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1.android如何做到播放音乐时动态波形
2.android平台的音音乐音乐播放器，播放音乐（这应该是乐播一个很耗时的操作）能不能在子线程中实现？

android如何做到播放音乐时动态波形

       1. 确保MediaPlayer正确创建并播放音乐。

       2. 检查Visualizer和Equalizer的放源实例化是否在正确的生命周期内。

       3. 确保在Activity暂停时正确释放Visualizer、码a码fusionapp 源码Equalizer和MediaPlayer资源。播放

       4. 修改VisualizerView的器源2018秒余额源码onDraw方法，确保正确绘制波形和频谱。音音乐

       5. 添加必要的乐播错误处理和日志输出，以便调试。放源

       修改后的码a码代码如下：

       ```java

       package com.AudioFx;

       import android.app.Activity;

       import android.content.Context;

       import android.graphics.Canvas;

       import android.graphics.Color;

       import android.graphics.Paint;

       import android.graphics.Rect;

       import android.media.AudioManager;

       import android.media.MediaPlayer;

       import android.media.audiofx.Equalizer;

       import android.media.audiofx.Visualizer;

       import android.os.Bundle;

       import android.util.Log;

       import android.view.Gravity;

       import android.view.View;

       import android.view.ViewGroup;

       import android.view.WindowManager;

       import android.widget.LinearLayout;

       import android.widget.SeekBar;

       import android.widget.TextView;

       public class AudioFxActivity extends Activity {

        private static final String TAG = "AudioFxActivity";

        private static final float VISUALIZER_HEIGHT_DIP = f;

        private MediaPlayer mMediaPlayer;

        private Visualizer mVisualizer;

        private Equalizer mEqualizer;

        private LinearLayout mLinearLayout;

        private VisualizerView mVisualizerView;

        private TextView mStatusTextView;

        private TextView mInfoView;

        @Override

        public void onCreate(Bundle icicle) {

        super.onCreate(icicle);

        mStatusTextView = new TextView(this);

        mLinearLayout = new LinearLayout(this);

        mLinearLayout.setOrientation(LinearLayout.VERTICAL);

        mLinearLayout.addView(mStatusTextView);

        setContentView(mLinearLayout);

        // Create the MediaPlayer

        try {

        mMediaPlayer = MediaPlayer.create(this, R.raw.my_life);

        } catch (Exception e) {

        Log.e(TAG, "Error creating MediaPlayer", e);

        finish();

        return;

        }

        Log.d(TAG, "MediaPlayer audio session ID: " + mMediaPlayer.getAudioSessionId());

        setupVisualizerFxAndUI();

        setupEqualizerFxAndUI();

        getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

        setVolumeControlStream(AudioManager.STREAM_MUSIC);

        mMediaPlayer.start();

        mStatusTextView.setText("Playing music...");

        }

        private void setupEqualizerFxAndUI() {

        // Create the Equalizer object (an AudioEffect subclass) and attach it

        // to our media player, with a default priority (0).

        mEqualizer = new Equalizer(0, mMediaPlayer.getAudioSessionId());

        mEqualizer.setEnabled(true);

        TextView eqTextView = new TextView(this);

        eqTextView.setText("Equalizer:");

        mLinearLayout.addView(eqTextView);

        short bands = mEqualizer.getNumberOfBands();

        final short minEQLevel = mEqualizer.getBandLevelRange()[0];

        final short maxEQLevel = mEqualizer.getBandLevelRange()[1];

        for (short i = 0; i < bands; i++) {

        final short band = i;

        TextView freqTextView = new TextView(this);

        freqTextView.setLayoutParams(new ViewGroup.LayoutParams(

        ViewGroup.LayoutParams.WRAP_CONTENT,

        ViewGroup.LayoutParams.WRAP_CONTENT));

        freqTextView.setGravity(Gravity.CENTER_HORIZONTAL);

        freqTextView.setText((mEqualizer.getCenterFreq(band) / ) + " Hz");

        mLinearLayout.addView(freqTextView);

        LinearLayout row = new LinearLayout(this);

        row.setOrientation(LinearLayout.HORIZONTAL);

        TextView minDbTextView = new TextView(this);

        minDbTextView.setLayoutParams(new ViewGroup.LayoutParams(

        ViewGroup.LayoutParams.WRAP_CONTENT,

        ViewGroup.LayoutParams.WRAP_CONTENT));

        minDbTextView.setText((minEQLevel / ) + " dB");

        row.addView(minDbTextView);

        TextView maxDbTextView = new TextView(this);

        maxDbTextView.setLayoutParams(new ViewGroup.LayoutParams(

        ViewGroup.LayoutParams.WRAP_CONTENT,

        ViewGroup.LayoutParams.WRAP_CONTENT));

        maxDbTextView.setText((maxEQLevel / ) + " dB");

        row.addView(maxDbTextView);

        SeekBar bar = new SeekBar(this);

        bar.setLayoutParams(new ViewGroup.LayoutParams(

        ViewGroup.LayoutParams.FILL_PARENT,

        ViewGroup.LayoutParams.WRAP_CONTENT));

        bar.setMax(maxEQLevel - minEQLevel);

        bar.setProgress(mEqualizer.getBandLevel(band));

        bar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {

        @Override

        public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {

        mEqualizer.setBandLevel(band, (short) (progress + minEQLevel));

        }

        @Override

        public void onStartTrackingTouch(SeekBar seekBar) {

        }

        @Override

        public void onStopTrackingTouch(SeekBar seekBar) {

        }

        });

        row.addView(bar);

        mLinearLayout.addView(row);

        }

        }

        private void setupVisualizerFxAndUI() {

        mVisualizerView = new VisualizerView(this);

        mVisualizerView.setLayoutParams(new ViewGroup.LayoutParams(

        ViewGroup.LayoutParams.FILL_PARENT,

        (int) (VISUALIZER_HEIGHT_DIP * getResources().getDisplayMetrics().density)));

        mLinearLayout.addView(mVisualizerView);

        mInfoView = new TextView(this);

        String infoStr = "";

        int[] csr = Visualizer.getCaptureSizeRange();

        if (csr != null) {

        String csrStr = "CaptureSizeRange: ";

        for (int i = 0; i < csr.length; i++) {

        csrStr += csr[i];

        csrStr += " ";

        }

        infoStr += csrStr;

        }

        final int maxCR = Visualizer.getMaxCaptureRate();

        infoStr = infoStr + "\nMaxCaptureRate: " + maxCR;

        mInfoView.setText(infoStr);

        mLinearLayout.addView(mInfoView);

        mVisualizer = new Visualizer(mMediaPlayer.getAudioSessionId());

        mVisualizer.setCaptureSize();

        mVisualizer.setDataCaptureListener(new Visualizer.OnDataCaptureListener() {

        @Override

        public void onWaveFormDataCapture(Visualizer visualizer, byte[] bytes, int samplingRate) {

        mVisualizerView.updateVisualizer(bytes);

        }

        @Override

        public void onFftDataCapture(Visualizer visualizer, byte[] fft, int samplingRate) {

        mVisualizerView.updateVisualizer(fft);

        }

        }, maxCR / 2, false, true);

        }

        @Override

        protected void onPause() {

        super.onPause();

android平台的音乐播放器，播放音乐（这应该是播放一个很耗时的操作）能不能在子线程中实现？

       Android平台实现音乐播放器，如果单单将播放音乐的器源操作放在子线程中进行会有一些问题：

       Thread所在的Activity优先级低，容易被系统杀死。音音乐map中hashcode源码如果程序在后台，乐播Thread所在的放源Activity很可能因为内存不足被系统杀死。（音乐播放器常常会在后台运行，店铺交易转让源码因为用户往往在听歌时会浏览其他应用。）

       如果在播放音乐时需要更新Activity的UI界面，单单运用Thread会播出异常。html烟火源码

       参考思路：可以将播放音乐的操作放在Service中进行，如果需要更新UI，可以使用Hanlder与Activity建立通信。