它下面加圆点或者文字描述,其实是ViewPager和textvIEW等等布局在一个文件里面,其它布局通过监听viewPager的变化来动态改变自己而已,就是如此,一点也不神奇。
package com.example.listviewdemo; import android.app.Activity; import android.os.Bundle; import android.support.v4.view.PagerAdapter; import android.support.v4.view.ViewPager; import android.support.v4.view.ViewPager.OnPageChangeListener; import android.view.View; import android.view.View.OnClickListener; import android.view.ViewGroup; import android.widget.ImageView; import android.widget.ImageView.ScaleType; import android.widget.LinearLayout; /** *http://blog.csdn.net/qinyuanpei/article/details/17186319 *这有几篇文章 * *其实,下面的几个圆点是通过我们相对布局来弄上的,与本身的ViewPager并没有太大关系。 */ public class BannerActivity extends Activity implements OnClickListener { ViewPager mViewPager ; PagerAdapter mPagerAdapter ; private int[] draws = new int[]{R.drawable.bg,R.drawable.empty_paper_tape, R.drawable.login_warring_pic,R.drawable.share_tellfriends_bg,R.drawable.splash_bg}; //记录当前选中位置 private int currentIndex; //底部小图片 private ImageView[] dots ; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.banner); mViewPager = (ViewPager)findViewById(R.id.banner); initAdapter(); mViewPager.setAdapter(mPagerAdapter); initListener(); //初始化底部小点 initDots(); } private void initDots(){ dots = new ImageView[draws.length]; LinearLayout ll = (LinearLayout)findViewById(R.id.ll); for (int i = 0; i < draws.length; i++) { dots[i] = (ImageView)ll.getChildAt(i); dots[i].setEnabled(true); dots[i].setOnClickListener(this); dots[i].setTag(i);//设置位置tag,方便取出与当前位置对应 } currentIndex = 0; dots[currentIndex].setEnabled(false); } private void initAdapter(){ mPagerAdapter = new PagerAdapter() { @Override public Object instantiateItem(ViewGroup container, int position) { ImageView imageView = new ImageView(BannerActivity.this); imageView.setScaleType(ScaleType.FIT_XY); imageView.setImageResource(draws[position]); container.addView(imageView); return imageView; } @Override public void destroyItem(ViewGroup container, int position, Object object) { ImageView imageView = new ImageView(BannerActivity.this); imageView.setScaleType(ScaleType.FIT_XY); imageView.setImageResource(draws[position]); container.removeView(imageView); } @Override public boolean isViewFromObject(View arg0, Object arg1) { return arg0 == (View)arg1; } @Override public int getCount() { return draws == null ? 0 : draws.length;//因为会有一个左右尽头的数据 } }; } private void initListener(){ mViewPager.setOnPageChangeListener(new OnPageChangeListener() { @Override public void onPageSelected(int pos) { setCurDot(pos); } @Override public void onPageScrolled(int arg0, float arg1, int arg2) { } @Override public void onPageScrollStateChanged(int arg0) { } }); } private void setCurDot(int positon){ if (positon < 0 || positon > draws.length - 1 || currentIndex == positon) { return; } dots[positon] .setEnabled(false); dots[currentIndex].setEnabled(true); currentIndex = positon; } private void setCurView(int position){ if (position < 0 || position >= draws.length) { return; } mViewPager.setCurrentItem(position); } @Override public void onClick(View v) { int pos = (Integer)v.getTag(); setCurDot(pos); setCurView(pos); } }
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" > <android.support.v4.view.ViewPager android:id="@+id/banner" android:layout_width="match_parent" android:layout_height="match_parent" android:fadingEdge="none"/> <LinearLayout android:id="@+id/ll" android:orientation="horizontal" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginBottom="24.0dip" android:layout_alignParentBottom="true" android:layout_centerHorizontal="true"> <ImageView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center_vertical" android:clickable="true" android:padding="15.0dip" android:src="@drawable/dot" /> <ImageView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center_vertical" android:clickable="true" android:padding="15.0dip" android:src="@drawable/dot" /> <ImageView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center_vertical" android:clickable="true" android:padding="15.0dip" android:src="@drawable/dot" /> <ImageView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center_vertical" android:clickable="true" android:padding="15.0dip" android:src="@drawable/dot" /> <ImageView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center_vertical" android:clickable="true" android:padding="15.0dip" android:src="@drawable/dot" /> </LinearLayout> </RelativeLayout><?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" android:innerRadiusRatio="3" android:shape="ring" android:thickness="10dp" android:useLevel="false" > <solid android:color="#FF0000" /> <size android:height="10dp" android:width="10dp" /> </shape>
<?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" android:innerRadiusRatio="3" android:shape="ring" android:thickness="10dp" android:useLevel="false" > <solid android:color="#0000FF" /> <size android:height="10dp" android:width="10dp" /> </shape>
<?xml version="1.0" encoding="utf-8"?> <selector xmlns:android="http://schemas.android.com/apk/res/android" > <item android:state_enabled="true" android:drawable="@drawable/circlewhite"></item> <item android:state_enabled="false" android:drawable="@drawable/circleblack"></item> </selector>