我已经写了一些listView活动，作为我自己的概念证明，我可以做到。现在，我无法将listView活动加载到具有多个选项卡的应用程序的单个选项卡中，从而允许滑动和选项卡选择以进行导航。当我尝试为它编写代码时，我收到错误“构造函数ListView_Adapter（MainActivity.DummySectionFragment）未定义”。我是初学者，过去几天我在这里非常努力。任何帮助表示赞赏。
TL; DR：我是n00b，我无法弄清楚这个问题。
我的自定义列表适配器
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;
public class CustomListViewAdapter extends ArrayAdapter<String> {
public CustomListViewAdapter (Context c) {
super(c, R.layout.list_cell);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = convertView;
ListView_Text holder = null;
if (row == null)
{
LayoutInflater inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
row = inflater.inflate(R.layout.list_cell, parent, false);
holder = new ListView_Text(row);
row.setTag(holder);
}
else
{
holder = (ListView_Text) row.getTag();
}
holder.populateFrom(getItem(position));
return row;
}
static class ListView_Text {
private TextView cell_name = null;
ListView_Text(View row) {
cell_name = (TextView) row.findViewById(R.id.list_cell_name);
}
void populateFrom(String index) {
cell_name.setText(index);
}
}
}
我的主要活动
import java.util.Locale;
import android.app.ActionBar;
import android.app.ActionBar.Tab;
import android.app.FragmentTransaction;
import com.example.twigglebeta2.ListView_Adapter;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.app.NavUtils;
import android.support.v4.view.ViewPager;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListView;
import android.widget.TextView;
public class MainActivity extends FragmentActivity implements ActionBar.TabListener {
private static ListView_Adapter listViewAdapter;
private ListView listView;
SectionsPagerAdapter mSectionsPagerAdapter;
ViewPager mViewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Set up the action bar.
final ActionBar actionBar = getActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
// Create adapter
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
// Set up the ViewPager with the sections adapter.
mViewPager = (ViewPager) findViewById(R.id.pager);
mViewPager.setAdapter(mSectionsPagerAdapter);
// Switch tab selection to match current page when swiped
mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
@Override
public void onPageSelected(int position) {
actionBar.setSelectedNavigationItem(position);
}
});
// Create a tab for each 'count' in the activity from getCount()
for (int i = 0; i < mSectionsPagerAdapter.getCount(); i++) {
Tab thisTab = actionBar.newTab();
thisTab.setText(mSectionsPagerAdapter.getPageTitle(i));
thisTab.setTabListener(this);
actionBar.addTab(thisTab);
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public void onTabSelected(ActionBar.Tab tab,FragmentTransaction fragmentTransaction) {
// When the given tab is selected, switch to the corresponding page in
// the ViewPager.
mViewPager.setCurrentItem(tab.getPosition());
}
@Override
public void onTabUnselected(ActionBar.Tab tab,FragmentTransaction fragmentTransaction) {
}
@Override
public void onTabReselected(ActionBar.Tab tab,FragmentTransaction fragmentTransaction) {
}
/**
* A {@link FragmentPagerAdapter} that returns a fragment corresponding to
* one of the sections/tabs/pages.
*/
public class SectionsPagerAdapter extends FragmentPagerAdapter {
public SectionsPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
// getItem is called to instantiate the fragment for the given page.
// Return a DummySectionFragment (defined as a static inner class
// below) with the page number as its lone argument.
Fragment fragment = new DummySectionFragment();
Bundle args = new Bundle();
args.putInt(DummySectionFragment.ARG_SECTION_NUMBER, position + 1);
fragment.setArguments(args);
return fragment;
}
@Override
public int getCount() {
// Show 3 total pages.
return 3;
}
@Override
public CharSequence getPageTitle(int position) {
Locale l = Locale.getDefault();
switch (position) {
case 0:
return getString(R.string.title_section1).toUpperCase(l);
case 1:
return getString(R.string.title_section2).toUpperCase(l);
case 2:
return getString(R.string.title_section3).toUpperCase(l);
}
return null;
}
}
/**
* A dummy fragment representing a section of the app, but that simply
* displays dummy text.
*/
public static class DummySectionFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
public static final String ARG_SECTION_NUMBER = "section_number";
public DummySectionFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main_dummy,container, false);
switch(getArguments().getInt(ARG_SECTION_NUMBER)){
case 1:
//The constructor ListView_Adapter(MainActivity.DummySectionFragment) is undefined
listViewAdapter = new ListView_Adapter(this);
ListView listView = (ListView) rootView.findViewById(R.id.listView1);
for (int i=0;i<20;i++)
{
listViewAdapter.add("this Index : "+i);
}
return listView;
}
TextView dummyTextView = (TextView) rootView.findViewById(R.id.section_label);
dummyTextView.setText(Integer.toString(getArguments().getInt(ARG_SECTION_NUMBER)));
return rootView;
}
}
}
答案 0 :(得分：19)
而不是listViewAdapter = new ListView_Adapter(this);，您应该尝试listViewAdapter = new ListView_Adapter(getActivity().getBaseContext());
问题是您正在将Fragment传递给构造函数，而不是Activity上下文。