在我的 MainActivity 中，我派生了一个数据数组列表。这里的技巧是，我试图根据所选的选项卡以不同的方式在 ListView 中重新排列此数据集合(按字母顺序、按时间顺序等)，我有执行此操作的代码。
以下是我的主要 Activity 。
public class MainActivity extends AppCompatActivity {
private SectionsPagerAdapter mSectionsPagerAdapter;
private ViewPager mViewPager;
private FloatingActionButton fab;
private final int PICK = 1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
fp_get_Android_Contacts();
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
// Set up the ViewPager with the sections adapter.
mViewPager = (ViewPager) findViewById(R.id.container);
mViewPager.setAdapter(mSectionsPagerAdapter);
TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(mViewPager);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(Intent.ACTION_PICK,
ContactsContract.Contacts.CONTENT_URI);
// calling OnActivityResult with intenet And Some conatct for Identifie
startActivityForResult(intent, PICK);
}
});
}
public class Android_Contact {
public String android_contact_Name = "";
public String android_contact_TelefonNr = "";
public int android_contact_ID = 0;
}
public void fp_get_Android_Contacts() {
ArrayList<Android_Contact> arrayListAndroidContacts = new ArrayList<Android_Contact>();
Cursor cursor_Android_Contacts = null;
ContentResolver contentResolver = getContentResolver();
try {
cursor_Android_Contacts = contentResolver.query(ContactsContract.Contacts.CONTENT_URI, null, null, null, null);
} catch (
Exception ex
)
{
Log.e("Error on contact", ex.getMessage());
}
if (cursor_Android_Contacts.getCount() > 0)
{
while (cursor_Android_Contacts.moveToNext()) {
Android_Contact android_contact = new Android_Contact();
String contact_id = cursor_Android_Contacts.getString(cursor_Android_Contacts.getColumnIndex(ContactsContract.Contacts._ID));
String contact_display_name = cursor_Android_Contacts.getString(cursor_Android_Contacts.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));
android_contact.android_contact_Name = contact_display_name;
int hasPhoneNumber = Integer.parseInt(cursor_Android_Contacts.getString(cursor_Android_Contacts.getColumnIndex(ContactsContract.Contacts.HAS_PHONE_NUMBER)));
if (hasPhoneNumber > 0) {
Cursor phoneCursor = contentResolver.query(
ContactsContract.CommonDataKinds.Phone.CONTENT_URI
, null
, ContactsContract.CommonDataKinds.Phone.CONTACT_ID + " = ?"
, new String[]{contact_id}
, null);
while (phoneCursor.moveToNext()) {
String phoneNumber = phoneCursor.getString(phoneCursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
android_contact.android_contact_TelefonNr = phoneNumber;
}
phoneCursor.close();
}
arrayListAndroidContacts.add(android_contact);
}
Collections.reverse(arrayListAndroidContacts);
ListView listView_Android_Contacts = (ListView) findViewById(R.id.listview_Android_Contacts);
Adapter_for_Android_Contacts adapter = new Adapter_for_Android_Contacts(this, arrayListAndroidContacts);
listView_Android_Contacts.setAdapter(adapter);
}
}
public class Adapter_for_Android_Contacts extends BaseAdapter {
Context mContext;
List<Android_Contact> mList_Android_Contacts;
public Adapter_for_Android_Contacts(Context mContext, List<Android_Contact> mContact) {
this.mContext = mContext;
this.mList_Android_Contacts = mContact;
}
public int getCount() {
return mList_Android_Contacts.size();
}
public Object getItem(int position) {
return mList_Android_Contacts.get(position);
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
View view = View.inflate(mContext, R.layout.contactlist_android_items, null);
TextView textview_contact_Name = (TextView) view.findViewById(R.id.textview_android_contact_name);
textview_contact_Name.setText(mList_Android_Contacts.get(position).android_contact_Name);
view.setTag(mList_Android_Contacts.get(position).android_contact_Name);
return view;
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
public class SectionsPagerAdapter extends FragmentPagerAdapter {
public SectionsPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
switch (position) {
case 0:
Tab2AZ tab2 = new Tab2AZ();
return tab2;
case 1:
Tab1Recents tab1 = new Tab1Recents();
return tab1;
case 2:
Tab3Location tab3 = new Tab3Location();
return tab3;
case 3:
Tab4Groups tab4 = new Tab4Groups();
return tab4;
default:
return null;
}
}
@Override
public int getCount() {
// Show 3 total pages.
return 4;
}
@Override
public CharSequence getPageTitle(int position) {
switch (position) {
case 0:
return "A-Z";
case 1:
return "RECENT";
case 2:
return "LOCATION";
case 3:
return "TAGS";
}
return null;
}
}
}
为了节省时间，fp_get_Android_Contacts() 方法会获取数组列表，然后使用适配器将内容放入主 Activity xml 中的 ListView 中。结果是所有选项卡在视觉上显示相同的 View 。 (因为 MainActivity 的 ListView 覆盖了 fragment 的 ListView )我实际上只是想将从 fp_get_Android_Contacts() 方法检索到的内容一次显示在一个 fragment 上。我研究过使用 bundle 、可分包、 Intent 和最近的接口(interface)，但考虑到我的经验水平，成功的实现可能很难实现。希望有一种具体的方法而不是引用来阅读一些东西，因为我已经做了很多研究并尝试了很多事情。
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
View rootView = inflater.inflate(R.layout.tab1_recent, container, false);
return rootView;
}
}
最佳答案
创建接口(interface)
public interface FragmentListener {
void setArrayListAndroidContacts(List<Android_Contact> contacts);
List<Android_Contact> getArrayListAndroidContacts();
}
让你的MainActivity实现这个接口(interface)
public class MainActivity extends AppCompatActivity implements FragmentListener {
//global field
private List<Android_Contact> arrayListAndroidContacts;
...
//your code
...
//override methods of interface
@Override
void setArrayListAndroidContacts(List<Android_Contact> contacts){
this.arrayListAndroidContacts = contacts;
}
@Override
List<Android_Contact> getArrayListAndroidContacts(){
return this.arrayListAndroidContacts;
}
你的 fragment
public class YourFragment extends Fragment{
private FragmentListener mListener;
...
//in onCreateView
//this will give you list
mListener.getArrayListAndroidContacts();
....
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof FragmentListener) {
mListener = (FragmentListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement FragmentListener");
}
}
}
另一种方法是在 MainActivity 中创建 arrayListAndroidContacts 的公共(public) getter setter，并在 fragment 中使用 (MainActivity getActivity()).getArrayListAndroidContacts() 来获取列表。由于可重用性，我更喜欢接口(interface)方法。
如果您想通过过滤器选择(按 alpha、chrono 排序)重新排列数据而不更改任何 View ，为什么还要创建 viewpager、fragments。
只需在 float 菜单/工具栏侧边菜单、回收器 View (任何 ListView )中添加过滤器菜单操作，并在 Mainactivity 中为其添加自定义适配器。根据过滤器选择重新排序您的联系人列表，notifydatasetchanged 将完成您的所有工作。
如果您希望在单个屏幕中显示联系人类别(如 Collection 夹、业务等)，请使用选项卡。
建议:- 请将您的自定义 BaseAdapter 代码与 MainActivity 分开，以便更好地维护源代码。
关于java - Android 在使用 Activity、Fragment、Listview 和 Tabs 时传递数据，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/41967108/