改变方向后碎片消失

Question

2天前我发布了一个问题:TabHost的新布局。所以我决定用片段来创建标签，而不是tabActivity。现在我有3个标签:tab_clients, tab_settings, tab_logut。当我运行我的应用程序tab1显示，如果我旋转我的设备一切工作正常。当我切换到tab2或tab3时，我的惊喜来了，当我旋转设备时，从这些选项卡我得到tab1的视图。这是我的主容器:

公共类applicacionactivity扩展FragmentActivity {

/* Tab identif */
static String TAB_clientes = "Clientes";
static String TAB_settings = "Settings";
static String TAB_logout = "Logout";
TabHost mTabHost;
ClientesActivity fragmentClientes;
SettingsActivity fragmentSettings;
LogoutActivity fragmentLogout;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_aplicacion);
    fragmentClientes = new ClientesActivity();
    fragmentSettings = new SettingsActivity();
    fragmentLogout = new LogoutActivity();
    mTabHost = (TabHost)findViewById(android.R.id.tabhost);
    mTabHost.setOnTabChangedListener(listener);
    mTabHost.setup();
    iniTab();
}   

public void iniTab() {
    Resources res = getResources(); 
    //TabHost.TabSpec: A tab has a tab indicator, content, and a tag that is used to keep track of it. 
    TabHost.TabSpec spec =  mTabHost.newTabSpec(TAB_clientes);
    mTabHost.setCurrentTab(-3);
    //TabHost.TabContentFactory: Makes the content of a tab when it is selected. 
    spec.setContent(new TabHost.TabContentFactory() {
        public View createTabContent(String tag) {
            return findViewById(android.R.id.tabcontent);
        }
    });
    spec.setIndicator(" Clientes ", res.getDrawable(R.drawable.clientes));
    mTabHost.addTab(spec);

    spec =   mTabHost.newTabSpec(TAB_settings);
    spec.setContent(new TabHost.TabContentFactory() {
        public View createTabContent(String tag) {
            return findViewById(android.R.id.tabcontent);
        }
    });
    spec.setIndicator(" Settings ",res.getDrawable(R.drawable.settings));
    mTabHost.addTab(spec);
    spec =   mTabHost.newTabSpec(TAB_logout);
    spec.setContent(new TabHost.TabContentFactory() {
        public View createTabContent(String tag) {
            return findViewById(android.R.id.tabcontent);
        }
    });
    spec.setIndicator(" Logout ",res.getDrawable(R.drawable.logouticon));
    mTabHost.addTab(spec);
}
/*
 * TabChangeListener for change the tab when is selected
 */
TabHost.OnTabChangeListener listener    =   new TabHost.OnTabChangeListener() {
    public void onTabChanged(String tabId) {
        /*Set current tab..*/
        if(tabId.equals(TAB_clientes)){
            pushFragments(tabId, fragmentClientes);
        }else if(tabId.equals(TAB_settings)){
            pushFragments(tabId, fragmentSettings);
        }else if(tabId.equals(TAB_logout)){
            pushFragments(tabId, fragmentLogout);
        }
    }
};
/*
 * insert the fragment into the FrameLayout
 */
public void pushFragments(String tag, Fragment fragment){
    FragmentManager manager = getSupportFragmentManager();
    FragmentTransaction ft = manager.beginTransaction();
    ft.replace(android.R.id.tabcontent, fragment);
    ft.commit();
}

当我点击一个选项卡内的按钮并替换布局时，也会发生同样的情况。当我旋转时，我得到tab1的视图。我不得不说，我已经运行的应用程序，使用tabActivity而不是片段，没有这个问题。这里我有点困惑了

任何帮助都将不胜感激。

编辑:这个问题的解决方案是:

1。-在我的FragmentActivity上创建以下方法:

protected void onSaveInstanceState(Bundle bundle) {
    super.onSaveInstanceState(bundle);
    Fragment fragmentAct = this.getSupportFragmentManager().findFragmentById(android.R.id.tabcontent);
    bundle.putString("fragmentAct", fragmentoActual.getTag());
    Log.e("layout-saving",fragmentAct.getTag());
}

正如你所看到的，我在bundle中保存了我在旋转设备之前看到的片段的标签。

2。-在我的OnCreate方法我的FragmentActivity我添加了以下代码:

if (savedInstanceState != null){
   String value = savedInstanceState.getString("fragmentAct");
   establishLayout(value);
}

3。-我创建了一个名为establishLayout:

的方法

public void establishLayout(String tagFragment){
    mTabHost.setCurrentTabByTag(tagFragment);
    Fragment fragmentoActual = this.getSupportFragmentManager().findFragmentByTag(tagFragment);
    if(fragmentoActual!=null){
        pushFragments(tagFragment, fragmentoActual);
    }
}

4。我创建了方法pushFragments:

public void pushFragments(String tag, Fragment fragment){
    FragmentManager manager = getSupportFragmentManager();
    FragmentTransaction ft = manager.beginTransaction();
    ft.replace(android.R.id.tabcontent, fragment, tag);
    ft.commit();
 }

就是这样!每次我改变设备的方向，我都不会失去活动布局!非常感谢@Yuri给我的帮助:)

Answer 1

当方向改变时，activity被重新创建。您可能需要一个变量来跟踪活动选项卡

• 将变量的值保存在onSaveInstanceState()
• 从savedInstanceState Bundle中恢复onCreate()中的值
• 使用恢复值正确初始化标签

更多关于处理配置更改的信息可以在Android指南中找到:http://developer.android.com/guide/components/activities.html ConfigurationChanges