1 /*
2  * Copyright (C) 2022 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 package com.android.systemui.smartspace
17 
18 /**
19  * A {@link SmartspacePrecondition} captures the conditions that must be met for Smartspace to be
20  * used in a particular setting.
21  */
22 interface SmartspacePrecondition {
23     /**
24      * A callback for receiving updates when conditions have changed.
25      */
26     interface Listener {
onCriteriaChangednull27         fun onCriteriaChanged()
28     }
29 
30     /**
31      * Adds a listener to receive future updates. {@link Listener#onCriteriaChanged} will be called
32      * immediately upon adding.
33      */
34     fun addListener(listener: Listener)
35 
36     /**
37      * Removes a listener from receiving future updates.
38      */
39     fun removeListener(listener: Listener)
40 
41     /**
42      * Returns whether all conditions have been met.
43      */
44     fun conditionsMet(): Boolean
45 }