Android开发笔记（五十八）铃声与震动
拖动条SeekBar
SeekBar继承自进度条ProcessBar，有关ProcessBar的介绍见《Android开发笔记（四十九）异步任务处理AsyncTask》。SeekBar与ProcessBar的不同之处在于，SeekBar是可以拖动的，因此SeekBar可用于媒体播放的进度条，在拖动进度条后，播放器可快进或者快退到指定位置开始播放媒体；SeekBar也可用于调节铃声的音量大小、调节屏幕的亮度、调节字体的大小等等。下面是SeekBar新增加的几个方法与事件：
setThumb : 设置当前进度位置的图标
setThumbOffset : 设置当前进度图标的偏移量
setKeyProgressIncrement : 设置使用方向键更改进度时每次的增加值
拖动条的拖动事件
监听器类名 : OnSeekBarChangeListener
设置监听器的方法 : setOnSeekBarChangeListener
监听器需要重写的方法 :
onProgressChanged : 拖动过程中触发
onStartTrackingTouch : 开始拖动时触发
onStopTrackingTouch : 停止拖动时触发，一般在该方法中加入业务逻辑
铃声管理AudioManager
Android中有六类铃音，分别是：通话音、系统音、来电与收短信的铃声、媒体声（包括音频、视频、游戏等等）、闹钟声、通知声，管理这些铃声音量的工具是AudioManager类。下面是六类铃声的类型说明：
STREAM_VOICE_CALL : 通话音
STREAM_SYSTEM : 系统音
STREAM_RING : 来电与收短信的铃声
STREAM_MUSIC : 媒体声（包括音频、视频、游戏等等）
STREAM_ALARM : 闹钟声
STREAM_NOTIFICATION : 通知声
下面是AudioManager的常用方法：
getStreamMaxVolume : 获取指定类型铃声的最大音量。
getStreamVolume : 获取指定类型铃声的当前音量。
getRingerMode : 获取指定类型铃声的响铃模式。RINGER_MODE_NORMAL表示正常，RINGER_MODE_SILENT表示静音，RINGER_MODE_VIBRATE表示震动
setStreamVolume : 设置指定类型铃声的当前音量。
adjustStreamVolume : 调整指定类型铃声的当前音量。第一个参数是铃声类型；第二个参数是调整方向，ADJUST_RAISE表示调大一级，ADJUST_LOWER表示调小一级，ADJUST_SAME表示保持不变；第三个参数表示调整时的附加动作，一般使用FLAG_PLAY_SOUND表示调整时提示一个铃声。
setRingerMode : 设置指定类型铃声的响铃模式。
震动器Vibrator
Vibrator用于控制手机的振动操作，它的对象需要从系统服务VIBRATOR_SERVICE中获取。震动器的使用比较简单，主要方法如下所示：hasVibrator : 判断设备是否拥有震动器。
vibrate : 震动手机。该方法有多个重载函数，即可设定单次震动的时长，也可设置多次震动的时长，还可设置是否重复震动。
cancel : 取消震动。
震动需要在AndroidManifest.xml中加上如下权限：
<!-- 震动 -->
<uses-permission android:name="android.permission.VIBRATE" />
代码示例
下面是铃声管理即设置音量的代码例子：import com.example.exmring.R;
import android.app.Activity;
import android.content.Context;
import android.media.AudioManager;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageView;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;
public class RingActivity extends Activity implements OnSeekBarChangeListener, OnClickListener {
private static final String TAG = "RingActivity";
private SeekBar sb_voice, sb_system, sb_ring, sb_music, sb_alarm, sb_notify;
private ImageView iv_voice_add, iv_system_add, iv_ring_add, iv_music_add, iv_alarm_add, iv_notify_add;
private ImageView iv_voice_del, iv_system_del, iv_ring_del, iv_music_del, iv_alarm_del, iv_notify_del;
private int[] mStreamType = {
AudioManager.STREAM_VOICE_CALL, AudioManager.STREAM_SYSTEM,
AudioManager.STREAM_RING, AudioManager.STREAM_MUSIC,
AudioManager.STREAM_ALARM, AudioManager.STREAM_NOTIFICATION};
private int[] mMaxVolume = {0, 0, 0, 0, 0, 0};
private int[] mNowVolume = {0, 0, 0, 0, 0, 0};
private SeekBar[] mSeekBar = {
sb_voice, sb_system, sb_ring,
sb_music, sb_alarm, sb_notify};
private int[] mStreamRes = {
R.id.sb_voice, R.id.sb_system, R.id.sb_ring,
R.id.sb_music, R.id.sb_alarm, R.id.sb_notify};
private ImageView[] mAddView = {
iv_voice_add, iv_system_add, iv_ring_add,
iv_music_add, iv_alarm_add, iv_notify_add};
private int[] mAddRes = {
R.id.iv_voice_add, R.id.iv_system_add, R.id.iv_ring_add,
R.id.iv_music_add, R.id.iv_alarm_add, R.id.iv_notify_add};
private ImageView[] mDelView = {
iv_voice_del, iv_system_del, iv_ring_del,
iv_music_del, iv_alarm_del, iv_notify_del};
private int[] mDelRes = {
R.id.iv_voice_del, R.id.iv_system_del, R.id.iv_ring_del,
R.id.iv_music_del, R.id.iv_alarm_del, R.id.iv_notify_del};
private int SEEK_BAR=1, ADD_VIEW=2, DEL_VIEW=3;
private AudioManager mAudioMgr;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_ring);
for (int i=0; i<mStreamType.length; i++) {
mSeekBar[i] = (SeekBar) findViewById(mStreamRes[i]);
mAddView[i] = (ImageView) findViewById(mAddRes[i]);
mDelView[i] = (ImageView) findViewById(mDelRes[i]);
}
setStreamVolume();
for (int i=0; i<mStreamType.length; i++) {
mSeekBar[i].setOnSeekBarChangeListener(this);
mAddView[i].setOnClickListener(this);
mDelView[i].setOnClickListener(this);
}
}
void setStreamVolume() {
mAudioMgr = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
for (int i=0; i<mStreamType.length; i++) {
int type = mStreamType[i];
mMaxVolume[i] = mAudioMgr.getStreamMaxVolume(type);
mNowVolume[i] = mAudioMgr.getStreamVolume(type);
mSeekBar[i].setProgress(100 * mNowVolume[i]/mMaxVolume[i]);
}
}
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
Log.d(TAG, "当前进度为："+seekBar.getProgress()+", 最大进度为"+seekBar.getMax());
int index = getArrayIndex(seekBar.getId(), SEEK_BAR);
int type = mStreamType[index];
int volume = mMaxVolume[index] * seekBar.getProgress()/seekBar.getMax();
Log.d(TAG, "volume="+volume+", last volume="+mNowVolume[index]+", max volume="+mMaxVolume[index]);
if (volume != mNowVolume[index]) {
mNowVolume[index] = volume;
seekBar.setProgress(100 * mNowVolume[index]/mMaxVolume[index]);
}
mAudioMgr.setStreamVolume(type, volume, AudioManager.FLAG_PLAY_SOUND);
}
@Override
public void onClick(View v) {
int add_index = getArrayIndex(v.getId(), ADD_VIEW);
int del_index = getArrayIndex(v.getId(), DEL_VIEW);
if (add_index != -1) {
SeekBar seekBar = mSeekBar[add_index];
if (mNowVolume[add_index] < mMaxVolume[add_index]) {
mNowVolume[add_index] = mNowVolume[add_index]+1;
seekBar.setProgress(100 * mNowVolume[add_index]/mMaxVolume[add_index]);
mAudioMgr.adjustStreamVolume(mStreamType[add_index], AudioManager.ADJUST_RAISE, AudioManager.FLAG_PLAY_SOUND);
}
} else if (del_index != -1) {
SeekBar seekBar = mSeekBar[del_index];
if (mNowVolume[del_index] > 0) {
mNowVolume[del_index] = mNowVolume[del_index]-1;
seekBar.setProgress(100 * mNowVolume[del_index]/mMaxVolume[del_index]);
mAudioMgr.adjustStreamVolume(mStreamType[del_index], AudioManager.ADJUST_LOWER, AudioManager.FLAG_PLAY_SOUND);
}
}
}
private int getArrayIndex(int resid, int type) {
int index = -1;
if (type == SEEK_BAR) {
for (int i=0; i<mSeekBar.length; i++) {
if (mSeekBar[i].getId() == resid) {
index = i;
break;
}
}
} else if (type == ADD_VIEW) {
for (int i=0; i<mAddView.length; i++) {
if (mAddView[i].getId() == resid) {
index = i;
break;
}
}
} else if (type == DEL_VIEW) {
for (int i=0; i<mDelView.length; i++) {
if (mDelView[i].getId() == resid) {
index = i;
break;
}
}
}
return index;
}
}
下面是设备震动的代码例子：
import com.example.exmring.R;
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.os.Vibrator;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.CompoundButton.OnCheckedChangeListener;
import android.widget.EditText;
import android.widget.Toast;
public class ShakeActivity extends Activity implements OnCheckedChangeListener, OnClickListener {
private static final String TAG = "ShakeActivity";
private EditText et_duration;
private CheckBox ck_repeat;
private Button btn_begin, btn_end;
private Vibrator mVibrator;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_shake);
et_duration = (EditText) findViewById(R.id.et_duration);
ck_repeat = (CheckBox) findViewById(R.id.ck_repeat);
btn_begin = (Button) findViewById(R.id.btn_begin);
btn_end = (Button) findViewById(R.id.btn_end);
ck_repeat.setOnCheckedChangeListener(this);
btn_begin.setOnClickListener(this);
btn_end.setOnClickListener(this);
mVibrator = (Vibrator) getSystemService(Context.VIBRATOR_SERVICE);
}
@Override
public void onClick(View v) {
if (v.getId() == R.id.btn_begin) {
if (mVibrator.hasVibrator() != true) {
Toast.makeText(this, "当前设备未找到震动器", Toast.LENGTH_LONG).show();
} else {
long duration = Integer.parseInt(et_duration.getText().toString());
if (ck_repeat.isChecked() != true) {
mVibrator.vibrate(duration);
} else {
long[] pattern = {duration, duration};
mVibrator.vibrate(pattern, 0);
}
}
} else if (v.getId() == R.id.btn_end) {
mVibrator.cancel();
}
}
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
}
}
点此查看Android开发笔记的完整目录