your code:

val preview = NitrakitPreviewView(this).apply { this.editor = editor }
val dock = NitrakitTimelineView(this).apply { this.editor = editor }

setContentView(LinearLayout(this).apply {
    orientation = LinearLayout.VERTICAL
    addView(preview, LinearLayout.LayoutParams(MATCH_PARENT, 0, 1f))
    addView(dock, LinearLayout.LayoutParams(MATCH_PARENT, dp(400)))
})

Create the views in code; they don't inflate from XML. They survive backgrounding on their own: the preview keeps its position and the editor keeps its state. When the screen goes away, set their editor to null and close the editor.

The editor never opens the gallery or a file browser itself. When the user taps Add media, it asks your app through onRequest, a suspend function: show your picker, wait, return the result. Return null to use the SDK's built-in picker for fonts, colours, text, text styles and filters.

dock.onRequest = { request ->
    when (request.kind) {
        RequestType.ADD_MEDIA, RequestType.ADD_OVERLAY,
        RequestType.ADD_AUDIO, RequestType.ADD_STICKER -> {
            val file = pickMedia() // your picker, copied to a File
            if (file == null) RequestResponse.Cancel
            else RequestResponse.Source(editor.addMedia(file, id = startUpload(file)).source)
        }
        else -> null // built-in picker
    }
}

Projects refer to media only by your ids. Open a project on a device that doesn't have its files and the SDK asks where each id lives; return a URL, signed if you like, and it downloads it with progress on the clips:

NitrakitMedia.resolve = { id -> MediaLocation.Remote(api.signedUrl(id)) }   // or Local(file)

More in Your pickers and Projects and media.

editor.export renders an MP4 (H.264 video, AAC audio) to the path you give, in the background, while the user keeps editing. Progress and the result arrive on the export thread; job.cancel() stops it and leaves no file behind. Pick the project's size or scale the short side to 720 or 1080 px with exportSettingsFor. See Export.

• Theme: your colours, font and bar sizes, set at runtime so it can follow dark and light mode.
• Tools: hide the ones you don't offer and add your own.
• Wording: rename any label, in your users' languages.

Minifying with R8? Keep the SDK's classes; its native code calls back into them by name:

-keep class dev.nitrakit.** { *; }

Media3 Transformer is Google's library for editing video on Android: trimming, effects and export. It's the right tool if you need a fixed edit, such as trimming a clip before upload. What it doesn't include is the editor your users touch: a timeline, a preview that follows every change, text, undo, pickers and saved projects. That part is most of the work, and it's what Nitrakit gives you, ready to theme.