Use of ViewPager and Fragment in Android
- 2021-07-22 11:28:27
- OfStack
Small case
In XML
<android.support.v4.view.ViewPager
android:id="@+id/viewPager"
android:layout_width="match_parent"
android:layout_height="match_parent">
</android.support.v4.view.ViewPager>
Create Fragment
fragments = new ArrayList<>();
ConversationFragment fragment1 = new ConversationFragment();
GroupFragment fragment2 = new GroupFragment();
SearchFragment fragment3 = new SearchFragment();
fragments.add(fragment1);
fragments.add(fragment2);
fragments.add(fragment3);
adapter = new MainPagerAdapter(getSupportFragmentManager(), fragments);
viewPager.setAdapter(adapter);
adapter
public class MainPagerAdapter extends FragmentPagerAdapter{
List<Fragment> fragmentList;
public MainPagerAdapter(FragmentManager fm, List<Fragment> fragmentList) {
super(fm);
this.fragmentList = fragmentList;
}
@Override
public Fragment getItem(int position) {
return fragmentList.get(position);
}
@Override
public int getCount() {
return fragmentList.size();
}
}
OnPageChangeListener
viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
int distance = positionOffsetPixels / 3;
//1 Dan fragment Slide, here's position Actually before 1 A
ViewPropertyAnimator.animate(v_indicate_line).translationX(distance + position * v_indicate_line.getWidth()).setDuration(0);
}
@Override
public void onPageSelected(int position) {
textLightAndSize();
}
@Override
public void onPageScrollStateChanged(int state) {
}
});
Cooperate with other click events
// Here is the note setCurrentItem Usage of
switch (view.getId()) {
case R.id.ly_conversation:
viewPager.setCurrentItem(0);
break;
case R.id.ly_group:
viewPager.setCurrentItem(1);
break;
case R.id.ly_search:
viewPager.setCurrentItem(2);
break;
}
Official case
R.layout.fragment_pager
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:padding="4dip"
android:gravity="center_horizontal"
android:layout_width="match_parent" android:layout_height="match_parent">
<android.support.v4.view.ViewPager
android:id="@+id/pager"
android:layout_width="match_parent"
android:layout_height="0px"
android:layout_weight="1">
</android.support.v4.view.ViewPager>
<LinearLayout android:orientation="horizontal"
android:gravity="center" android:measureWithLargestChild="true"
android:layout_width="match_parent" android:layout_height="wrap_content"
android:layout_weight="0">
<Button android:id="@+id/goto_first"
android:layout_width="wrap_content" android:layout_height="wrap_content"
android:text="@string/first">
</Button>
<Button android:id="@+id/goto_last"
android:layout_width="wrap_content" android:layout_height="wrap_content"
android:text="@string/last">
</Button>
</LinearLayout>
</LinearLayout>
R.layout.fragment_pager_list
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@android:drawable/gallery_thumb">
<TextView android:id="@+id/text"
android:layout_width="match_parent" android:layout_height="wrap_content"
android:gravity="center_vertical|center_horizontal"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="@string/hello_world"/>
<!-- The frame layout is here since we will be showing either
the empty view or the list view. -->
<FrameLayout
android:layout_width="match_parent"
android:layout_height="0dip"
android:layout_weight="1" >
<!-- Here is the list. Since we are using a ListActivity, we
have to call it "@android:id/list" so ListActivity will
find it -->
<ListView android:id="@android:id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:drawSelectorOnTop="false"/>
<!-- Here is the view to show if the list is emtpy -->
<TextView android:id="@android:id/empty"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="No items."/>
</FrameLayout>
</LinearLayout>
public class FragmentPagerSupport extends FragmentActivity {
static final int NUM_ITEMS = 10;
MyAdapter mAdapter;
ViewPager mPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_pager);
mAdapter = new MyAdapter(getSupportFragmentManager());
mPager = (ViewPager)findViewById(R.id.pager);
mPager.setAdapter(mAdapter);
// Watch for button clicks.
Button button = (Button)findViewById(R.id.goto_first);
button.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
mPager.setCurrentItem(0);
}
});
button = (Button)findViewById(R.id.goto_last);
button.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
mPager.setCurrentItem(NUM_ITEMS-1);
}
});
}
public static class MyAdapter extends FragmentPagerAdapter {
public MyAdapter(FragmentManager fm) {
super(fm);
}
@Override
public int getCount() {
return NUM_ITEMS;
}
@Override
public Fragment getItem(int position) {
return ArrayListFragment.newInstance(position);
}
}
public static class ArrayListFragment extends ListFragment {
int mNum;
/**
* Create a new instance of CountingFragment, providing "num"
* as an argument.
*/
static ArrayListFragment newInstance(int num) {
ArrayListFragment f = new ArrayListFragment();
// Supply num input as an argument.
Bundle args = new Bundle();
args.putInt("num", num);
f.setArguments(args);
return f;
}
/**
* When creating, retrieve this instance's number from its arguments.
*/
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mNum = getArguments() != null ? getArguments().getInt("num") : 1;
}
/**
* The Fragment's UI is just a simple text view showing its
* instance number.
*/
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_pager_list, container, false);
View tv = v.findViewById(R.id.text);
((TextView)tv).setText("Fragment #" + mNum);
return v;
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
setListAdapter(new ArrayAdapter<String>(getActivity(),
android.R.layout.simple_list_item_1, Cheeses.sCheeseStrings));
}
@Override
public void onListItemClick(ListView l, View v, int position, long id) {
Log.i("FragmentList", "Item clicked: " + id);
}
}
}
Attention
fragment is not available for Activity prior to 3.0. In order to use fragment (in supportV4), FragmentActivity came into being. FragmentActivity inherits from Activity.
The above is the whole content of this article, hoping to help everyone learn Android software programming.