TextView实现多个TextView对象的走马灯效果

1：自定义一个控件继承TextView,重写isFocused方法，返回值为true;

package com.example.helloandroid;

import android.R.bool;
import android.content.Context;
import android.util.AttributeSet;
import android.view.ViewDebug.ExportedProperty;
import android.widget.TextView;

public class MarqueeText extends TextView {

    public MarqueeText(Context context) {
        super(context);
        // TODO Auto-generated constructor stub
    }

    public MarqueeText(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        // TODO Auto-generated constructor stub
    }

    public MarqueeText(Context context, AttributeSet attrs) {
        super(context, attrs);
        // TODO Auto-generated constructor stub
    }
    @Override
    @ExportedProperty(category = "focus")
    public boolean isFocused() {
        // TODO Auto-generated method stub
        return true;
    }
}

2：给两个text空间添加属性，记得一定加上包名以及类名 

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <com.example.helloandroid.MarqueeText
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:singleLine="true"
        android:ellipsize="marquee"
        android:focusable="true"
        android:focusableInTouchMode="true"
        android:text="@string/hello_world" />

    
    <com.example.helloandroid.MarqueeText
        android:layout_below="@id/textView1"
        android:layout_margin="10dp"
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:singleLine="true" 
        android:ellipsize="marquee"
        android:focusable="true"
        android:focusableInTouchMode="true"
        android:text="@string/hello_world" />
</RelativeLayout>