以前的数据显示在ViewPager Android上

Question

在我的应用中，我有ViewPager CirclePageIndicator并且它正在运行。它在One pager中显示两个项目。当我滑动到另一个寻呼机时，它显示前一个项目。我不想要它。我希望一次刷两件物品。不会显示已在寻呼机上显示的上一个。

这是我之前的问题，它与此有关。 Show two item in ViewPager android

  

目前正在工作   ItemA，ItemB | ItemB，ItemC | ItemC，ItemD |

     

我想要像      ItemA，ItemB | ItemC，ItemD | ItemE，ItemF |

这是我用来在一个寻呼机中显示两个项目的代码。

@Override
public float getPageWidth(int position) {
    return(0.5f);
}

Adapter.class

public class ViewPagerAdapter extends PagerAdapter {
    // Declare Variables
    Context context;
    String[] domain;
    String[] title;
    int[] flag;
    LayoutInflater inflater;

    public ViewPagerAdapter(Context context, String[] domain,
                            String[] title, int[] flag) {
        this.context = context;
        this.domain = domain;
        this.title = title;
        this.flag = flag;
    }

 @Override
public int getCount() {
    return (int) Math.ceil((double)title.length/2);
}

    @Override
    public boolean isViewFromObject(View view, Object object) {
        return view == ((RelativeLayout) object);
    }



@Override
public Object instantiateItem(ViewGroup container, int position) {

    inflater = (LayoutInflater) context
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View pageView = inflater.inflate(R.layout.related_article_item_page, container,
            false);

    // Locate the TextViews in viewpager_item.xml
    View itemView1 = pageView.findViewById(R.id.article_1);
    View itemView2 = pageView.findViewById(R.id.article_2);

    configureItemView(itemView1, calculateFirstItemDataPosition(position));
    configureItemView(itemView2, calculateSecondItemDataPosition(position));

    return pageView;
}

public int calculateFirstItemDataPosition(int position){
    return position * 2;
}

public int calculateSecondItemDataPosition(int position){
    return position * 2 + 1;
}

public void configureItemView(View view,int position){
    inflater = (LayoutInflater) context
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    View ConfigItemView = inflater.inflate(R.layout.related_article_item, null);

    // Locate the TextViews in viewpager_item.xml
    final Button btnSave = (Button) ConfigItemView.findViewById(R.id.btn_save);
    final Button btnLike = (Button) ConfigItemView.findViewById(R.id.btn_like);
    final TextView tv_domain = (TextView) ConfigItemView.findViewById(R.id.domain_text);
    TextView tv_title = (TextView) ConfigItemView.findViewById(R.id.title_text);
    ResizableImageView imageView = (ResizableImageView) ConfigItemView.findViewById(R.id.imageViewDynamic);
    final ProgressBar progressBar = (ProgressBar) ConfigItemView.findViewById(R.id.loading);

    // Capture position and set to the TextViews
    tv_domain.setText(domain[position]);
    tv_title.setText(title[position]);

    // Locate the ImageView in viewpager_item.xml
    imageView.setImageResource(flag[position]);

    // Add viewpager_item.xml to ViewPager
}



    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        // Remove viewpager_item.xml from ViewPager
        //((ViewPager) container).removeView((RelativeLayout) object);

    }


}

活动

    public class TestingActivity extends ActionBarActivity {
        // Declare Variables
        ViewPager viewPager;
        PagerAdapter adapter;
        String[] title;
        String[] domain;
        int[] flag;
        CirclePageIndicator mIndicator;

        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            // Get the view from viewpager_main.xml
            setContentView(R.layout.viewpager_main);

            title = new String[]{"Canada", "Thailand", "United States United StatesUnited StatesUnited States United States United States United States United States United States United States United States United States United States United States United States United States ",
                "Indonesia", "Brazil", "Thailand", "Nigeria", "Singapore",
                "RussiaRussiaRussiaRussiaRussiaRussiaRussiaRussia", "Japan"};

            domain = new String[]{"text1", "text1",
                "text1", "text1", "text1", "text1",
                "text1", "text1", "text1", "text1"};

            flag = new int[]{R.drawable.arsenal, R.drawable.aston_villa,
                R.drawable.manchester_city, R.drawable.liverpool,
                R.drawable.chelsea, R.drawable.manchester_united, R.drawable.swansea,
                R.drawable.liverpool, R.drawable.west_brom, R.drawable.west_ham};

            // Locate the ViewPager in viewpager_main.xml
            viewPagerRelated = (ViewPager) findViewById(R.id.pager2);
            // Pass results to ViewPagerAdapter Class
            adapter = new ViewPagerAdapter(ArticleViewActivityV2.this, domain,
                title, flag);
            // Binds the Adapter to the ViewPager
            viewPagerRelated.setAdapter(adapter);
            // viewPagerRelated.setPageMargin(3);
            // ViewPager Indicator
            mIndicator = (CirclePageIndicator) findViewById(R.id.indicator_pager);
            mIndicator.setViewPager(viewPagerRelated);    
        }
    }

日志文件

java.lang.ArrayIndexOutOfBoundsException: length=9; index=9
        at com.sample.news.adapters.ViewPagerAdapter.configureItemView(ViewPagerAdapter.java:94)
        at com.sample.news.adapters.ViewPagerAdapter.instantiateItem(ViewPagerAdapter.java:64)
        at android.support.v4.view.ViewPager.addNewItem(ViewPager.java:869)
        at android.support.v4.view.ViewPager.populate(ViewPager.java:1085)
        at android.support.v4.view.ViewPager.populate(ViewPager.java:951)
        at android.support.v4.view.ViewPager.onTouchEvent(ViewPager.java:2041)
        at android.view.View.dispatchTouchEvent(View.java:7717)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2244)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1979)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2250)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1951)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2250)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1951)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2250)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1951)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2250)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1951)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2250)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1951)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2250)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1951)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2250)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1951)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2250)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1951)
        at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:2087)
        at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1532)
        at android.app.Activity.dispatchTouchEvent(Activity.java:2467)
        at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:2035)
        at android.view.View.dispatchPointerEvent(View.java:7897)
        at android.view.ViewRootImpl$ViewPostImeInputStage.processPointerEvent(ViewRootImpl.java:4005)
        at android.view.ViewRootImpl$ViewPostImeInputStage.onProcess(ViewRootImpl.java:3884)
        at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3445)
        at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3495)
        at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3464)
        at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:3571)
        at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3472)
        at android.view.ViewRootImpl$AsyncInputStage.apply(ViewRootImpl.java:3628)
        at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3445)
        at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3495)
        at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3464)
        at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3472)
        at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3445)
        at android.view.ViewRootImpl.deliverInputEvent(ViewRootImpl.java:5653)
        at android.view.ViewRootImpl.doProcessInputEvents(ViewRootImpl.java:5633)
        at android.view.ViewRootImpl.enqueueInputEvent(ViewRootImpl.java:5604)
        at android.view.ViewRootImpl$WindowInputEventReceiver.onInputEvent(ViewRootImpl.java:5733)
        at android.view.InputEventReceiver.dispatchInputEvent(InputEventReceiver.java:185)
        at android.os.MessageQueue.nativePollOnce(Native Method)
        at android.os.MessageQueue.next(MessageQueue.java:138)
        at android.os.Looper.loop(Looper.java:123)
        at android.app.ActivityThread.main(ActivityThread.java:5050)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect

由于

Answer 1

我已经研究过ViewPager实现。滚动结束时方法ViewPager.determineTargetPage(int, float, int, int)确定目标页面，因为我看不到它的改变。

为了完成这项工作，我建议你一个解决方法并创建一个页面，里面有2个水平视图。在这种情况下，你应该删除

@Override
public float getPageWidth(int position) {
    return(0.5f);
}

修改

要使其工作，请添加新布局xml related_article_item_page.xml：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
          android:orientation="horizontal"
          android:layout_width="match_parent"
          android:layout_height="match_parent">

    <include
        layout="@layout/related_article_item"
        android:id="@+id/article_1"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="1"/>

    <include
        layout="@layout/related_article_item"
        android:id="@+id/article_2"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="1"/>
</LinearLayout>

然后更改您的ViewPagerAdapter.instatiateItem(ViewGroup, int)方法：

inflater = ...
View pageView = infalter.inflate(R.layout.related_article_item_page, container, false);

View itemView1 = pageView.findViewById(R.id.article_1);
View itemView2 = pageView.findViewById(R.id.article_2);

configureItemView(itemView1, calculateFirstItemDataPosition(position));
configureItemView(itemView2, calculateSecondItemDataPosition(position));

((ViewPager) container).addView(pageView);
return pageView;

{p}在configureItemView(View, int)中您应该设置itemView视图数据，在calculateFirstItemDataPosition(int) calculateSecondItemDataPosition(int)中，您应该计算当前适配器位置的数据位置。还记得改变getCount()方法 - 现在它会小2倍