对话框显示绝对没有内容？

Question

基本上我只想在对话框中有一个视图寻呼机。就是这样，但由于某种原因，对话框为空？

这是我的对话代码：

final Dialog dialog = new Dialog(this);
    dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
    dialog.setContentView(R.layout.voicedialog);
    dialog.setCanceledOnTouchOutside(false);

    MyPageAdapter adapter = new MyPageAdapter();
    ViewPager pager = (ViewPager) dialog.findViewById(R.id.viewpager);
    pager.setOffscreenPageLimit(3);
    pager.setAdapter(adapter);

    dialog.show();

这里是对话框布局，voicedialog，只是一个空视图寻呼机：

<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"

    />

这是适配器：

public class MyPageAdapter extends PagerAdapter {
    public Object instantiateItem(ViewGroup collection, int position) {

        int resId = 0;
        switch (position) {
            case 0:
                resId = R.id.voice1;
                break;
            case 1:
                resId = R.id.voice2;
                break;
            case 2:
                resId = R.id.voice3;
                break;
        }
        return collection.findViewById(resId);
    }

    @Override
    public int getCount() {
        return 3;
    }

    @Override
    public boolean isViewFromObject(View arg0, Object arg1) {
        return arg0 == arg1;
    }

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

如此简单，对吗？但是，当我运行此代码时，我得到一个 EMPTY 对话框：

相反，它应该显示我可以滑动浏览的三个布局（voice1、voice2、voice3）！这些布局只有一个文本视图，但没有显示。

请告诉我如何实现这一点。令人沮丧——我花了将近 6 个小时试图解决这个问题 :)

Answer 1

首先在您的 PagerAapter 中通过这样的构造函数获取上下文、列表和 LayoutInflator

Context mContext;
LayoutInflater mLayoutInflater;
List<String> mList;

public MyPageAdapter(Context context, List<String> list) {
    mContext = context;
    mList = list;
    mLayoutInflater = (LayoutInflater)mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

然后在 getItemCount 方法中返回您的列表大小

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

然后

public Object instantiateItem(ViewGroup collection, int position) {
     View view = inflater.inflate(R.layout.your_layout, null);
     TextView textView = (TextView) layout.findViewById(R.id.text_view);
     textView.setText(mList.get(postiion);
     collection.addView(view);
     return view;
}

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

Answer 2

按照以下步骤在对话框中打开 viewPager

1 - 单击按钮时，打开扩展 DialogFragment 的片段，在该 DialogFragment 中声明并初始化 viewpager

2 - 接下来创建一个扩展来自 android.support.v13.app.FragmentPagerAdapter 的 FragmentPagerAdapter 的适配器，对于这个适配器，您必须使用这个 gradle：- compile 'com.android.support:support-v13:+'

单击按钮时打开 DialogFragment

private void ShowDialog() {
    DialogViewPager dialogViewPager = new DialogViewPager();
    dialogViewPager.show(getFragmentManager(),"DialogViewPager");
}

对话框片段

public class DialogViewPager extends DialogFragment {

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.dialog_layout, container);
    getDialog().getWindow().requestFeature(Window.FEATURE_NO_TITLE);
    return view;
}

@Override
public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);
    ViewPager viewPager = (ViewPager) getView().findViewById(R.id.view_pager);
    viewPager.setAdapter(new MyViewPagerAdapter(getChildFragmentManager()));
}

class MyViewPagerAdapter extends FragmentPagerAdapter {

    public MyViewPagerAdapter(FragmentManager fm) {
        super(fm);
    }

    @Override
    public Fragment getItem(int position) {
        switch (position) {
            case 0:
                return FirstFragment.newInstance();
            case 1:
                return SecondFragment.newInstance();
            default:
                return null;
        }
    }

    @Override
    public int getCount() {
        return 2;
    }
  }
}