Android SurfaceView预览变形完美解决方法

  @Override
  public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
    Log.i(TAG, "surfaceChanged: " + width + " " + height);
  }

protected void updateWindow(boolean force, boolean redrawNeeded) {
    ...代码省略

    int myWidth = mRequestedWidth;
    if (myWidth <= 0) myWidth = getWidth();
    int myHeight = mRequestedHeight;
    if (myHeight <= 0) myHeight = getHeight();

    ...代码省略
      
    if (creating || formatChanged || sizeChanged
        || visibleChanged || realSizeChanged) {
      if (DEBUG) Log.i(TAG, System.identityHashCode(this) + " "
          + "surfaceChanged -- format=" + mFormat
          + " w=" + myWidth + " h=" + myHeight);
      if (callbacks == null) {
        callbacks = getSurfaceCallbacks();
      }
      for (SurfaceHolder.Callback c : callbacks) {
        c.surfaceChanged(mSurfaceHolder, mFormat, myWidth, myHeight);
      }
    }
    
    ...代码省略
  }

@Override
    public void setFixedSize(int width, int height) {
      if (mRequestedWidth != width || mRequestedHeight != height) {
        mRequestedWidth = width;
        mRequestedHeight = height;
        requestLayout();
      }
    }

public class ResizeAbleSurfaceView extends SurfaceView {

  private int mWidth = -1;
  private int mHeight = -1;

  public ResizeAbleSurfaceView(Context context) {
    super(context);
  }

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

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

  @Override
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    if (-1 == mWidth || -1 == mHeight) {
      super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }
    else {
      setMeasuredDimension(mWidth, mHeight);
    }
  }

  public void resize(int width, int height) {
    mWidth = width;
    mHeight = height;
    getHolder().setFixedSize(width, height);
    requestLayout();
    invalidate(); 
  }
}