android中viewPager实现的屏幕左右切换(入门篇)

大多数的APP都可以实现几个屏幕来回的切换，

首先新建两个Activity，内容随意，布局随意。接下来在MainActivity.xml：

<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" >

    <android.support.v4.view.ViewPager
        android:id="@+id/viewpager"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" >
    </android.support.v4.view.ViewPager>

</RelativeLayou

不要忘记android-support-v4包，目前4.0以上版本都自带

接下来是java中的方法：

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        viewPager = (ViewPager) findViewById(R.id.viewpager);
        View view1 = LayoutInflater.from(MainActivity.this).inflate(R.layout.a,
                null);
        View view2 = LayoutInflater.from(MainActivity.this).inflate(R.layout.b,
                null);
        list = new ArrayList<View>();
        list.add(view1);
        list.add(view2);
        viewPager.setAdapter(new MyAdapter());
    }

class MyAdapter extends PagerAdapter {

        @Override
        public int getCount() {
            return list.size();
        }

        @Override
        public boolean isViewFromObject(View arg0, Object arg1) {
            return arg0 == arg1;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            return titlelist.get(position);

        }

        @Override
        public Object instantiateItem(View container, int position) {
            ((ViewPager) container).addView(list.get(position));
            return list.get(position);
        }

        @Override
        public void destroyItem(View container, int position, Object object) {
            super.destroyItem(container, position, object);
            ((ViewPager) container).removeView(list.get(position));
        }
    }

至此就可以实现两个屏幕的切换