6

這將是最後一個問題,我有標籤,我保證:)(也許) ,並嘗試和錯誤我已經FragmentPagerAdapter稱爲PagerAdapter它創建一些標籤,也使我動態地創建新標籤的能力。 的問題是,新的標籤總是會得到插入到現有的標籤右邊:從以前的問題,所以添加標籤的左邊與FragmentPagerAdapter

(圖片說明:http://s7.directupload.net/file/d/3198/73dyzvzv_png.htm

我試過如下:

  1. 添加的「靜態條目當創建「Temp Tab」時,我可以將該條目覆蓋到我想要的任何片段上,給我一些奇怪的IllegalSTateException ...

  2. 的事情,我想會的工作最好的居然真的想不好工作:而不是與添加片段:

    private final List<Fragment> mFragments = new ArrayList<Fragment>(); 
    
    public void addFragment(Fragment fragment) { 
        mFragments.add(fragment); 
        notifyDataSetChanged(); 
    } 
    

使用

mFragments.add(0, fragment); 

但它給與消息的IllegalStateException :

Can't change tag of fragment ChatFragment 

當我嘗試添加臨時片段。 現在,兩個問題:

  1. 有周圍的片段標籤的方式,我可以拿走所有的片段標記了片刻,重建他們的所有的東西?或

  2. 有沒有更好更優雅的方式來做到這一點?或者我應該重新設計我的用戶界面,以便該選項卡可以用於正確的? :P

編輯:這裏是一些代碼:(我再也不想只是後死亡牆的人,因爲它可能他們嚇跑:O)

FragmentPagerAdapter:

public class PagerAdapter extends FragmentPagerAdapter { 

    private Context mContext; 

    public PagerAdapter(FragmentManager fm, Context context) { 
    super(fm); 
    mContext = context; 
    } 

    private final List<Fragment> mFragments = new ArrayList<Fragment>(); 
    public void addFragment(Fragment fragment) { 
    mFragments.add(fragment); 
    notifyDataSetChanged(); 
    } 

    @Override 
    public Fragment getItem(int position) { 
    return mFragments.get(position); 
    } 

    @Override 
    public int getCount() { 
    return mFragments.size(); 
    } 

    @Override 
    public String getPageTitle(int position) { 

    switch (position) { 
    case 0: 
     return mContext.getString(R.string.tab_title_chats); 
    case 1: 
     return mContext.getString(R.string.tab_title_contacts); 
    case 2: 
     return mContext.getString(R.string.tab_title_create); 
    } 
    return "WOOPS"; 

    } 

} 

MainActivty :

public class LaunchActivity extends FragmentActivity implements ActionBar.TabListener { 

    private PagerAdapter mAdapter; 
    private FragmentManager man; 
    private ViewPager mViewPager; 
    private ActionBar actionBar; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.layout_container); 

    // Set up the action bar. 
    actionBar = getActionBar(); 
    actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS); 

    // Layout stuff 
    mViewPager = (ViewPager) findViewById(R.id.masterViewPager); 

    // Creating the mAdapter and initializing the mViewPager 
    man = getSupportFragmentManager(); 
    mAdapter = new PagerAdapter(man, getApplicationContext()); 
    mViewPager.setAdapter(mAdapter); 

    for (int i = 0; i < 2; i++) { 
     makeFragments(i); 
     System.out.println("Baking tasty fragment instances...nom nom nom"); 
    } 

    // Called when tab changes 
    mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() { 
     @Override 
     public void onPageSelected(int position) { 
     actionBar.setSelectedNavigationItem(position); 
     } 
    }); 

    for (int i = 0; i < mAdapter.getCount(); i++) { 
     System.out.println("Working..."); 

     actionBar.addTab(actionBar.newTab().setText(mAdapter.getPageTitle(i)).setTabListener(this)); 
    } 

    } 

    // Add fragment instances to ArrayList depending on their future position on the ActionBar 
    private void makeFragments(int i) { 

    if (i == 0) { 
     mAdapter.addFragment(ChatFragment.getInstance()); 

    } 
    else if (i == 1) { 
     mAdapter.addFragment(ContactFragment.getInstance()); 
    } 
    } 

    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
    getMenuInflater().inflate(R.menu.layout_container, menu); 
    return true; 

    } 

    @Override 
    public void onTabSelected(Tab tab, FragmentTransaction ft) { 
    mViewPager.setCurrentItem(tab.getPosition()); 

    } 

    public void addTab(int i) { 
    mAdapter.addFragment(ComposeFragment.getInstance()); 
    System.out.println("Created new Fragment, now adding it as a tab"); 
    actionBar.addTab(actionBar.newTab().setText(mAdapter.getPageTitle(i)).setTabListener(this)); 
    System.out.println("Added it as a tab. Hurray"); 

    } 

    /** IGNORE BELOW **/ 

    @Override 
    public void onTabUnselected(Tab tab, FragmentTransaction ft) { 
    } 

    @Override 
    public void onTabReselected(Tab tab, FragmentTransaction ft) { 
    } 



} 

堆棧跟蹤:

03-18 18:32:29.274: E/AndroidRuntime(26435): FATAL EXCEPTION: main 
    03-18 18:32:29.274: E/AndroidRuntime(26435): java.lang.IllegalStateException: Can't change tag of fragment ChatFragment{41492428 #1 id=0x7f070004 android:switcher:2131165188:1}: was android:switcher:2131165188:1 now android:switcher:2131165188:2 
    03-18 18:32:29.274: E/AndroidRuntime(26435): at android.support.v4.app.BackStackRecord.doAddOp(BackStackRecord.java:398) 
    03-18 18:32:29.274: E/AndroidRuntime(26435): at android.support.v4.app.BackStackRecord.add(BackStackRecord.java:389) 
    03-18 18:32:29.274: E/AndroidRuntime(26435): at android.support.v4.app.FragmentPagerAdapter.instantiateItem(FragmentPagerAdapter.java:99) 
    03-18 18:32:29.274: E/AndroidRuntime(26435): at android.support.v4.view.ViewPager.addNewItem(ViewPager.java:801) 
    03-18 18:32:29.274: E/AndroidRuntime(26435): at android.support.v4.view.ViewPager.populate(ViewPager.java:992) 
    03-18 18:32:29.274: E/AndroidRuntime(26435): at android.support.v4.view.ViewPager.setCurrentItemInternal(ViewPager.java:523) 
    03-18 18:32:29.274: E/AndroidRuntime(26435): at android.support.v4.view.ViewPager.setCurrentItemInternal(ViewPager.java:495) 
    03-18 18:32:29.274: E/AndroidRuntime(26435): at android.support.v4.view.ViewPager.dataSetChanged(ViewPager.java:875) 
    03-18 18:32:29.274: E/AndroidRuntime(26435): at android.support.v4.view.ViewPager$PagerObserver.onChanged(ViewPager.java:2690) 
    03-18 18:32:29.274: E/AndroidRuntime(26435): at android.database.DataSetObservable.notifyChanged(DataSetObservable.java:37) 
    03-18 18:32:29.274: E/AndroidRuntime(26435): at android.support.v4.view.PagerAdapter.notifyDataSetChanged(PagerAdapter.java:276) 
    03-18 18:32:29.274: E/AndroidRuntime(26435): at com.package.subpackage.components.PagerAdapter.addFragment(PagerAdapter.java:25) 
    03-18 18:32:29.274: E/AndroidRuntime(26435): at com.package.subpackage.someapp.core.LaunchActivity.addTab(LaunchActivity.java:116) 
    03-18 18:32:29.274: E/AndroidRuntime(26435): at com. 

com.package.subpackage.fragments.full.ChatFragment$1.onClick(ChatFragment.java:51) 
03-18 18:32:29.274: E/AndroidRuntime(26435): at android.view.View.performClick(View.java:4204) 
03-18 18:32:29.274: E/AndroidRuntime(26435): at android.view.View$PerformClick.run(View.java:17355) 
03-18 18:32:29.274: E/AndroidRuntime(26435): at android.os.Handler.handleCallback(Handler.java:725) 
03-18 18:32:29.274: E/AndroidRuntime(26435): at android.os.Handler.dispatchMessage(Handler.java:92) 
03-18 18:32:29.274: E/AndroidRuntime(26435): at android.os.Looper.loop(Looper.java:137) 
03-18 18:32:29.274: E/AndroidRuntime(26435): at android.app.ActivityThread.main(ActivityThread.java:5041) 
03-18 18:32:29.274: E/AndroidRuntime(26435): at java.lang.reflect.Method.invokeNative(Native Method) 
03-18 18:32:29.274: E/AndroidRuntime(26435): at java.lang.reflect.Method.invoke(Method.java:511) 
03-18 18:32:29.274: E/AndroidRuntime(26435): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793) 
03-18 18:32:29.274: E/AndroidRuntime(26435): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560) 
03-18 18:32:29.274: E/AndroidRuntime(26435): at dalvik.system.NativeStart.main(Native Method) 
+0

發佈您的整個代碼如果可能的話後整個堆棧跟蹤 – Triode 2013-03-18 17:21:25

+0

完成。添加了MainActivity(其中包含所有選項卡管理),並且addFragment函數中的PagerAdapter – AreusAstarte 2013-03-18 17:33:42

+0

將此行代碼更改爲mFragments.add(fragment);到mFragments.add(0,fragment);這個。 – Triode 2013-03-18 17:37:58

回答

0

我可以通過覆蓋OnPageChangeListener的onPageSelected方法來實現此目的。考慮你有三個頁面,按照這個順序A < - > B < - > C。目標是如果我們從A向右滾動,並且如果從C向左滾動,則達到C.

爲此,定義爲具有5頁(3 + 2),以及組織頁面如下:

Ç< - >甲< - >乙< - 「ç< - >甲

現在在onPageSelected方法中,檢查位置是否爲0,將其更改爲3(getCount() - 2),如果位置爲4(getCount() - 1),則將其更改爲1。幫助你。

感謝