动画时间长短不一

Question

我有一个TextView，可通过以下方式在其上应用动画：

TextView txtStatus = (TextView) view.findViewById( R.id.txtStatus );

Animation animation = new Animation() 
{
    @Override
    protected void applyTransformation( float interpolatedTime, Transformation t ) 
    {
        Log.d( "Debug", "ALPHA: " + interpolatedTime );
    }
};
animation.setDuration( 700 );
txtStatus.clearAnimation();
txtStatus.startAnimation( animation );

问题在于，无论出于什么原因，第二次调用动画时，动画都短得多，并直接跳到0.9，而不是逐渐增大。

这也很奇怪，它大约有50％的时间发生。

输出示例：

First time executed:
    ALPHA: 0.0
    ALPHA: 0.0
    ALPHA: 0.005809784
    ALPHA: 0.022434622
    ALPHA: 0.034290344
    ALPHA: 0.049515605
    ALPHA: 0.066241235
    ALPHA: 0.086459756
    ALPHA: 0.10768908
    ALPHA: 0.13245812
    ALPHA: 0.15936571
    ALPHA: 0.18650392
    ALPHA: 0.21710521
    ALPHA: 0.24741328
    ALPHA: 0.3159377
    ALPHA: 0.38655293
    ALPHA: 0.45965204
    ALPHA: 0.53363454
    ALPHA: 0.5715612
    ALPHA: 0.64379966
    ALPHA: 0.7128896
    ALPHA: 0.74479985
    ALPHA: 0.8082236
    ALPHA: 0.83567554
    ALPHA: 0.8866831
    ALPHA: 0.90971905
    ALPHA: 0.94752276
    ALPHA: 0.962368
    ALPHA: 0.9859218
    ALPHA: 0.9931222
    ALPHA: 0.9999194
    ALPHA: 1.0
    ALPHA: 1.0

Second time executed:
    ALPHA: 0.0
    ALPHA: 0.0
    ALPHA: 0.90318537
    ALPHA: 0.9292244
    ALPHA: 0.94752276
    ALPHA: 0.96321744
    ALPHA: 0.9762169
    ALPHA: 0.98644567
    ALPHA: 0.99798715
    ALPHA: 1.0
    ALPHA: 1.0

请问有人提示我做错了什么？谢谢！