getNextPlatformViewId method
Allocates a unique identifier for a platform view.
A platform view identifier can refer to a platform view that was never created, a platform view that was disposed, or a platform view that is alive.
Typically a platform view identifier is passed to a platform view widget which creates the platform view and manages its lifecycle.
Implementation
int getNextPlatformViewId() {
// On the Android side, the interface exposed to users uses 32-bit integers.
// See https://github.com/flutter/engine/pull/39476 for more details.
// We can safely assume that a Flutter application will not require more
// than MAX_INT32 platform views during its lifetime.
const int MAX_INT32 = 0x7FFFFFFF;
assert(_nextPlatformViewId <= MAX_INT32);
return _nextPlatformViewId++;
}