您可以把甲型六氯环己烷同此刻一样。

int alpha = 0;
((TextView)findViewById(R.id.t1)).setTextColor(Color.argb(alpha, 255, 0, 0));

as the alpha you getting from the seekbar that will be set into the text color

这为我工作:

<>1>。 创建<>AlphaTextView:

public class AlphaTextView extends TextView {

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

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

  public AlphaTextView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
  }

  @Override
  public boolean onSetAlpha(int alpha) 
  {
    setTextColor(getTextColors().withAlpha(alpha));
    setHintTextColor(getHintTextColors().withAlpha(alpha));
    setLinkTextColor(getLinkTextColors().withAlpha(alpha));
    getBackground().setAlpha(alpha);
    return true;
  }    
}

<>2>。 添加这段文字,而不是用文字写成文view:

...
   <!--use complete path to AlphaTextView in following tag-->
   <com.xxx.xxx.xxx.AlphaTextView
         android:layout_width="fill_parent"
         android:layout_height="wrap_content"
         android:text="sample alpha textview"
         android:gravity="center"
         android:id="@+id/at"
         android:textColor="#FFFFFF"
         android:background="#88FF88"
        />
...

<>3>。 现在,你可以在你的活动中利用这一案文:

at=(AlphaTextView)findViewById(R.id.at);

at.onSetAlpha(255); // To make textview 100% opaque
at.onSetAlpha(0); //To make textview completely transperent

如今,在XML中,有一席之地。

甲型六氯环己烷

a. 通过Layout改变Opacity

改动方法:

public void onProgressChanged(SeekBar seekBar, int progress, boolean fromTouch)
{
    classicText.setAlpha((float)(gameSelector.getProgress())/(float)(seekBar.getMax()));
}

也许晚了,但如果现在有人想到这一点的话,你们都必须做到:

textView.setAlpha();

括号内的条目编号为0至1

I think this is a simple way to set alpha or opacity programmatically for TextView. By using function withAlpha after getTextColors from textView.

// alpha value between 0..255
// 0 for transparent
classicText.setTextColor(classicText.textColors.withAlpha(100))

页: 1 阿尔法(float xxx);

iii

int progress = gameSelector.getProgress();
int maxProgress = gameSelector.getMax();
float opacity = (progress / maxProgress)*255;
classicText.setAlpha(opacity);