TextView不用获取焦点也能实现跑马灯

1.写一个类继承TextView

package com.example.tt;
import android.content.Context;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.widget.TextView;

public class ScrollingTextView extends TextView {

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

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

    public ScrollingTextView(Context context) {
        super(context);
    }
    @Override
    protected void onFocusChanged(boolean focused, int direction, Rect previouslyFocusedRect) {
        if(focused)
            super.onFocusChanged(focused, direction, previouslyFocusedRect);
    }

    @Override
    public void onWindowFocusChanged(boolean focused) {
        if(focused)
            super.onWindowFocusChanged(focused);
    }


    @Override
    public boolean isFocused() {
        return true;
    }

}

2.xml 中增加属性

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<com.example.tt.ScrollingTextView
     android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="80dip"
        android:layout_marginBottom="25dip"
        android:textSize="25sp"
        android:singleLine="true"
        android:textColor="@android:color/black"
        android:ellipsize="marquee"
        android:focusable="true"
        android:marqueeRepeatLimit="marquee_forever"
        android:focusableInTouchMode="true"
        android:scrollHorizontally="true"
        android:text="这才是真正的文字跑马灯效果,文字移动速度，文字移动方向，文字移动的样式，动画等等……"
        android:background="#2FFFFFFF" />

<Button
    android:id="@+id/button1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Button" />

</LinearLayout>

3. 在activity中声明

package com.example.tt;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;

public class MainActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

}