Question

我需要将来自不同XML的一些布局组显示为ViewPager的项目。我创建了2种不同的布局。我想使用card.xml 1次，并使用其他多个。当我点击card.xml的视图时，我将编写一个代码来添加一个新的credit_cards.xml视图。在这里，我添加前两个布局，我可以在viewpager上看到它们。我正在尝试手动添加新视图，但我遇到了错误。这是我第一次使用viewpager，所以我不确定问题出在哪里。

这是我的活动。

public class MainActivity extends AppCompatActivity {
   final Context mContext = this;
   public List<View> mList = new ArrayList<>();
   ViewPager pager;
   ViewPagerAdapter adapter;
   LinearLayout first, second;


   @Override
   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);

       View view =    LayoutInflater.from(getApplication()).inflate(R.layout.credit_cards, null);

       first = (LinearLayout) view.findViewById(R.id.addNewCard);
       second = (LinearLayout) view.findViewById(R.id.creditCard);
       pager = (ViewPager) findViewById(R.id.viewpager);

       mList.add(first);
       adapter = new ViewPagerAdapter(mContext, mList);
       adapter.addView(second,0);
       pager.setAdapter(adapter);
       pager.setPageTransformer(true, new ZoomOutPageTransformer());
   }
}

这是ViewPager。

<?xml version="1.0" encoding="utf-8"?>
<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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.seray.myapplication.MainActivity">

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="0.5"
        android:layout_marginBottom="1sp">

        <android.support.v4.view.ViewPager
            android:id="@+id/viewpager"
            xmlns:android="http://schemas.android.com/apk/res/android"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:background="#FFFFFF"/>

    </RelativeLayout>

</RelativeLayout>

适配器。

public class ViewPagerAdapter extends PagerAdapter {

    public List<View> mList;
    private final Context mContext;
    LinearLayout first, second;
    View mPrimaryItem;

    public ViewPagerAdapter(Context mContext, List<View> mList){
        this.mContext = mContext;
        this.mList = mList;
    }

    @Override
    public int getItemPosition(Object object) {
        if (mList.contains((View) object)) {
            return mList.indexOf((View) object);
        } else {
            return POSITION_NONE;
        }
     }

     @Override
     public void setPrimaryItem(ViewGroup container, int position,
                           Object object) {
        super.setPrimaryItem(container, position, object);
        mPrimaryItem = (View) object;
     }

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

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

    public void addView(View view, int index) {
        mList.add(index, view);
        notifyDataSetChanged();
    }   

    public void removeView(int index) {
        mList.remove(index);
        notifyDataSetChanged();
    }

    @Override
    public Object instantiateItem(ViewGroup container, int position) {
        View v = mList.get(position);

        ((ViewPager)container).addView(v);
        return v;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        container.removeView((View) object);
    }
}

我无法将从不同XML调用的新项添加到ViewPager

0 个答案: