我对android非常陌生,学习了一点,我在google搜索技能之上遇到了一个问题。
我有这个:
包含工具栏和viewPager的activity_main布局
fragment_main with button
主要活动是这个,主要是剥离问题:
public class MainActivity extends AppCompatActivity {
private SectionsPagerAdapter mSectionsPagerAdapter;
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);
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
// Set up the ViewPager with the sections adapter.
mViewPager = (ViewPager) findViewById(R.id.container);
mViewPager.setAdapter(mSectionsPagerAdapter);
}
/**
* 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";
private FragmentManager supportFragmentManager;
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)));
Button newFragmentBtn = (Button) rootView.findViewById(R.id.cameraBtn);
newFragmentBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// create new fragment with same layout on right so I can swipe to it
}
});
return rootView;
}
public FragmentManager getSupportFragmentManager() {
return supportFragmentManager;
}
}
/**
* 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() {
return 3;
}
}
}
所以我现在有3个片段(可能是任何数字),但是我希望这不是固定数字,而是当我点击片段内的按钮时增加,这样当我点击在newFragmentBtn上,它会创建4个片段进行滑动,再次点击,5个片段等...
感谢您的帮助。
答案 0 :(得分:0)
将字段fragCount添加到SectionsPagerAdapter(应扩展FragmentStatePagerAdapter),添加setter以更改所需的片段数,并且在更改计数器后不要忘记调用notifyDataSetChanged():
public class SectionsPagerAdapter extends FragmentStatePagerAdapter {
private int fragCount = 3;//initial number
public SectionsPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
return PlaceholderFragment.newInstance(position);
}
public void setCount(int fragCount){
this.fragCount = fragCount;
notifyDataSetChanged();
}
@Override
public int getCount() {
return fragCount;
}
}