在我们开发过程中，跑马灯这个功能非常实用的，在实现这个功能的时候，这个时候我们通常需要找demo来实现这个方法，我从github上面找到这个demo感觉很好用，所以就要实现了这个功能喽MarqueeView，看这个工具类，因为我找这个类的时候是没有点击事件的，所以我给它加了一个点击事件，看这个工具类

public class MarqueeView extends ViewFlipper {

    private Context mContext;
    private List<String> notices;
    private boolean isSetAnimDuration = false;
    private int contentSize;
    private int interval = 1000;
    private int animDuration = 500;
    private int textSize = 14;
    private int textColor = 0xffffffff;
    private int gravity = Gravity.LEFT | Gravity.CENTER_VERTICAL;
    //点击事件
    private OnItemClickListener onItemClickListener;

    public MarqueeView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context, attrs, 0);
    }

    private void init(Context context, AttributeSet attrs, int defStyleAttr) {
        this.mContext = context;
        if (notices == null) {
            notices = new ArrayList<>();
        }

        TypedArray typedArray = getContext().obtainStyledAttributes(attrs, R.styleable.MarqueeViewStyle, defStyleAttr, 0);
        interval = typedArray.getInteger(R.styleable.MarqueeViewStyle_mvInterval, interval);
        isSetAnimDuration = typedArray.hasValue(R.styleable.MarqueeViewStyle_mvAnimDuration);
        animDuration = typedArray.getInteger(R.styleable.MarqueeViewStyle_mvAnimDuration, animDuration);
        if (typedArray.hasValue(R.styleable.MarqueeViewStyle_mvTextSize)) {
            textSize = (int) typedArray.getDimension(R.styleable.MarqueeViewStyle_mvTextSize, textSize);
            textSize = DisplayUtil.px2sp(mContext, textSize);
        }
        textColor = typedArray.getColor(R.styleable.MarqueeViewStyle_mvTextColor, textColor);
        typedArray.recycle();

        setFlipInterval(interval);

        Animation animIn = AnimationUtils.loadAnimation(mContext, R.anim.anim_marquee_in);
        if (isSetAnimDuration) animIn.setDuration(animDuration);
        setInAnimation(animIn);

        Animation animOut = AnimationUtils.loadAnimation(mContext, R.anim.anim_marquee_out);
        if (isSetAnimDuration) animOut.setDuration(animDuration);
        setOutAnimation(animOut);
    }

    // 根据公告字符串启动轮播
    public void startWithText(final String notice) {
        if (TextUtils.isEmpty(notice)) return;
        getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
            @Override
            public void onGlobalLayout() {
                getViewTreeObserver().removeGlobalOnLayoutListener(this);
                startWithFixedWidth(notice, getWidth());
            }
        });
    }

    // 根据公告字符串列表启动轮播
    public void startWithList(List<String> notices) {
        setNotices(notices);
        start();
    }

    // 根据宽度和公告字符串启动轮播
    private void startWithFixedWidth(String notice, int width) {
        int noticeLength = notice.length();
        int dpW = DisplayUtil.px2dip(mContext, width);
        int limit = dpW / textSize;
        if (dpW == 0) {
            throw new RuntimeException("Please set MarqueeView width !");
        }

        if (noticeLength <= limit) {
            notices.add(notice);
        } else {
            int size = noticeLength / limit + (noticeLength % limit != 0 ? 1 : 0);
            for (int i = 0; i < size; i++) {
                int startIndex = i * limit;
                int endIndex = ((i + 1) * limit >= noticeLength ? noticeLength : (i + 1) * limit);
                notices.add(notice.substring(startIndex, endIndex));
            }
        }
        start();
    }

    // 启动轮播
    public boolean start() {
        if (notices == null || notices.size() == 0) return false;
        removeAllViews();

        for (int i = 0; i < notices.size(); i++) {
            final TextView textView = createTextView(notices.get(i), i);
            final int finalI = i;
            textView.setOnClickListener(new OnClickListener() {
                @Override
                public void onClick(View v) {
                    if (onItemClickListener != null) {
                        onItemClickListener.onItemClick(finalI, textView);
                    }
                }
            });
            addView(textView);
        }

        if (notices.size() > 1) {
            startFlipping();
        }
        return true;
    }

    // 创建ViewFlipper下的TextView
    private TextView createTextView(String text, int position) {
        TextView tv = new TextView(mContext);
        tv.setGravity(gravity);
        tv.setText(text);
        tv.setTextColor(textColor);
        tv.setTextSize(textSize);
        tv.setTag(position);
        return tv;
    }

    public List<String> getNotices() {
        return notices;
    }

    public void setNotices(List<String> notices) {
        this.notices = notices;
    }

    public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
        this.onItemClickListener = onItemClickListener;
    }

    public interface OnItemClickListener {
        void onItemClick(int position, TextView textView);
    }

}

这就是它实现的方式，我从中加了点击事件，所以它的用法是这样的

<com.redsun.property.views.MarqueeView
    android:id="@+id/vertical_switch_textview1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerInParent="true"
    android:layout_toLeftOf="@+id/total_quantity"
    android:layout_toRightOf="@+id/news_image"
    android:background="@color/white"
    android:ellipsize="end"
    android:maxEms="10"
    android:maxLength="10"
    android:textColor="@color/gray_dark"
    android:textSize="@dimen/font_normal"
    app:mvAnimDuration="1000"
    app:mvInterval="3000"
    app:mvTextColor="@color/black"
    app:mvTextSize="14sp"
    tools:text="弘生活APP改版了"
    />

verticalSwitchTextView1 = (MarqueeView) rootView.findViewById(R.id.vertical_switch_textview1);
List<String> info = new ArrayList<>();
info.add("1.能够适应多行长文本的Android TextView的例子");
info.add("2.\"科比，！");
info.add("3. GitHub帐号：zhangyuanchong");
info.add("4.\"理解的也很简单，");
info.add("5. 破解密钥");
info.add("6. 实现了两种方式");
verticalSwitchTextView1.startWithList(info);
verticalSwitchTextView1.setOnItemClickListener(new MarqueeView.OnItemClickListener() {
    @Override
    public void onItemClick(int position, TextView textView) {
        position = position + 1;
        Toast.makeText(getActivity(), "点击了" + position, Toast.LENGTH_SHORT).show();
    }
});

这样就直接实现喽，其实还是蛮简单的呢。