<android.support.v4.view.ViewPager
android:id="@+id/view_pager"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
- 自己繼承 PagerAdapter
- 繼承FragmentPagerAdapter
- 繼承FragmentStatePagerAdapter
先來代碼:
public class ViewPagerAdapter1 extends PagerAdapter {
public static final String TAG = ViewPagerAdapter1.class.getSimpleName();
private List<String> mDataList;
private LayoutInflater mLayoutInflater;
public ViewPagerAdapter1(Context context, List<String> dataList) {
mDataList = dataList;
mLayoutInflater = LayoutInflater.from(context);
}
@Override
public int getCount() {
return mDataList.size();
}
@Override
public Object instantiateItem(ViewGroup container, int position) {
LogUtil.d(TAG, "instantiateItem position = " + position);
// 這裏 必須是 null , 不然報錯
View item = mLayoutInflater.inflate(R.layout.item_1, null);
TextView textView = (TextView) item.findViewById(R.id.txt);
textView.setText(mDataList.get(position));
container.addView(item);
return item;
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
container.removeView((View) object);
}
@Override
public boolean isViewFromObject(View view, Object object) {
return view == object;
}
}
public class ViewPagerAdapter2 extends FragmentPagerAdapter {
public static final String TAG = ViewPagerAdapter2.class.getSimpleName();
private List<Fragment> mFragments = new ArrayList<>();
public ViewPagerAdapter2(FragmentManager fm) {
super(fm);
}
public void addFragment(Fragment fragment) {
mFragments.add(fragment);
}
public void removeFragment(Fragment fragment) {
mFragments.remove(fragment);
}
public void setFragments(List<Fragment> fragments) {
mFragments = fragments;
}
public List<Fragment> getFragments() {
return mFragments;
}
public void clear() {
for (Fragment fragment : mFragments) {
if (fragment != null && fragment.isAdded()) {
fragment.onDestroy();
}
}
mFragments.clear();
}
@Override
public Object instantiateItem(ViewGroup container, int position) {
LogUtil.d(TAG, "instantiateItem position = " + position);
return super.instantiateItem(container, position);
}
@Override
public Fragment getItem(int position) {
return mFragments.get(position);
}
@Override
public int getCount() {
return mFragments.size();
}
}
public class ViewPagerAdapter3 extends FragmentStatePagerAdapter {
public static final String TAG = ViewPagerAdapter3.class.getSimpleName();
private List<Fragment> mFragments = new ArrayList<>();
public ViewPagerAdapter3(FragmentManager fm) {
super(fm);
}
public void addFragment(Fragment fragment) {
mFragments.add(fragment);
}
public void removeFragment(Fragment fragment) {
mFragments.remove(fragment);
}
public void setFragments(List<Fragment> fragments) {
mFragments = fragments;
}
public List<Fragment> getFragments() {
return mFragments;
}
public void clear() {
for (Fragment fragment : mFragments) {
if (fragment != null && fragment.isAdded()) {
fragment.onDestroy();
}
}
mFragments.clear();
}
@Override
public Object instantiateItem(ViewGroup container, int position) {
LogUtil.d(TAG, "instantiateItem position = " + position);
return super.instantiateItem(container, position);
}
@Override
public Fragment getItem(int position) {
return mFragments.get(position);
}
@Override
public int getCount() {
return mFragments.size();
}
}
public class MyFragment extends Fragment {
public final static String TAG = "MyFragment";
public final static String SaveInstanceStateEXTRA = "SaveInstanceStateEXTRA";
String mData;
public static MyFragment getInstances(String data) {
MyFragment myFragment = new MyFragment();
myFragment.mData = data;
return myFragment;
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
LogUtil.d(TAG, "onCreateView mData = " + mData);
String str = "";
if (savedInstanceState != null) {
str = savedInstanceState.getString("SaveInstanceStateEXTRA");
}
// 這裏必須是null
View item = inflater.inflate(R.layout.item_1, null);
TextView textView = (TextView) item.findViewById(R.id.txt);
textView.setText(mData);
if (!TextUtils.isEmpty(str)) {
textView.setText(str);
}
return item;
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putString(SaveInstanceStateEXTRA, mData + "_save");
LogUtil.d(TAG, "onSaveInstanceState mData = " + mData);
}
@Override
public void onDestroy() {
super.onDestroy();
LogUtil.d(TAG, "onDestroy mData = " + mData);
}
}