进度条

<ProgressBar
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        style="?android:attr/progressBarStyleHorizontal"
        android:progress="50"
        android:secondaryProgress="60"
        android:max="90"
        android:id="@+id/sb2"/>
    <ProgressBar
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        style="?android:attr/progressBarStyleSmall"
        android:progress="50"
        android:secondaryProgress="60"
        android:max="80"
        android:id="@+id/sb3"
        android:visibility="visible"
        />

    <SeekBar
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:progress="100"
        android:secondaryProgress="60"
        android:max="80"
        android:id="@+id/sb1"/>

    <RatingBar
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:numStars="6"
        android:rating="3.5"
        android:isIndicator="false"/>
    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/aaa"
        android:id="@+id/sb4"
        android:alpha="1"

       />

 SeekBar sb1;
    ProgressBar sb2;
    ProgressBar sb3;
   int jd;
    ImageView sb4;

    //AlertDialog ad= new AlertDialog.Builder(this).create();


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_jindutiao);
        sb1=(SeekBar)findViewById(R.id.sb1);
        sb2=(ProgressBar)findViewById(R.id.sb2);
        sb3=(ProgressBar)findViewById(R.id.sb3);
        sb4=(ImageView)findViewById(R.id.sb4);

        sb1.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
            @Override
            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                //只要progress变化就会被触发
                //Toast.makeText(jindutiaoActivity.this, "当前进度=" + progress, Toast.LENGTH_SHORT).show();

                jd=progress;

                sb4.setAlpha(jd/100);
                Toast.makeText(jindutiaoActivity.this, "当前进度="+sb4.getAlpha(), Toast.LENGTH_SHORT).show();

                sb2.setProgress(jd);
                if(jd==sb2.getMax()){
                   sb3.setVisibility(View.INVISIBLE);//不显示位置保留
                }
                else {
                    sb3.setVisibility(View.VISIBLE);
                }

            }

            @Override
                public void onStartTrackingTouch(SeekBar seekBar) {
                Log.e("TAG","进度条开始拖动了");

            }

            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {
                Log.e("TAG","进度条停止拖动了");
            }
        });


    }