从片段动态设置选项卡的标题

Question

我有活动(MainActivity(，它有五个选项卡，每个选项卡包含一个片段。每个片段都包含一个EditText小部件。我想在更改活动片段类中的 EditText 文本时设置活动选项卡的标题。我怎么能在飞行中做到这一点？ 以下是我的资源：

主要活动：

public class MainActivity extends AppCompatActivity {
private SectionsPagerAdapter mSectionsPagerAdapter;
private ViewPager mViewPager;
ImageView imageView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
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) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}

部分寻呼适配器：

public class SectionsPagerAdapter extends FragmentPagerAdapter {
public SectionsPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
switch (position){
case 0:
Tab1 tab1 = new Tab1();
return tab1;
case 1:
Tab2 tab2 = new Tab2();
return tab2;
case 2:
Tab3 tab3 = new Tab3();
return tab3;
case 3:
Tab4 tab4 = new Tab4();
return tab4;
case 4:
Tab5 tab5 = new Tab5();
return tab5;
default:
return null;
}
}
@Override
public int getCount() {
// Show 5 total pages.
return 5;
}
@Override
public CharSequence getPageTitle(int position) {
switch (position) {
case 0:
return "title1";
case 1:
return "title2";
case 2:
return "title3";
case 3:
return "title4";
case 4:
return "title5";
}
return null;
}
}

选项卡 1：

public class Tab1 extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.tab1, container, false);
return rootView;
}
}

这些是由Android Studio生成的，所以我想我应该从这里开始。我想要的，如果我在 Tab1 上有一个EditText，并且我开始输入它，它会将第一个选项卡的标题从"title1"更改为我键入的字符串。

Answer 1

在编辑文本中，您应该在该TextWatcher实例中的EditText上使用addTextChangedListener来动态更改标题。请参阅此代码。

editText.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
//this is your tab index you want to change title of..
tabLayout.getTabAt(1).setText(charSequence);
}
@Override
public void afterTextChanged(Editable editable) {
}
});

希望这有帮助..