package org.aisen.wen.ui.fragment;
import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.text.TextUtils;
import android.view.View;
import org.aisen.wen.R;
import org.aisen.wen.R2;
import org.aisen.wen.base.GlobalContext;
import org.aisen.wen.support.bean.TabItem;
import org.aisen.wen.support.utils.Logger;
import org.aisen.wen.support.utils.SharedPreferencesUtils;
import org.aisen.wen.ui.activity.BaseActivity;
import org.aisen.wen.ui.adapter.FragmentPagerAdapter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import butterknife.BindView;
/**
* 维护一个ViewPager的Fragemnt
*
* Created by wangdan on 15/12/22.
*/
public abstract class ATabsFragment<T extends TabItem> extends ABaseFragment
implements ViewPager.OnPageChangeListener {
static final String TAG = "AFragment-Tabs";
public static final String SET_INDEX = "org.aisen.android.ui.SET_INDEX";// 默认选择第几个
@BindView(R2.id.viewPager)
ViewPager mViewPager;
FragmentPagerAdapter mInnerAdapter;
ArrayList<T> mItems;
Map<String, Fragment> fragments;
int mCurrentPosition = 0;
private boolean isRetainFragments = false;// 如果系统先调用onSaveInstanceState方法，说明添加的Fragments是需要保留的
@Override
public int setLayoutId() {
return R.layout.comm_ui_tabs;
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
mCurrentPosition = mViewPager.getCurrentItem();
outState.putSerializable("items", mItems);
outState.putInt("current", mCurrentPosition);
isRetainFragments = true;
}
@Override
public void bindView(View contentView, final Bundle savedInstanceState) {
super.bindView(contentView, savedInstanceState);
mItems = savedInstanceState == null ? generateTabs()
: (ArrayList<T>) savedInstanceState.getSerializable("items");
mCurrentPosition = savedInstanceState == null ? 0
: savedInstanceState.getInt("current");
if (delayTabInit() == 0) {
setTabInit(savedInstanceState);
}
else {
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
setTabInit(savedInstanceState);
}
}, delayTabInit());
}
}
protected void setTabInit(final Bundle savedInstanceSate) {
if (getActivity() == null) {
return;
}
else if (getActivity() instanceof BaseActivity) {
if (((BaseActivity) getActivity()).isDestory()) {
return;
}
}
if (savedInstanceSate == null) {
if (getArguments() != null && getArguments().containsKey(SET_INDEX)) {
mCurrentPosition = Integer.parseInt(getArguments().getSerializable(SET_INDEX).toString());
}
else {
if (configLastPositionKey() != null) {
// 记录了最后阅读的标签
String type = SharedPreferencesUtils.getShareData(GlobalContext.getInstance(), "PagerLastPosition" + configLastPositionKey(), "");
if (!TextUtils.isEmpty(type)) {
for (int i = 0; i < mItems.size(); i++) {
TabItem item = mItems.get(i);
if (type.equals(item.getType())) {
mCurrentPosition = i;
break;
}
}
}
}
}
}
Logger.d(TAG, "CurrentPosition " + mCurrentPosition);
fragments = new HashMap<>();
// 初始化的时候，移除一下Fragment
if (savedInstanceSate == null) {
for (int i = 0; i < mItems.size(); i++) {
Fragment fragment = getActivity().getFragmentManager().findFragmentByTag(makeFragmentName(i));
if (fragment != null) {
getActivity().getFragmentManager().beginTransaction()
.remove(fragment).commit();
}
}
}
setupViewPager(savedInstanceSate);
}
protected void setupViewPager(final Bundle savedInstanceSate) {
mInnerAdapter = new InnerAdapter(getFragmentManager());
mViewPager.setOffscreenPageLimit(0);
mViewPager.setAdapter(mInnerAdapter);
if (mCurrentPosition >= mInnerAdapter.getCount())
mCurrentPosition = 0;
mViewPager.setCurrentItem(mCurrentPosition);
mViewPager.addOnPageChangeListener(this);
}
protected void destoryFragments() {
if (getActivity() != null) {
if (getActivity() instanceof BaseActivity) {
BaseActivity mainActivity = (BaseActivity) getActivity();
if (mainActivity.isDestory())
return;
}
try {
FragmentTransaction trs = getFragmentManager().beginTransaction();
Set<String> keySet = fragments.keySet();
for (String key : keySet) {
if (fragments.get(key) != null) {
trs.remove(fragments.get(key));
Logger.d(TAG, "remove fragment , key = " + key);
}
}
trs.commit();
} catch (Throwable e) {
Logger.printExc(getClass(), e);
}
}
}
@Override
public void onPageScrolled(int i, float v, int i2) {
}
@Override
public void onPageSelected(int position) {
mCurrentPosition = position;
if (configLastPositionKey() != null) {
SharedPreferencesUtils.putShareData(GlobalContext.getInstance(), "PagerLastPosition" + configLastPositionKey(), mItems.get(position).getType());
}
// 查看是否需要拉取数据
Fragment fragment = getCurrentFragment();
if (fragment instanceof ITabInitData) {
((ITabInitData) fragment).onTabRequestData();
}
}
@Override
public void onPageScrollStateChanged(int position) {
}
public String makeFragmentName(int position) {
return mItems.get(position).getTitle();
}
public List<T> getTabItems() {
return mItems;
}
public PagerAdapter getPageAdapter() {
return mInnerAdapter;
}
// 是否保留最后阅读的标签
protected String configLastPositionKey() {
return null;
}
/**
* 标签页，标签不能重复
*
* @return
*/
abstract protected ArrayList<T> generateTabs();
abstract protected Fragment newFragment(T bean);
// 延迟一点初始化tabs，用于在首页切换菜单的时候，太多的tab页导致有点点卡顿
protected int delayTabInit() {
return 0;
}
@Override
public void onDestroy() {
try {
if (!isRetainFragments) {
destoryFragments();
}
} catch (Exception e) {
e.printStackTrace();
}
super.onDestroy();
}
public Fragment getCurrentFragment() {
if (mViewPager == null || mInnerAdapter == null || mInnerAdapter.getCount() < mCurrentPosition)
return null;
return fragments.get(makeFragmentName(mCurrentPosition));
}
public Fragment getFragment(String tabTitle) {
if (fragments == null || TextUtils.isEmpty(tabTitle))
return null;
for (int i = 0; i < mItems.size(); i++) {
if (tabTitle.equals(mItems.get(i).getTitle())) {
return fragments.get(makeFragmentName(i));
}
}
return null;
}
public Fragment getFragment(int index) {
if (mItems.size() > index) {
return fragments.get(makeFragmentName(index));
}
return null;
}
public Map<String, Fragment> getFragments() {
return fragments;
}
public ViewPager getViewPager() {
return mViewPager;
}
class InnerAdapter extends FragmentPagerAdapter {
public InnerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
Fragment fragment = fragments.get(makeFragmentName(position));
if (fragment == null) {
fragment = newFragment(mItems.get(position));
fragments.put(makeFragmentName(position), fragment);
}
return fragment;
}
@Override
protected void freshUI(int position, Fragment fragment) {
super.freshUI(position, fragment);
if (!fragments.containsValue(fragment)) {
fragments.put(makeFragmentName(position), fragment);
}
}
@Override
public int getCount() {
return mItems.size();
}
@Override
public CharSequence getPageTitle(int position) {
return mItems.get(position).getTitle();
}
@Override
protected String makeFragmentName(int position) {
return ATabsFragment.this.makeFragmentName(position);
}
}
// 这个接口用于多页面时，只有当前的页面才加载数据，其他不显示的页面暂缓加载
// 当每次onPagerSelected的时候，再调用这个接口初始化数据
public interface ITabInitData {
void onTabRequestData();
}
}