Question

我正在尝试分享我在viewpager上点击按钮时显示的文字，但是它正在从下一页发送文本。就像在viewpager的第一页上一样，它显示了＆＃39; 0＆＃39;当我将它分享到什么应用程序或短信时，它发送文本＆＃39; 1＆＃39;即字符串数组中的下一个文本这是我的代码。

SampleFragmant.java
public class SampleFragmant extends Fragment {
    ViewPager viewPager;
    SampleAdapter adapter;
    ImageView shareButton, saveButton;

@Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {

        View rootView = inflater.inflate(R.layout.sample,
                container, false);

        viewPager = (ViewPager) rootView
                .findViewById(R.id.view_pager);
shareButton = (ImageView) rootView.findViewById(R.id.shareButton);       
shareButton.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
Intent sharingIntent = new Intent(
                        android.content.Intent.ACTION_SEND);
                sharingIntent.setType("text/plain");

                String shareBody = adapter.textposition;
                sharingIntent.putExtra(android.content.Intent.EXTRA_SUBJECT,
                        "Test Application:");
                sharingIntent.putExtra(android.content.Intent.EXTRA_TEXT,
                        shareBody);
                startActivity(Intent.createChooser(sharingIntent, "Share via"));

            }
        });

        adapter = new SampleAdapter(getActivity());

        viewPager.setAdapter(adapter);
        return rootView;
    }
}

SampleAdapter.java

public class SampleAdapter extends PagerAdapter {
    Context context;
    public String textposition;
    private String[] textToDisplay = new String[] {
            "0","1","2","3","4","5","6"};
@Override
    public int getCount() {
        // TODO Auto-generated method stub
        return textToDisplay.length;
    }

    @Override
    public boolean isViewFromObject(View view, Object object) {
        // TODO Auto-generated method stub
        return view == ((TextView) object);
    }
@Override
    public Object instantiateItem(View container, int position) {
        // TODO Auto-generated method stub

        TextView textView = new TextView(context);
        textView.setText(textToDisplay[position]);
         textposition= textToDisplay[position];
        textView.setTextSize(16);
        textView.setTypeface(null, Typeface.BOLD_ITALIC);
        textView.setGravity(Gravity.CENTER);
((ViewPager) container).addView(textView, 0);
        return textView;
    }
    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        ((ViewPager) container).removeView((TextView) object);
    }
}

Answer 1

默认情况下，ViewPager会一次创建多个视图。例如，如果向用户显示位置为5的视图，则会创建位置为4,5和6的视图。这是平滑过渡动画所需，并由setOffscreenPageLimit(int limit)控制（默认限制为1）。因此，它将通过调用instantiateItem方法实例化这些位置的视图。这就是为什么假设您在instantiateItem中获得的位置是向用户显示的视图的位置是不正确的。

您应该使用ViewPager.OnPageChangeListener的onPageSelected(int position)来确定当前视图的位置。

Android无法从viewpager共享正确的文本

1 个答案: