1 /*
2  * Copyright 2021 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package androidx.camera.camera2.pipe.graph
18 
19 import androidx.camera.camera2.pipe.CameraGraph
20 import androidx.camera.camera2.pipe.GraphState.GraphStateError
21 
22 @JvmDefaultWithCompatibility
23 public interface GraphListener {
24     /**
25      * Used to indicate that the graph is starting. This is called immediately when a [CameraGraph]
26      * is being started.
27      */
onGraphStartingnull28     public fun onGraphStarting() {}
29 
30     /**
31      * Used to indicate that the graph has been initialized and is ready to actively process
32      * requests using the provided [GraphRequestProcessor] interface.
33      */
onGraphStartednull34     public fun onGraphStarted(requestProcessor: GraphRequestProcessor)
35 
36     /**
37      * Used to indicate that the graph is stopping. This is called immediately when a [CameraGraph]
38      * is being stopped.
39      */
40     public fun onGraphStopping() {}
41 
42     /**
43      * Used to indicate that a previously initialized [GraphRequestProcessor] is no longer
44      * available.
45      */
onGraphStoppednull46     public fun onGraphStopped(requestProcessor: GraphRequestProcessor?)
47 
48     /**
49      * Used to indicate that the internal state of the [GraphRequestProcessor] has changed. This is
50      * a signal that previously queued requests may now succeed if they previously failed.
51      */
52     public fun onGraphModified(requestProcessor: GraphRequestProcessor)
53 
54     /** Used to indicate that the graph has encountered an error. */
55     public fun onGraphError(graphStateError: GraphStateError)
56 }
57