如何在Android應用中錄製/播放音頻時創建正弦波動畫？

Question

在iOS應用程序中創建很容易。任何人都可以在錄製和播放音頻的同時告訴我創建Sinwave動畫的簡單方法。我嘗試了很多方法，但是我做不到。有沒有第三方框架？

任何一個可以幫我請..

Answer 1

使用下面的代碼來獲得像IOS波形...得到錄像機的幅度，並傳遞給updateAmplitude（）函數來獲得聲音的變化。

public class WaveFormView extends View { 

     private static final float defaultFrequency   = 1.5f; 
     private static final float defaultAmplitude   = 1.0f; 
     private static final float defaultIdleAmplitude  = 0.01f; 
     private static final float defaultNumberOfWaves  = 5.0f; 
     private static final float defaultPhaseShift   = -0.15f; 
     private static final float defaultDensity   = 5.0f; 
     private static final float defaultPrimaryLineWidth = 3.0f; 
     private static final float defaultSecondaryLineWidth = 1.0f; 

     private float phase; 
     private float amplitude; 
     private float frequency; 
     private float idleAmplitude; 
     private float numberOfWaves; 
     private float phaseShift; 
     private float density; 
     private float primaryWaveLineWidth; 
     private float secondaryWaveLineWidth; 
     Paint mPaintColor; 
     Rect rect; 
     boolean isStraightLine = false; 

     public WaveFormView(Context context) { 
      super(context); 
      setUp(); 
     } 

     public WaveFormView(Context context, AttributeSet attrs) { 
      super(context, attrs); 
      setUp(); 
     } 

     public WaveFormView(Context context, AttributeSet attrs, int defStyleAttr) { 
      super(context, attrs, defStyleAttr); 
      setUp(); 
     } 

     @TargetApi(Build.VERSION_CODES.LOLLIPOP) 
     public WaveFormView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { 
      super(context, attrs, defStyleAttr, defStyleRes); 
      setUp(); 
     } 

     private void setUp() { 
      this.frequency = defaultFrequency; 

      this.amplitude = defaultAmplitude; 
      this.idleAmplitude = defaultIdleAmplitude; 

      this.numberOfWaves = defaultNumberOfWaves; 
      this.phaseShift = defaultPhaseShift; 
      this.density = defaultDensity; 

      this.primaryWaveLineWidth = defaultPrimaryLineWidth; 
      this.secondaryWaveLineWidth = defaultSecondaryLineWidth; 
      mPaintColor = new Paint(); 
      mPaintColor.setColor(Color.WHITE); 
     } 

     public void updateAmplitude(float ampli, boolean isSpeaking) { 
      this.amplitude = Math.max(ampli, idleAmplitude); 
      isStraightLine = isSpeaking; 
     } 


     @Override 
     protected void onDraw(Canvas canvas) { 
      rect = new Rect(0,0,canvas.getWidth(),canvas.getWidth()); 
      canvas.drawColor(Color.BLUE); 
      /*canvas.drawRect(rect, mPaintColor);*/ 
      if(isStraightLine) { 
       for (int i = 0; i < numberOfWaves; i++) { 
        mPaintColor.setStrokeWidth(i == 0 ? primaryWaveLineWidth : secondaryWaveLineWidth); 
        float halfHeight = canvas.getHeight()/2; 
        float width = canvas.getWidth(); 
        float mid = canvas.getWidth()/2; 

        float maxAmplitude = halfHeight - 4.0f; 
        float progress = 1.0f - (float) i/this.numberOfWaves; 
        float normedAmplitude = (1.5f * progress - 0.5f) * this.amplitude; 
        Path path = new Path(); 

        float multiplier = Math.min(1.0f, (progress/3.0f * 2.0f) + (1.0f/3.0f)); 

        for (float x = 0; x < width + density; x += density) { 
         // We use a parable to scale the sinus wave, that has its peak in the middle of the view. 
         float scaling = (float) (-Math.pow(1/mid * (x - mid), 2) + 1); 

         float y = (float) (scaling * maxAmplitude * normedAmplitude * Math.sin(2 * Math.PI * (x/width) * frequency + phase) + halfHeight); 

         if (x == 0) { 
          path.moveTo(x, y); 
         } else { 
          path.lineTo(x, y); 
         } 
        } 
        mPaintColor.setStyle(Paint.Style.STROKE); 
        mPaintColor.setAntiAlias(true); 
        canvas.drawPath(path, mPaintColor); 

       } 
      } else { 
       canvas.drawLine(5,canvas.getHeight()/2,canvas.getWidth(),canvas.getHeight()/2,mPaintColor); 
       canvas.drawLine(0,canvas.getHeight()/2,canvas.getWidth(),canvas.getHeight()/2,mPaintColor); 
       canvas.drawLine(-5, canvas.getHeight()/2, canvas.getWidth(), canvas.getHeight()/2,mPaintColor); 
      } 
      this.phase += phaseShift; 
      invalidate(); 
     } 
}