android(8) ViewPager页面滑动切换

一.ViewPager页面滑动切换实现：

   借鉴了别人的源码，还是比较容易实现的，而且这种效果还是经常使用的，特此记录一下：

效果图：

主界面：

public class MainActivity extends Activity {

	private ViewPager mPager;// 页卡内容
	private List<View> listViews; // Tab页面列表
	private ImageView cursor;// 动画图片
	private TextView t1, t2, t3;// 页卡头标
	private int offset = 0;// 动画图片偏移量
	private int currIndex = 0;// 当前页卡编号
	private int bmpW;// 动画图片宽度

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_tab_main);
		InitImageView();
		InitTextView();
		InitViewPager();
	}

	// 初始选项
	private void InitTextView() {
		t1 = (TextView) findViewById(R.id.text1);
		t2 = (TextView) findViewById(R.id.text2);
		t3 = (TextView) findViewById(R.id.text3);

		t1.setOnClickListener(new MyOnClickListener(0));
		t2.setOnClickListener(new MyOnClickListener(1));
		t3.setOnClickListener(new MyOnClickListener(2));
	}

	// 初始化ViewPager
	private void InitViewPager() {
		mPager = (ViewPager) findViewById(R.id.vPager);
		listViews = new ArrayList<View>();
		LayoutInflater mInflater = getLayoutInflater();
		listViews.add(mInflater
				.inflate(R.layout.activity_tab_one_pager, null));
		listViews.add(mInflater
				.inflate(R.layout.activity_tab_two_pager, null));
		listViews.add(mInflater
				.inflate(R.layout.activity_tab_three_pager, null));
		mPager.setAdapter(new MyViewPagerAdapter(listViews, this));
		//默认选中第一个页面
		mPager.setCurrentItem(0);
		mPager.setOnPageChangeListener(new MyOnPageChangeListener());
	}

	// 初始化动画
	private void InitImageView() {
		cursor = (ImageView) findViewById(R.id.cursor);
		bmpW = BitmapFactory.decodeResource(getResources(),
				R.drawable.icon_tab_page_bg).getWidth();// 获取图片宽度
		DisplayMetrics dm = new DisplayMetrics();
		getWindowManager().getDefaultDisplay().getMetrics(dm);
		int screenW = dm.widthPixels;// 获取分辨率宽度
		offset = (screenW / 3 - bmpW) / 2;// 计算偏移量
		Matrix matrix = new Matrix();
		matrix.postTranslate(offset, 0);
		cursor.setImageMatrix(matrix);// 设置动画初始位置
	}

	// 页卡监听
	public class MyOnClickListener implements View.OnClickListener {
		private int index = 0;

		public MyOnClickListener(int i) {
			index = i;
		}

		public void onClick(View v) {
			mPager.setCurrentItem(index);
		}
	};

	// 滑动监听
	public class MyOnPageChangeListener implements OnPageChangeListener {

		int one = offset * 2 + bmpW;// 页卡1 -> 页卡2 偏移量
		int two = one * 2;// 页卡1 -> 页卡3 偏移量
        //arg0表示页数
		public void onPageSelected(int arg0) {
			// TranslateAnimation位移动画
			Animation animation = null;
			//表示从第一个页卡跳转到当前页卡
			switch (arg0) {
			case 0:
				if (currIndex == 1) {
					animation = new TranslateAnimation(one, 0, 0, 0);
				} else if (currIndex == 2) {
					animation = new TranslateAnimation(two, 0, 0, 0);
				}
				break;
			case 1:
				if (currIndex == 0) {
					animation = new TranslateAnimation(offset, one, 0, 0);
				} else if (currIndex == 2) {
					animation = new TranslateAnimation(two, one, 0, 0);
				}
				break;
			case 2:
				if (currIndex == 0) {
					animation = new TranslateAnimation(offset, two, 0, 0);
				} else if (currIndex == 1) {
					animation = new TranslateAnimation(one, two, 0, 0);
				}
				break;
			}
			currIndex = arg0;
			animation.setFillAfter(true);// true:表示图片停在动画结束位置
			animation.setDuration(300);
			cursor.startAnimation(animation);
		}

		public void onPageScrolled(int arg0, float arg1, int arg2) {
		}

		public void onPageScrollStateChanged(int arg0) {
		}
	}

}

public class MyViewPagerAdapter extends PagerAdapter {
	private List<View> mListViews;
	private Context context;

	public MyViewPagerAdapter(List<View> mListViews, Context context) {
		this.mListViews = mListViews;
		this.context = context;
	}

	@Override
	public void destroyItem(View arg0, int arg1, Object arg2) {
		((ViewPager) arg0).removeView(mListViews.get(arg1));
	}

	@Override
	public void finishUpdate(View arg0) {
	}

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

	@Override
	public Object instantiateItem(View arg0, int arg1) {

		if (arg1 < 3) {
			((ViewPager) arg0).addView(mListViews.get(arg1 ), 0);
		}
		// 页卡内点击事件
		if (arg1 == 0) {
			Button btn = (Button) arg0.findViewById(R.id.btn);
			btn.setOnClickListener(new View.OnClickListener() {
				public void onClick(View v) {
					showDialog("1");
				}
			});
		}
		if (arg1 == 1) {
			Button btn = (Button) arg0.findViewById(R.id.btn);
			btn.setOnClickListener(new View.OnClickListener() {
				public void onClick(View v) {
					showDialog("2");
				}
			});
		}
		if (arg1 == 2) {
			Button btn = (Button) arg0.findViewById(R.id.btn);
			btn.setOnClickListener(new View.OnClickListener() {
				public void onClick(View v) {
					showDialog("3");
				}
			});
		}
		return mListViews.get(arg1);
	}

	public void showDialog(String arg) {
		new AlertDialog.Builder(context).setTitle("说明")
				.setMessage("这是第"+arg+"个页面")
				.setNegativeButton("确定", new DialogInterface.OnClickListener() {
					public void onClick(DialogInterface dialog, int which) {
					}
				}).show();
	}

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

	@Override
	public void restoreState(Parcelable arg0, ClassLoader arg1) {
	}

	@Override
	public Parcelable saveState() {
		return null;
	}

	@Override
	public void startUpdate(View arg0) {
	}

}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="#FF969696"
    android:orientation="vertical" >

    <LinearLayout
        android:id="@+id/linearLayout1"
        android:layout_width="fill_parent"
        android:layout_height="45dp"
        android:background="#FFDFD7D7" >

        <TextView
            android:id="@+id/text1"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:gravity="center"
            android:text="\n页卡1"
            android:textColor="#000000" />

        <TextView
            android:id="@+id/text2"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:gravity="center"
            android:text="\n页卡2"
            android:textColor="#000000" />

        <TextView
            android:id="@+id/text3"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:gravity="center"
            android:text="\n页卡3"
            android:textColor="#000000" />
    </LinearLayout>

    <ImageView
        android:id="@+id/cursor"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:scaleType="matrix"
        android:src="@drawable/icon_tab_page_bg" />

    <android.support.v4.view.ViewPager
        android:id="@+id/vPager"
        android:layout_width="wrap_content"
        android:layout_height="fill_parent"
        android:layout_gravity="center"
        android:layout_weight="1"
        android:background="#FFDFD7D7"
        android:flipInterval="30"
        android:persistentDrawingCache="animation" />

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="#FFDFD7D7"
    android:orientation="vertical" >
        <Button
        android:id="@+id/btn"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:gravity="center"
        android:text="点击我" />
</LinearLayout>