1/*
2 * Copyright (C) 2011 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
17package androidx.media.filterpacks.base;
18
19import android.os.Handler;
20import android.os.Looper;
21
22import androidx.media.filterfw.*;
23
24public final class ValueTarget extends Filter {
25
26    public static interface ValueListener {
27        public void onReceivedValue(Object value);
28    }
29
30    private ValueListener mListener = null;
31    private Handler mHandler = null;
32
33    public ValueTarget(MffContext context, String name) {
34        super(context, name);
35    }
36
37    public void setListener(ValueListener listener, boolean onCallerThread) {
38        if (isRunning()) {
39            throw new IllegalStateException("Attempting to bind filter to callback while it is "
40                + "running!");
41        }
42        mListener = listener;
43        if (onCallerThread) {
44            if (Looper.myLooper() == null) {
45                throw new IllegalArgumentException("Attempting to set callback on thread which "
46                    + "has no looper!");
47            }
48            mHandler = new Handler();
49        }
50    }
51
52    @Override
53    public Signature getSignature() {
54        return new Signature()
55            .addInputPort("value", Signature.PORT_REQUIRED, FrameType.single())
56            .disallowOtherPorts();
57    }
58
59    @Override
60    protected void onProcess() {
61        FrameValue valueFrame = getConnectedInputPort("value").pullFrame().asFrameValue();
62        if (mListener != null) {
63            if (mHandler != null) {
64                postValueToUiThread(valueFrame.getValue());
65            } else {
66                mListener.onReceivedValue(valueFrame.getValue());
67            }
68        }
69    }
70
71    private void postValueToUiThread(final Object value) {
72        mHandler.post(new Runnable() {
73            @Override
74            public void run() {
75                mListener.onReceivedValue(value);
76            }
77        });
78    }
79
80}
81
82