我正在开发一款只有activity和多个fragments的应用。
第一个fragment包含viewpager，其中fragments额外增加fragment。我可以轻松地从一个viewpager切换到另一个fragment工作正常，但当我从一个viewpager返回到第一个（viewpager）时， fragments未加载所有public class MainActivity extends ActionBarActivity implements View.OnClickListener {
private String[] mOptionMenu;
private DrawerLayout mDrawerLayout;
private DrawerLayout loginlayout;
private RelativeLayout mDrawerRelativeLayout;
private ListView mDrawerList;
private ActionBarDrawerToggle mDrawerToggle;
private CharSequence mTitleSection;
private CharSequence mTitleApp;
private Fragment mFragment = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button btn1= (Button) findViewById(R.id.button1);
Button btn2= (Button) findViewById(R.id.button2);
Button login= (Button) findViewById(R.id.login);
Button about= (Button) findViewById(R.id.about);
about.setOnClickListener(this);
login.setOnClickListener(this);
btn2.setOnClickListener(this);
btn1.setOnClickListener(this);
FontChangeCrawler fontChanger = new FontChangeCrawler(getAssets(), "fonts/font.ttf");
fontChanger.replaceFonts((ViewGroup)this.findViewById(android.R.id.content));
if (findViewById(R.id.content_frame) != null) {
if (savedInstanceState != null) {
return;
}
FirstFragment firstFragment = new FirstFragment();
firstFragment.setArguments(getIntent().getExtras());
getSupportFragmentManager().beginTransaction().addToBackStack(null)
.add(R.id.content_frame, firstFragment).commit();
}
mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
mDrawerRelativeLayout = (RelativeLayout) findViewById(R.id.left_drawer);
mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout,
R.drawable.ic_drawer, R.string.drawer_open,
R.string.drawer_close) {
public void onDrawerClosed(View view) {
getSupportActionBar().setTitle(mTitleSection);
ActivityCompat.invalidateOptionsMenu(MainActivity.this);
}
public void onDrawerOpened(View drawerView) {
getSupportActionBar().setTitle(mTitleSection);
ActivityCompat.invalidateOptionsMenu(MainActivity.this);
}
};
mDrawerLayout.setDrawerListener(mDrawerToggle);
getSupportActionBar().setCustomView(R.layout.actionbar_image);
getSupportActionBar().setDisplayOptions(ActionBar.DISPLAY_SHOW_HOME
| ActionBar.DISPLAY_SHOW_CUSTOM);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setDisplayShowTitleEnabled(false);
getSupportActionBar().setHomeButtonEnabled(true);
getSupportActionBar().setBackgroundDrawable(new ColorDrawable(Color.parseColor("#662e91")));
mDrawerLayout.setDrawerListener(new DrawerLayout.DrawerListener() {
@Override
public void onDrawerSlide(View drawerView, float slideOffset) {
}
@Override
public void onDrawerOpened(View drawerView) {
}
@Override
public void onDrawerClosed(View drawerView) {
}
@Override
public void onDrawerStateChanged(int newState) {
}
});
}
@Override
public void onClick(View v) {
switch(v.getId())
{
case R.id.button1:
FirstFragment firstFragment = new FirstFragment();
getSupportFragmentManager().beginTransaction().replace(R.id.content_frame, new FirstFragment()).commit();
mDrawerLayout.closeDrawer(Gravity.LEFT);
break;
case R.id.login:
callLoginDialog();
break;
case R.id.about:
about abt = new about();
abt.setArguments(getIntent().getExtras());
getSupportFragmentManager().beginTransaction()
.add(R.id.content_frame, abt).commit();
mDrawerLayout.closeDrawer(Gravity.LEFT);
break;
}
}
public class FontChangeCrawler
{
private Typeface typeface;
public FontChangeCrawler(Typeface typeface)
{
this.typeface = typeface;
}
public FontChangeCrawler(AssetManager assets, String assetsFontFileName)
{
typeface = Typeface.createFromAsset(assets, "fonts/font.ttf");
}
public void replaceFonts(ViewGroup viewTree)
{
View child;
for(int i = 0; i < viewTree.getChildCount(); ++i)
{
child = viewTree.getChildAt(i);
if(child instanceof ViewGroup)
{
// recursive call
replaceFonts((ViewGroup)child);
}
else if(child instanceof TextView)
{
// base case
((TextView) child).setTypeface(typeface);
}
}
}
}
public void callLoginDialog()
{
Dialog myDialog = new Dialog(this);
myDialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
myDialog.setContentView(R.layout.loginwindow);
myDialog.setCancelable(false);
TextView reg= (TextView) myDialog.findViewById(R.id.register);
Button login = (Button) myDialog.findViewById(R.id.login);
EditText emailaddr = (EditText) myDialog.findViewById(R.id.editText2);
EditText password = (EditText) myDialog.findViewById(R.id.editText3);
myDialog.show();
reg.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(getApplicationContext(), "Register",
Toast.LENGTH_LONG).show();
}
});
login.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View v)
{
//your login calculation goes here
}
});
myDialog.setOnKeyListener(new DialogInterface.OnKeyListener() {
@Override
public boolean onKey(DialogInterface dialog, int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
dialog.cancel();
return true;
}
return false;
}
});
}
@Override
public void onBackPressed() {
if(mDrawerLayout.isDrawerOpen(Gravity.LEFT)) {
mDrawerLayout.closeDrawer(Gravity.LEFT);
}
else {
super.onBackPressed();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.main, menu);
return super.onCreateOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if (mDrawerToggle.onOptionsItemSelected(item)) {
return true;
}
switch (item.getItemId()) {
case R.id.user:
mDrawerLayout.closeDrawer(Gravity.LEFT);
break;
default:
return super.onOptionsItemSelected(item);
}
return true;
}
@Override
protected void onPostCreate(Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
mDrawerToggle.syncState();
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
mDrawerToggle.onConfigurationChanged(newConfig);
}
}
。以下是代码：
mainactivity.java
public class FirstFragment extends Fragment {
public ViewPager viewPager;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_first,
container, false);
viewPager = (ViewPager) rootView.findViewById(pager);
viewPager.setAdapter(new ViewPagerAdapter(getFragmentManager()));
viewPager.setCurrentItem(0);
PagerTitleStrip pagerTitleStrip= (PagerTitleStrip) rootView.findViewById(R.id.titlestrip);
pagerTitleStrip.setNonPrimaryAlpha(Float.parseFloat("0.3"));
viewPager.setPageTransformer(true, new ViewPager.PageTransformer() {
@Override
public void transformPage(View view, float position) {
final float normalizedposition = Math.abs(Math.abs(position) - 1);
view.setAlpha(normalizedposition);
}
});
Typeface font = Typeface.createFromAsset(getActivity().getAssets(), "fonts/font.ttf");
for (int counter = 0 ; counter<pagerTitleStrip.getChildCount(); counter++) {
if (pagerTitleStrip.getChildAt(counter) instanceof TextView) {
((TextView)pagerTitleStrip.getChildAt(counter)).setTypeface(font);
}
}
return rootView;
}
}
firstfragment.java
public class ViewPagerAdapter extends FragmentPagerAdapter {
final int PAGE_COUNT = 4;
// Tab Titles
private String tabtitles[] = new String[] { "Home", "Men", "Women", "Children" };
Context context;
public ViewPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public int getCount() {
return PAGE_COUNT;
}
@Override
public Fragment getItem(int position) {
switch (position) {
// Open FragmentTab1.java
case 0:
SecondFragment fragmenttab1 = new SecondFragment();
return fragmenttab1;
// Open FragmentTab2.java
case 1:
ThirdFragment fragmenttab2 = new ThirdFragment();
return fragmenttab2;
case 2:
Fourthfragment fragmenttab3 = new Fourthfragment();
return fragmenttab3;
case 3:
FifthFragment fragmenttab4 = new FifthFragment();
return fragmenttab4;
}
return null;
}
@Override
public CharSequence getPageTitle(int position) {
return tabtitles[position];
}
}
viewpageadapter.java
{{1}}
答案 0 :(得分：0)
尝试使用viewPager.setAdapter(new ViewPagerAdapter(getFragmentManager()));
viewPager.setAdapter(new ViewPagerAdapter(getChildFragmentManager()));