Activity中操作xml布局

<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"
    tools:context=".MainActivity" >

    <HorizontalScrollView
        android:id="@+id/sc"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:scrollbars="none" >

        <LinearLayout
            android:id="@+id/line_sc"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" >
        </LinearLayout>
    </HorizontalScrollView>

    <LinearLayout
        android:id="@+id/view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/sc"
      />

    <android.support.v4.view.ViewPager
        android:id="@+id/vp"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_below="@id/view" >
    </android.support.v4.view.ViewPager>

</RelativeLayout>

package com.bwie.test;

import java.util.ArrayList;

import com.bwie.adapter.MyAdapter;
import com.bwie.fragment.F1;
import com.bwie.utils.Myutil;

import android.os.Bundle;
import android.app.Activity;
import android.graphics.Color;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.util.DisplayMetrics;
import android.view.Menu;
import android.view.View;
import android.widget.HorizontalScrollView;
import android.widget.LinearLayout;
import android.widget.LinearLayout.LayoutParams;
import android.widget.TextView;

public class MainActivity extends FragmentActivity {

    private LinearLayout line_sc;
    private HorizontalScrollView sc;
    private String[] column = new String[] { "舍内要闻", "本社介绍", "履行职能", "自身建设",
            "社员风采", "自我介绍", "校内趣闻", "爆料" };
    private ArrayList<Fragment> list;
    private ViewPager vp;
    private int widthPixels;
    private ArrayList<TextView> list_view;

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

        /**
         * 获取窗口的 宽度
         */
        widthPixels=getWindowManager().getDefaultDisplay().getWidth();

        // 初始化数据
        init();

        // 获取栏目的数据
        getColumn();

        // 创建fragment数据
        setFragment();

        // 为vp设置数据
        FragmentManager fm = getSupportFragmentManager();
        vp.setAdapter(new MyAdapter(fm, list));
        
        setTitle_1(vp.getCurrentItem());

        // 为vp设置页面滑动监听
        vp.setOnPageChangeListener(new OnPageChangeListener() {

            @Override
            public void onPageSelected(int arg0) {
                 
                //设置游标
                setTitle_1(arg0);
                
                //设置滑动
                setAutoScroll(arg0);

            }

        
            @Override
            public void onPageScrolled(int arg0, float arg1, int arg2) {
                // TODO Auto-generated method stub

            }

            @Override
            public void onPageScrollStateChanged(int arg0) {
                // TODO Auto-generated method stub

            }
        });

    }

    protected void setAutoScroll(int p) {
        // TODO Auto-generated method stub
        
        //获取当前要展示的游标
        TextView textView = list_view.get(p);
        //获取其宽度
        int w = textView.getMeasuredWidth();
        int left = textView.getLeft();
        int address=left-widthPixels/2;
        
        sc.smoothScrollTo(address, 0);
        
        
        
    }

    private void setFragment() {

        // 创建集合存放fragment对象
        list = new ArrayList<Fragment>();
        for (int i = 0; i < column.length; i++) {
            F1 f1 = new F1();

            // 传值
            Bundle b = new Bundle();
            b.putInt("column", i);
            f1.setArguments(b);

            // 将创建的fragment添加到集合中
            list.add(f1);
        }
    }
    private void setTitle_1(int arg0) {
        //设置当前显示的textview控件
        TextView textView = list_view.get(arg0);
        //将当前的textview显示
        textView.setVisibility(View.VISIBLE);
        
        for(int i=0;i<list_view.size();i++)
        {
            TextView tv = list_view.get(i);
            
            if(tv!=textView)
            {
                tv.setVisibility(View.GONE);
            }
        }
    }


    private void getColumn() {
        // TODO Auto-generated method stub

     list_view = new ArrayList<TextView>();
        for (int i = 0; i < column.length; i++) {

            // 创建线性布局来整体作为水平滚动的子布局
            LinearLayout sc = new LinearLayout(MainActivity.this);
            // 设置线性布局的排列方式(垂直)
            sc.setOrientation(1);
            sc.setPadding(30, 0, 0, 0);

            // 1.首先向线性布局中添加textview
            // 创建textview
            TextView tv = new TextView(MainActivity.this);
            // 为tv设置数据
            tv.setText(column[i]);
            LinearLayout.LayoutParams params = new LayoutParams(
                    widthPixels / 5, LayoutParams.WRAP_CONTENT);
            sc.addView(tv, params);

            // 2.向线性布局中添加下面的横线
            TextView tv_line = new TextView(MainActivity.this);
            LinearLayout.LayoutParams params_2 = new LayoutParams(
                    widthPixels / 5, 10);
            tv_line.setBackgroundColor(Color.GRAY);
            tv_line.setVisibility(View.INVISIBLE);
            list_view.add(tv_line);
            sc.addView(tv_line, params_2);

            // 将数据添加到 线性布局中
            line_sc.addView(sc);
        }

    }

    private void init() {
        line_sc = (LinearLayout) findViewById(R.id.line_sc);
        sc = (HorizontalScrollView) findViewById(R.id.sc);
        vp = (ViewPager) findViewById(R.id.vp);

    }

}