无法设置音量，音量控制未转发给系统
Can't set volume, volume control is not forwarded to the system
我尝试使用 Android MediaPlayer 框架来播放 mp3 文件
(see this question).
在我设法让它工作之后，我很快意识到，up/down 数量的事件被 class javafxports.android.KeyEventProcessor 捕获并且永远不会被转发。我试图绕过它，但无济于事。
是否有任何方法可以将事件分派到它不会 被捕获的系统？
感谢和问候，
丹尼尔
虽然我讨厌不断地回答自己的问题，但我在使用 Android API 几个小时后找到了解决方案，并仔细阅读了一些文档等等。
我的解决方案部分基于@josé-pereda 就主题 "javafxports how to call android native Media Player" 给出的答案。
我为任务“volumeUp”、“volumeDown”和“mute[=46”创建了一个界面=]":
public interface NativeVolumeService {
void volumeUp();
void volumeDown();
void mute();
}
然后，根据以下关于如何设置 system volume on Android 的回答，我在 Android 上想出了以下实现：
import java.util.ArrayList;
import java.util.logging.Logger;
import android.content.Context;
import android.media.AudioManager;
import android.view.KeyEvent;
import android.view.View;
import android.view.ViewGroup;
import my.package.platform.NativeVolumeService;
import javafxports.android.FXActivity;
public class NativeVolumeServiceAndroid implements NativeVolumeService {
private static final Logger LOG = Logger.getLogger(NativeVolumeServiceAndroid.class.getName());
private final AudioManager audioManager;
private final int maxVolume;
private int preMuteVolume = 0;
private int currentVolume = 0;
public NativeVolumeServiceAndroid() {
audioManager = (AudioManager) FXActivity.getInstance().getSystemService(Context.AUDIO_SERVICE);
maxVolume = audioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
}
@Override
public void volumeUp() {
LOG.info("dispatch volume up event");
KeyEvent event = new KeyEvent(KeyEvent.ACTION_DOWN, KeyEvent.KEYCODE_VOLUME_UP);
dispatchEvent(event, true, false);
}
@Override
public void volumeDown() {
LOG.info("dispatch volume down event");
KeyEvent event = new KeyEvent(KeyEvent.ACTION_DOWN, KeyEvent.KEYCODE_VOLUME_DOWN);
dispatchEvent(event, false, false);
}
@Override
public void mute() {
LOG.info("dispatch volume mute event");
KeyEvent event = new KeyEvent(KeyEvent.ACTION_DOWN, KeyEvent.KEYCODE_VOLUME_MUTE);
dispatchEvent(event, false, true);
}
private void dispatchEvent(KeyEvent event, boolean up, boolean mute) {
// hardware key events (amongst others) get caught by the JavaFXPorts engine (or better: the Dalvik impl from Oracle)
// to circumvent this, we need to do the volume adjustment the hard way: via the AudioManager
// see: https://developer.android.com/reference/android/media/AudioManager.html
// see:
// reason:
// FXActivity registers a FXDalvikEntity, which etends the surface view and passing a key processor
// called KeyEventProcessor - this one catches all key events and matches them to JavaFX representations.
// Unfortunately, we cannot bypass this, so we need the AudioManager
currentVolume = audioManager.getStreamVolume(AudioManager.STREAM_MUSIC);
if (mute) {
if (currentVolume > 0) {
preMuteVolume = currentVolume;
audioManager.adjustStreamVolume(AudioManager.STREAM_MUSIC, AudioManager.ADJUST_SAME,
AudioManager.FLAG_REMOVE_SOUND_AND_VIBRATE | AudioManager.FLAG_SHOW_UI);
} else {
preMuteVolume = 0;
audioManager.adjustStreamVolume(AudioManager.STREAM_MUSIC, preMuteVolume, AudioManager.FLAG_SHOW_UI);
}
} else if (up) {
audioManager.adjustStreamVolume(AudioManager.STREAM_MUSIC,
(currentVolume + 1) <= maxVolume ? AudioManager.ADJUST_RAISE : AudioManager.ADJUST_SAME, AudioManager.FLAG_SHOW_UI);
} else if (!up) {
audioManager.adjustStreamVolume(AudioManager.STREAM_MUSIC,
(currentVolume - 1) >= 0 ? AudioManager.ADJUST_LOWER : AudioManager.ADJUST_SAME, AudioManager.FLAG_SHOW_UI);
}
}
}
为了集成它，我在我的主 class 中创建了适当的实例（我需要这个全局 - 你会看到，为什么）
private void instantiateNativeVolumeService() {
String serviceName = NativeVolumeService.class.getName();
if (Platform.isDesktop()) {
serviceName += "Desktop";
} else if (Platform.isAndroid()) {
serviceName += "Android";
}
try {
volumeService = (NativeVolumeService) Class.forName(serviceName).newInstance();
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException e) {
LOG.log(Level.SEVERE, "Could not get an instance of NativeAudioService for platform " + Platform.getCurrent(), e);
}
}
volumeService 是一个 class 变量。
然后我在我的 Stage 上注册了一个事件处理程序 Scene:
@Override
public void start(Stage stage) throws Exception {
// initiate everything
scene.addEventFilter(KeyEvent.ANY, this::handleGlobalKeyEvents);
// do more stuff, if needed
}
最后，方法 handleGlobalKeyEvents 如下所示：
private void handleGlobalKeyEvents(KeyEvent event) {
// use a more specific key event type like
// --> KeyEvent.KEY_RELEASED == event.getEventType()
// --> KeyEvent.KEY_PRESSED == event.getEventType()
// without it, we would react on both events, thus doing one operation too much
if (event.getCode().equals(KeyCode.VOLUME_UP) && KeyEvent.KEY_PRESSED == event.getEventType()) {
if (volumeService != null) {
volumeService.volumeUp();
event.consume();
}
}
if (event.getCode().equals(KeyCode.VOLUME_DOWN) && KeyEvent.KEY_PRESSED == event.getEventType()) {
if (volumeService != null) {
volumeService.volumeDown();
event.consume();
}
}
}
最后，解决方案是最干净的，也不太复杂。只是直到它起作用的方式有点令人讨厌。
@JoséPereda：如果您想将此解决方案集成为 charm down 插件左右，请随意，但如果您愿意，能被提及和通知会很高兴。
此致，
丹尼尔
我尝试使用 Android MediaPlayer 框架来播放 mp3 文件
(see this question).
在我设法让它工作之后，我很快意识到，up/down 数量的事件被 class javafxports.android.KeyEventProcessor 捕获并且永远不会被转发。我试图绕过它，但无济于事。
是否有任何方法可以将事件分派到它不会 被捕获的系统？
感谢和问候， 丹尼尔
虽然我讨厌不断地回答自己的问题，但我在使用 Android API 几个小时后找到了解决方案，并仔细阅读了一些文档等等。
我的解决方案部分基于@josé-pereda 就主题 "javafxports how to call android native Media Player" 给出的答案。
我为任务“volumeUp”、“volumeDown”和“mute[=46”创建了一个界面=]":
public interface NativeVolumeService {
void volumeUp();
void volumeDown();
void mute();
}
然后，根据以下关于如何设置 system volume on Android 的回答，我在 Android 上想出了以下实现：
import java.util.ArrayList;
import java.util.logging.Logger;
import android.content.Context;
import android.media.AudioManager;
import android.view.KeyEvent;
import android.view.View;
import android.view.ViewGroup;
import my.package.platform.NativeVolumeService;
import javafxports.android.FXActivity;
public class NativeVolumeServiceAndroid implements NativeVolumeService {
private static final Logger LOG = Logger.getLogger(NativeVolumeServiceAndroid.class.getName());
private final AudioManager audioManager;
private final int maxVolume;
private int preMuteVolume = 0;
private int currentVolume = 0;
public NativeVolumeServiceAndroid() {
audioManager = (AudioManager) FXActivity.getInstance().getSystemService(Context.AUDIO_SERVICE);
maxVolume = audioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
}
@Override
public void volumeUp() {
LOG.info("dispatch volume up event");
KeyEvent event = new KeyEvent(KeyEvent.ACTION_DOWN, KeyEvent.KEYCODE_VOLUME_UP);
dispatchEvent(event, true, false);
}
@Override
public void volumeDown() {
LOG.info("dispatch volume down event");
KeyEvent event = new KeyEvent(KeyEvent.ACTION_DOWN, KeyEvent.KEYCODE_VOLUME_DOWN);
dispatchEvent(event, false, false);
}
@Override
public void mute() {
LOG.info("dispatch volume mute event");
KeyEvent event = new KeyEvent(KeyEvent.ACTION_DOWN, KeyEvent.KEYCODE_VOLUME_MUTE);
dispatchEvent(event, false, true);
}
private void dispatchEvent(KeyEvent event, boolean up, boolean mute) {
// hardware key events (amongst others) get caught by the JavaFXPorts engine (or better: the Dalvik impl from Oracle)
// to circumvent this, we need to do the volume adjustment the hard way: via the AudioManager
// see: https://developer.android.com/reference/android/media/AudioManager.html
// see:
// reason:
// FXActivity registers a FXDalvikEntity, which etends the surface view and passing a key processor
// called KeyEventProcessor - this one catches all key events and matches them to JavaFX representations.
// Unfortunately, we cannot bypass this, so we need the AudioManager
currentVolume = audioManager.getStreamVolume(AudioManager.STREAM_MUSIC);
if (mute) {
if (currentVolume > 0) {
preMuteVolume = currentVolume;
audioManager.adjustStreamVolume(AudioManager.STREAM_MUSIC, AudioManager.ADJUST_SAME,
AudioManager.FLAG_REMOVE_SOUND_AND_VIBRATE | AudioManager.FLAG_SHOW_UI);
} else {
preMuteVolume = 0;
audioManager.adjustStreamVolume(AudioManager.STREAM_MUSIC, preMuteVolume, AudioManager.FLAG_SHOW_UI);
}
} else if (up) {
audioManager.adjustStreamVolume(AudioManager.STREAM_MUSIC,
(currentVolume + 1) <= maxVolume ? AudioManager.ADJUST_RAISE : AudioManager.ADJUST_SAME, AudioManager.FLAG_SHOW_UI);
} else if (!up) {
audioManager.adjustStreamVolume(AudioManager.STREAM_MUSIC,
(currentVolume - 1) >= 0 ? AudioManager.ADJUST_LOWER : AudioManager.ADJUST_SAME, AudioManager.FLAG_SHOW_UI);
}
}
}
为了集成它，我在我的主 class 中创建了适当的实例（我需要这个全局 - 你会看到，为什么）
private void instantiateNativeVolumeService() {
String serviceName = NativeVolumeService.class.getName();
if (Platform.isDesktop()) {
serviceName += "Desktop";
} else if (Platform.isAndroid()) {
serviceName += "Android";
}
try {
volumeService = (NativeVolumeService) Class.forName(serviceName).newInstance();
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException e) {
LOG.log(Level.SEVERE, "Could not get an instance of NativeAudioService for platform " + Platform.getCurrent(), e);
}
}
volumeService 是一个 class 变量。
然后我在我的 Stage 上注册了一个事件处理程序 Scene:
@Override
public void start(Stage stage) throws Exception {
// initiate everything
scene.addEventFilter(KeyEvent.ANY, this::handleGlobalKeyEvents);
// do more stuff, if needed
}
最后，方法 handleGlobalKeyEvents 如下所示：
private void handleGlobalKeyEvents(KeyEvent event) {
// use a more specific key event type like
// --> KeyEvent.KEY_RELEASED == event.getEventType()
// --> KeyEvent.KEY_PRESSED == event.getEventType()
// without it, we would react on both events, thus doing one operation too much
if (event.getCode().equals(KeyCode.VOLUME_UP) && KeyEvent.KEY_PRESSED == event.getEventType()) {
if (volumeService != null) {
volumeService.volumeUp();
event.consume();
}
}
if (event.getCode().equals(KeyCode.VOLUME_DOWN) && KeyEvent.KEY_PRESSED == event.getEventType()) {
if (volumeService != null) {
volumeService.volumeDown();
event.consume();
}
}
}
最后，解决方案是最干净的，也不太复杂。只是直到它起作用的方式有点令人讨厌。
@JoséPereda：如果您想将此解决方案集成为 charm down 插件左右，请随意，但如果您愿意，能被提及和通知会很高兴。
此致， 丹尼尔