我正在关注this 教程，除了没有创建搜索栏和微调器之外，每个东西都正常工作。 这就是我想要的 的java：
public class MainActivity extends AppCompatActivity {
private MediaPlayer mediaPlayer;
private Equalizer equalizer;
private LinearLayout linearLayout;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
setVolumeControlStream(AudioManager.STREAM_MUSIC);
mediaPlayer = MediaPlayer.create(this, R.raw.song);
mediaPlayer.start();
equalizer = new Equalizer(0, mediaPlayer.getAudioSessionId());
equalizer.setEnabled(true);
setUpEqualizer();
mediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mediaPlayer) {
}
});
}
public void setUpEqualizer() {
linearLayout = (LinearLayout) findViewById(R.id.linearlayequ);
TextView equheading = new TextView(this);
equheading.setText("Equalizer");
equheading.setTextSize(20);
equheading.setGravity(Gravity.CENTER_HORIZONTAL);
linearLayout.addView(equheading);
short nofrequencyband = equalizer.getNumberOfBands();
final short lowerfrequencyband = equalizer.getBandLevelRange()[0];
final short upperfrequencyband = equalizer.getBandLevelRange()[1];
for (short i = 0; i < nofrequencyband; i++) {
final short eqbandindex = i;
TextView frheadertv = new TextView(this);
frheadertv.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
frheadertv.setGravity(Gravity.CENTER_HORIZONTAL);
frheadertv.setText((equalizer.getCenterFreq(eqbandindex) / 1000) + "Hz");
linearLayout.addView(frheadertv);
LinearLayout seeklay = new LinearLayout(this);
seeklay.setOrientation(LinearLayout.HORIZONTAL);
TextView lowereqbandlvl = new TextView(this);
lowereqbandlvl.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));
lowereqbandlvl.setText((lowerfrequencyband / 100) + "dB");
TextView highreqbandlvl = new TextView(this);
highreqbandlvl.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));
highreqbandlvl.setText((upperfrequencyband / 100) + "dB");
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
layoutParams.weight = 1;
SeekBar seekBar = new SeekBar(this);
seekBar.setId(i);
seekBar.setLayoutParams(layoutParams);
seekBar.setMax(upperfrequencyband - lowerfrequencyband);
seekBar.setProgress(equalizer.getBandLevel(eqbandindex));
seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int i, boolean b) {
equalizer.setBandLevel(eqbandindex, (short) (i + lowerfrequencyband));
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
});
seeklay.addView(lowereqbandlvl);
seeklay.addView(seekBar);
seeklay.addView(highreqbandlvl);
linearLayout.addView(seeklay);
equalizSound();
}
}
public void equalizSound() {
ArrayList<String> equalizername = new ArrayList<String>();
ArrayAdapter<String> spinnerAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_spinner_dropdown_item);
spinnerAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
Spinner spinner = (Spinner)findViewById(R.id.spinner);
for (short i=0;i<equalizer.getNumberOfPresets();i++){
equalizername.add(equalizer.getPresetName(i));
}
spinner.setAdapter(spinnerAdapter);
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
}
@Override
public void onNothingSelected(AdapterView<?> adapterView) {
}
});
}
@Override
protected void onPause() {
super.onPause();
if (isFinishing() && mediaPlayer != null) {
equalizer.release();
mediaPlayer.release();
mediaPlayer = null;
}
}
}
使用均衡器是否需要任何权限，或者我犯了错误，任何建议都会有所帮助。应用程序不会抛出任何异常，只会播放该歌曲。
答案 0 :(得分：0)
我用它来制作均衡器
public class MainActivity extends AppCompatActivity
implements SeekBar.OnSeekBarChangeListener,
CompoundButton.OnCheckedChangeListener {
TextView bass_boost_label = null;
SeekBar bass_boost = null;
CheckBox enabled = null;
Button flat = null;
Equalizer eq = null;
BassBoost bb = null;
Virtualizer vr = null;
SeekBar virtal = null;
int min_level = 0;
int max_level = 100;
static final int MAX_SLIDERS = 5; // Must match the XML layout
SeekBar sliders[] = new SeekBar[MAX_SLIDERS];
TextView slider_labels[] = new TextView[MAX_SLIDERS];
public static int num_sliders = 0;
private MediaPlayer mediaPlayer;
private ArrayList<String> equalizername = new ArrayList<String>();
private Spinner spinner;
/*=============================================================================
onCreate
=============================================================================*/
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
enabled = (CheckBox) findViewById(R.id.enabled);
enabled.setOnCheckedChangeListener(this);
bass_boost = (SeekBar) findViewById(R.id.bass_boost);
bass_boost.setOnSeekBarChangeListener(this);
bass_boost_label = (TextView) findViewById(R.id.bass_boost_label);
sliders[0] = (SeekBar) findViewById(R.id.slider_1);
slider_labels[0] = (TextView) findViewById(R.id.textView);
sliders[1] = (SeekBar) findViewById(R.id.slider_2);
slider_labels[1] = (TextView) findViewById(R.id.textView2);
sliders[2] = (SeekBar) findViewById(R.id.slider_3);
slider_labels[2] = (TextView) findViewById(R.id.textView3);
sliders[3] = (SeekBar) findViewById(R.id.slider_4);
slider_labels[3] = (TextView) findViewById(R.id.textView4);
sliders[4] = (SeekBar) findViewById(R.id.slider_5);
slider_labels[4] = (TextView) findViewById(R.id.textView5);
virtal = (SeekBar) findViewById(R.id.seekBar2);
mediaPlayer = MediaPlayer.create(this, R.raw.song2);
mediaPlayer.start();
eq = new Equalizer(0, mediaPlayer.getAudioSessionId());
for (short i = 0; i < eq.getNumberOfPresets(); i++) {
equalizername.add(eq.getPresetName(i));
Log.e("name", "" + eq.getPresetName(i));
}
spinner = (Spinner) findViewById(R.id.spinner);
ArrayAdapter arrayAdapter = new ArrayAdapter(this, android.R.layout.simple_spinner_dropdown_item, equalizername);
spinner.setAdapter(arrayAdapter);
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
eq.usePreset((short) i);
updateUI();
}
@Override
public void onNothingSelected(AdapterView<?> adapterView) {
}
});
if (eq != null) {
eq.setEnabled(true);
int num_bands = eq.getNumberOfBands();
Log.e("band", "" + num_bands);
num_sliders = num_bands;
short r[] = eq.getBandLevelRange();
min_level = r[0];
max_level = r[1];
for (int i = 0; i < num_sliders && i < MAX_SLIDERS; i++) {
int[] freq_range = eq.getBandFreqRange((short) i);
sliders[i].setOnSeekBarChangeListener(this);
slider_labels[i].setText(formatBandLabel(freq_range));
}
}
for (int i = num_sliders; i < MAX_SLIDERS; i++) {
sliders[i].setVisibility(View.GONE);
slider_labels[i].setVisibility(View.GONE);
}
bb = new BassBoost(0, mediaPlayer.getAudioSessionId());
if (bb != null) {
} else {
bass_boost.setVisibility(View.GONE);
bass_boost_label.setVisibility(View.GONE);
}
vr = new Virtualizer(0, mediaPlayer.getAudioSessionId());
virtal.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int i, boolean b) {
if (seekBar == virtal) {
vr.setEnabled(level > 0 ? true : false);
vr.setStrength((short) i); // Already in the right range 0-1000
} else if (eq != null) {
int new_level = min_level + (max_level - min_level) * level / 100;
for (int j = 0; j < num_sliders; j++) {
if (sliders[j] == seekBar) {
eq.setBandLevel((short) j, (short) new_level);
break;
}
}
}
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
});
updateUI();
}
/*=============================================================================
onProgressChanged
=============================================================================*/
@Override
public void onProgressChanged(SeekBar seekBar, int level,
boolean fromTouch) {
if (seekBar == bass_boost) {
bb.setEnabled(level > 0 ? true : false);
bb.setStrength((short) level); // Already in the right range 0-1000
} else if (eq != null) {
int new_level = min_level + (max_level - min_level) * level / 100;
for (int i = 0; i < num_sliders; i++) {
if (sliders[i] == seekBar) {
eq.setBandLevel((short) i, (short) new_level);
break;
}
}
}
}
/*=============================================================================
onStartTrackingTouch
=============================================================================*/
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
/*=============================================================================
onStopTrackingTouch
=============================================================================*/
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
/*=============================================================================
formatBandLabel
=============================================================================*/
public String formatBandLabel(int[] band) {
return milliHzToString(band[0]);
/**
change
/*/
}
/*=============================================================================
milliHzToString
=============================================================================*/
public String milliHzToString(int milliHz) {
if (milliHz < 1000) return "";
if (milliHz < 1000000)
return "" + (milliHz / 1000);
else
return "" + (milliHz / 1000000) + "k";
}
/*=============================================================================
updateSliders
=============================================================================*/
public void updateSliders() {
for (int i = 0; i < num_sliders; i++) {
int level;
if (eq != null)
level = eq.getBandLevel((short) i);
else
level = 0;
int pos = 100 * level / (max_level - min_level) + 50;
sliders[i].setProgress(pos);
}
}
/*=============================================================================
updateBassBoost
=============================================================================*/
public void updateBassBoost() {
if (bb != null)
bass_boost.setProgress(bb.getRoundedStrength());
else
bass_boost.setProgress(0);
}
/*=============================================================================
onCheckedChange
=============================================================================*/
@Override
public void onCheckedChanged(CompoundButton view, boolean isChecked) {
if (view == (View) enabled) {
eq.setEnabled(isChecked);
bb.setEnabled(true);
vr.setEnabled(true);
}
}
/*=============================================================================
updateUI
=============================================================================*/
public void updateUI() {
updateSliders();
updateBassBoost();
enabled.setChecked(eq.getEnabled());
}
/*=============================================================================
setFlat
=============================================================================*/
public void setFlat() {
if (eq != null) {
for (int i = 0; i < num_sliders; i++) {
eq.setBandLevel((short) i, (short) 0);
}
}
if (bb != null) {
bb.setEnabled(false);
bb.setStrength((short) 0);
}
updateUI();
}
/*=============================================================================
showAbout
/*=============================================================================
onOptionsItemSelected
=============================================================================*/
@Override
public boolean onOptionsItemSelected(MenuItem item) {
return super.onOptionsItemSelected(item);
}
}
希望它会对某人有所帮助。