Android實現圖片文字輪播特效

本文實例講解了Android實現圖片文字輪播特效的詳細代碼，分享給大家供大家參考，具體內容如下

圖片輪播是類似知乎日報上的一個輪播效果，如下圖。

好了直接進入正題，首先是出示一下效果：

MainActivity：

import java.util.ArrayList; 
import java.util.List; 
import java.util.concurrent.Executors; 
import java.util.concurrent.ScheduledExecutorService; 
import java.util.concurrent.TimeUnit; 
 
import android.os.Bundle; 
import android.app.Activity; 
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.ViewGroup; 
import android.widget.ImageView; 
import android.widget.ImageView.ScaleType; 
import android.widget.LinearLayout; 
import android.widget.TextView; 
 
public class MainActivity extends Activity { 
 
  //viewpager 
  private ViewPager view_pager; 
  private LinearLayout ll_dotGroup; 
  private TextView newsTitle; 
  private int imgResIds[] = new int[]{R.drawable.a, R.drawable.b, 
      R.drawable.c, R.drawable.d, R.drawable.b}; 
  //存儲5張圖片 
  private String textview[]=new String[]{"12412515125","fawfafawf" 
      ,"13f1f12f211","1251f1f12","1t1f12f121"}; 
  //存儲5個目錄 
  private int curIndex = 0; 
  //用來記錄當前滾動的位置 
  PicsAdapter picsAdapter; 
 
  @Override 
  protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 
 
    setViewPager(); 
 
  } 
 
  private void setViewPager() { 
 
    newsTitle=(TextView)findViewById(R.id.NewsTitle); 
    view_pager = (ViewPager) findViewById(R.id.view_pager); 
    ll_dotGroup = (LinearLayout) findViewById(R.id.dotgroup); 
 
    picsAdapter = new PicsAdapter(); // 創建適配器 
    picsAdapter.setData(imgResIds); 
    view_pager.setAdapter(picsAdapter); // 設置適配器 
 
    view_pager.setOnPageChangeListener(new MyPageChangeListener()); //設置頁面切換監聽器 
 
    initPoints(imgResIds.length); // 初始化圖片小圓點 
    startAutoScroll(); // 開啟自動播放 
  } 
 
 
  // 初始化圖片輪播的小圓點和目錄 
  private void initPoints(int count) { 
    for (int i = 0; i < count; i++) { 
 
      ImageView iv = new ImageView(this); 
      LinearLayout.LayoutParams params = new LinearLayout.LayoutParams( 
          20, 20); 
      params.setMargins(0, 0, 20, 0); 
      iv.setLayoutParams(params); 
 
      iv.setImageResource(R.drawable.dot1); 
 
      ll_dotGroup.addView(iv); 
 
    } 
    ((ImageView) ll_dotGroup.getChildAt(curIndex)) 
        .setImageResource(R.drawable.dot2); 
 
    newsTitle.setText(textview[curIndex]); 
  } 
 
  // 自動播放 
  private void startAutoScroll() { 
    ScheduledExecutorService scheduledExecutorService = Executors 
        .newSingleThreadScheduledExecutor(); 
    // 每隔4秒鐘切換一張圖片 
    scheduledExecutorService.scheduleWithFixedDelay(new ViewPagerTask(), 5, 
        4, TimeUnit.SECONDS); 
  } 
 
  // 切換圖片任務 
  private class ViewPagerTask implements Runnable { 
    @Override 
    public void run() { 
 
      runOnUiThread(new Runnable() { 
        @Override 
        public void run() { 
          int count = picsAdapter.getCount(); 
          view_pager.setCurrentItem((curIndex + 1) % count); 
        } 
      }); 
    } 
  } 
 
  // 定義ViewPager控件頁面切換監聽器 
  class MyPageChangeListener implements OnPageChangeListener { 
 
    @Override 
    public void onPageScrolled(int position, float positionOffset, 
                  int positionOffsetPixels) { 
    } 
 
    @Override 
    public void onPageSelected(int position) { 
      ImageView imageView1 = (ImageView) ll_dotGroup.getChildAt(position); 
      ImageView imageView2 = (ImageView) ll_dotGroup.getChildAt(curIndex); 
      if (imageView1 != null) { 
        imageView1.setImageResource(R.drawable.dot2); 
      } 
      if (imageView2 != null) { 
        imageView2.setImageResource(R.drawable.dot1); 
      } 
      curIndex = position; 
      newsTitle.setText(textview[curIndex]); 
 
    } 
 
 
    boolean b = false; 
 
    @Override 
    public void onPageScrollStateChanged(int state) { 
      //這段代碼可不加，主要功能是實現切換到末尾後返回到第一張 
      switch (state) { 
        case 1:// 手勢滑動 
          b = false; 
          break; 
        case 2:// 界面切換中 
          b = true; 
          break; 
        case 0:// 滑動結束，即切換完畢或者加載完畢 
          // 當前為最後一張，此時從右向左滑，則切換到第一張 
          if (view_pager.getCurrentItem() == view_pager.getAdapter() 
              .getCount() - 1 && !b) { 
            view_pager.setCurrentItem(0); 
          } 
          // 當前為第一張，此時從左向右滑，則切換到最後一張 
          else if (view_pager.getCurrentItem() == 0 && !b) { 
            view_pager.setCurrentItem(view_pager.getAdapter() 
                .getCount() - 1); 
          } 
          break; 
 
        default: 
          break; 
      } 
    } 
  } 
 
  // 定義ViewPager控件適配器 
  class PicsAdapter extends PagerAdapter { 
 
    private List<ImageView> views = new ArrayList<ImageView>(); 
 
    @Override 
    public int getCount() { 
      if (views == null) { 
        return 0; 
      } 
      return views.size(); 
    } 
 
    public void setData(int[] imgResIds) { 
      for (int i = 0; i < imgResIds.length; i++) { 
        ImageView iv = new ImageView(MainActivity.this); 
        ViewGroup.LayoutParams params = new ViewGroup.LayoutParams( 
            ViewGroup.LayoutParams.MATCH_PARENT, 
            ViewGroup.LayoutParams.MATCH_PARENT); 
        iv.setLayoutParams(params); 
        iv.setScaleType(ScaleType.FIT_XY); 
        //設置ImageView的屬性 
        iv.setImageResource(imgResIds[i]); 
        views.add(iv); 
      } 
    } 
 
    public Object getItem(int position) { 
      if (position < getCount()) 
        return views.get(position); 
      return null; 
    } 
 
    @Override 
    public boolean isViewFromObject(View arg0, Object arg1) { 
      return arg0 == arg1; 
    } 
 
    @Override 
    public void destroyItem(View container, int position, Object object) { 
 
      if (position < views.size()) 
        ((ViewPager) container).removeView(views.get(position)); 
    } 
 
    @Override 
    public int getItemPosition(Object object) { 
      return views.indexOf(object); 
    } 
 
    @Override 
    public Object instantiateItem(View container, int position) { 
      if (position < views.size()) { 
        final ImageView imageView = views.get(position); 
        ((ViewPager) container).addView(imageView); 
        return views.get(position); 
      } 
      return null; 
    } 
 
  } 
 
} 

activity_main:

<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" > 
 
  <RelativeLayout 
    android:layout_width="match_parent" 
    android:layout_height="150dp" 
    android:layout_marginBottom="5dp" 
    android:orientation="vertical" > 
 
    <android.support.v4.view.ViewPager 
      android:id="@+id/view_pager" 
      android:layout_width="match_parent" 
      android:layout_height="match_parent" 
      android:layout_gravity="center" > 
    </android.support.v4.view.ViewPager> 
 
    <RelativeLayout 
      android:layout_width="match_parent" 
      android:layout_height="wrap_content" 
      android:layout_alignParentBottom="true" 
      android:background="@drawable/focus_bg" 
      > 
      <TextView 
        android:id="@+id/NewsTitle" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:text="我校交換生演講比賽奪冠 美國華盛本大學萬裡發來賀電" 
        android:paddingTop="10dp" 
        android:paddingBottom="8dp" 
        android:paddingLeft="10dp" 
        android:paddingRight="100dp" 
        android:textSize="15sp" 
        android:textColor="#fff"/> 
    <LinearLayout 
      android:id="@+id/dotgroup" 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:layout_alignParentRight="true" 
      android:paddingTop="23dp" 
      android:paddingRight="10dp" 
      android:gravity="center" 
      android:layout_marginBottom="15dp" 
      android:orientation="horizontal" > 
    </LinearLayout> 
  </RelativeLayout> 
  </RelativeLayout> 
 
</RelativeLayout>

 以上就是關於Android實現圖片文字輪播特效講解，希望對大家的學習有所幫助。