public class HightLightTextView extends TextView {

    // 存储view的宽度

    private int mTextViewWidth = 0;

    // 画笔

    private Paint mPaint;

    // 线性渲染

    private LinearGradient mLinearGradient;

    // 存储变换的matrix

    private Matrix matrix;

    // 移动距离

    private int mTranslateX = 0;

    // 构造方法

    public HightLightTextView(Context context) {

        this(context, null);

    }

    public HightLightTextView(Context context, AttributeSet attrs) {

        this(context, attrs, 0);

    }

    public HightLightTextView(Context context, AttributeSet attrs, int defStyle) {

        super(context, attrs, defStyle);

    }

    /**

     * view的调用过程:构造方法->onFinishInflate->onSizeChanged->onDraw

     */

    @Override

    protected void onSizeChanged(int w, int h, int oldw, int oldh) {

        super.onSizeChanged(w, h, oldw, oldh);

        // 获取view的宽度，初始化画笔等初始属性

        if (mTextViewWidth == 0) {

            mTextViewWidth = getMeasuredWidth();

            // 如果宽度大于0的话，则初始化

            if (mTextViewWidth > 0) {

                // 初始化画笔

                mPaint = getPaint();

                // 线性渲染

                mLinearGradient = new LinearGradient(0, getMeasuredHeight(), mTextViewWidth, 0,

                        new int[]{0X55FFFFFF, 0XFFFFFFFF, 0X55FFFFFF},

                        new float[]{0, 0.5f, 1}, Shader.TileMode.CLAMP);

                mPaint.setShader(mLinearGradient);

                matrix = new Matrix();

            }

        }

    }

    @Override

    protected void onDraw(Canvas canvas) {

        super.onDraw(canvas);

        if (matrix != null) {

            mTranslateX += mTextViewWidth / 10;

            // 如果移动的距离大于两倍的宽度，则重新开始移动

            if (mTranslateX > 2 * mTextViewWidth) {

                mTranslateX = -mTextViewWidth;

            }

            // 平移matrix

            matrix.setTranslate(mTranslateX, 0);

            // 设置线性变化的matrix

            mLinearGradient.setLocalMatrix(matrix);

            // 延迟50ms重绘  (重绘时会重新调用onDraw)

            postInvalidateDelayed(50);

        }

    }

}