我有两个片段并希望将它们显示为标签视图。但是不知道在下面的代码中添加这些片段的位置。这些是在android studio项目中选择“标签式活动”时的代码。
public class MainActivity extends AppCompatActivity {
/**
* The {@link android.support.v4.view.PagerAdapter} that will provide
* fragments for each of the sections. We use a
* {@link FragmentPagerAdapter} derivative, which will keep every
* loaded fragment in memory. If this becomes too memory intensive, it
* may be best to switch to a
* {@link android.support.v4.app.FragmentStatePagerAdapter}.
*/
private SectionsPagerAdapter mSectionsPagerAdapter;
/**
* The {@link ViewPager} that will host the section contents.
*/
private ViewPager mViewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
// Create the adapter that will return a fragment for each of the three
// primary sections of the activity.
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
// Set up the ViewPager with the sections adapter.
mViewPager = (ViewPager) findViewById(R.id.container);
mViewPager.setAdapter(mSectionsPagerAdapter);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}
@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);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
private static final String ARG_SECTION_NUMBER = "section_number";
public PlaceholderFragment() {
}
/**
* Returns a new instance of this fragment for the given section
* number.
*/
public static PlaceholderFragment newInstance(int sectionNumber) {
PlaceholderFragment fragment = new PlaceholderFragment();
Bundle args = new Bundle();
args.putInt(ARG_SECTION_NUMBER, sectionNumber);
fragment.setArguments(args);
return fragment;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
TextView textView = (TextView) rootView.findViewById(R.id.section_label);
textView.setText(getString(R.string.section_format, getArguments().getInt(ARG_SECTION_NUMBER)));
return rootView;
}
}
/**
* 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 PlaceholderFragment (defined as a static inner class below).
return PlaceholderFragment.newInstance(position + 1);
}
@Override
public int getCount() {
// Show 3 total pages.
return 2;
}
@Override
public CharSequence getPageTitle(int position) {
switch (position) {
case 0:
return "Demo";
case 1:
return "SECTION 2";
}
return null;
}
}
}
片段类
public class Fragment1 extends Fragment {
public static Fragment1 newInstance() {
Fragment1 fragment = (Fragment1) new Fragment();
return fragment;
}
public Fragment1() {
}
Button ClickMe;
TextView tv;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment1, container, false);
ClickMe = (Button) rootView.findViewById(R.id.button);
tv = (TextView) rootView.findViewById(R.id.textView2);
ClickMe.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if(tv.getText().toString().contains("Hello")){
tv.setText("Hi");
}else tv.setText("Hello");
}
});
return rootView;
}
} //这是我们的Fragment1类
的结尾答案 0 :(得分：2)
这是您需要将片段分别放到特定选项卡的位置。
@Override
public Fragment getItem(int position) {
// getItem is called to instantiate the fragment for the given page.
// Return a PlaceholderFragment (defined as a static inner class below).
return PlaceholderFragment.newInstance(position + 1);
}
对选择的位置使用switch case语句并在选项卡中获取片段。
switch (position) {
case 0:
// first fragment activity
return new firstfragment();
case 1:
// second fragment activity
return new secondFragment();
case 2:
// third fragment activity
return new thirdFragment();
}
return null;
}
答案 1 :(得分：0)
public Fragment getItem(int position) {
// getItem is called to instantiate the fragment for the given page.
// Return a PlaceholderFragment (defined as a static inner class below).
switch (position) {
case 0:
Fragment1 tab1 = new Fragment1();
return tab1;
case 1:
Fragment2 tab2 = new Fragment2();
return tab2;
// return PlaceholderFragment.newInstance(position + 1);
}
return null;
}
刚刚更改了上面这样的代码，并在Fragment1中扩展了公共类 Fragment1扩展了android.support.v4.app.Fragment
答案 2 :(得分：0)
首先，您必须使用getCount()方法指定要使用的标签数：
@Override
public int getCount() {
int numberOfTabs = 3;
return numberOfTabs;
}
然后，您必须创建自己的片段，然后将其添加到getItem(int position)方法中，如下所示：
@Override
public Fragment getItem(int position)
switch(position){
case 0:
return new YourFirstFragment();
case 1:
return new YourSecondFragment();
case 2:
return new YourThirdFragment();
default:
return new SomeFragment();
}
}
然后，您将使用getPageTitle(int position)方法更改标签名称，如下所示：
@Override
public CharSequence getPageTitle(int position)
switch(position){
case 0:
return "First";
case 1:
return "Second";
case 2:
return "Third";
default:
return "Some";
}
}