func (m *mainLoop) loop(init chan<- struct{}) {
runtime.LockOSThread()
defer runtime.UnlockOSThread()
looper := C.ALooper_prepare(C.ALOOPER_PREPARE_ALLOW_NON_CALLBACKS)
if looper == nil {
panic("ALooper_prepare returned nil")
}
m.looper = looper
init <- struct{}{}
for {
select {
case <-m.quit:
if m.renderState != nil && m.renderState.ctx != egl.Context(unsafe.Pointer(nil)) {
if !egl.MakeCurrent(m.renderState.disp, egl.Surface(unsafe.Pointer(nil)), egl.Surface(unsafe.Pointer(nil)), egl.Context(unsafe.Pointer(nil))) {
panic("Error: eglMakeCurrent() failed\n")
}
}
m.ack <- struct{}{}
break
case <-m.resume:
m.running = true
m.ack <- struct{}{}
case <-m.pause:
m.running = false
m.width, m.height = 0, 0
m.ack <- struct{}{}
case m.focused = <-m.focus:
m.width, m.height = 0, 0
m.ack <- struct{}{}
case m.renderState = <-m.render:
m.ack <- struct{}{}
case inputQ := <-m.input:
if inputQ != nil {
C.AInputQueue_attachLooper(inputQ, m.looper, LOOPER_ID_INPUT, nil, nil)
} else {
C.AInputQueue_detachLooper(m.inputQ)
}
m.inputQ = inputQ
m.ack <- struct{}{}
default:
m.frame()
}
}
}
// The loop handles native input events.
func androidEventLoopFunc(event chan interface{}, looperCh chan *C.ALooper) loop.LoopFunc {
return func(l loop.Loop) error {
var inputQueue *C.AInputQueue
runtime.LockOSThread()
defer runtime.UnlockOSThread()
looper := C.ALooper_prepare(C.ALOOPER_PREPARE_ALLOW_NON_CALLBACKS)
if looper == nil {
Fatalf("ALooper_prepare returned nil")
}
looperCh <- looper
for {
select {
case untypedEvent := <-event:
switch event := untypedEvent.(type) {
case inputQueueCreatedEvent:
inputQueue = (*C.AInputQueue)(event.inputQueue)
C.AInputQueue_attachLooper(inputQueue, looper, LOOPER_ID_INPUT, nil, nil)
case inputQueueDestroyedEvent:
inputQueue = (*C.AInputQueue)(event.inputQueue)
C.AInputQueue_detachLooper(inputQueue)
}
default:
if inputQueue != nil {
ident := C.ALooper_pollAll(-1, nil, nil, nil)
switch ident {
case LOOPER_ID_INPUT:
processInput(inputQueue)
case C.ALOOPER_POLL_ERROR:
Fatalf("ALooper_pollAll returned ALOOPER_POLL_ERROR\n")
}
}
}
}
}
}
func runInputQueue(vm, jniEnv, ctx uintptr) error {
env := (*C.JNIEnv)(unsafe.Pointer(jniEnv)) // not a Go heap pointer
// Android loopers select on OS file descriptors, not Go channels, so we
// translate the inputQueue channel to an ALooper_wake call.
l := C.ALooper_prepare(C.ALOOPER_PREPARE_ALLOW_NON_CALLBACKS)
pending := make(chan *C.AInputQueue, 1)
go func() {
for q := range inputQueue {
pending <- q
C.ALooper_wake(l)
}
}()
var q *C.AInputQueue
for {
if C.ALooper_pollAll(-1, nil, nil, nil) == C.ALOOPER_POLL_WAKE {
select {
default:
case p := <-pending:
if q != nil {
processEvents(env, q)
C.AInputQueue_detachLooper(q)
}
q = p
if q != nil {
C.AInputQueue_attachLooper(q, l, 0, nil, nil)
}
inputQueueDone <- struct{}{}
}
}
if q != nil {
processEvents(env, q)
}
}
}