Question

我有一个有ActionBarActivity的应用程序，里面我有两个代表每个标签的片段......事情是我在fragment1上有一个列表，其中包含两个值“teste”和“teste2” 但是，当我更改为fragment2（tab2）并再次返回tab1时，它会重复列表中的值，如“teste”，“teste2”，“teste”，“teste2”，我该如何防止这种情况？

TabActionBarActivity：

public class TabActionBarActivity extends Activity {

String contextoId;
String BuId;

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

    ActionBar actionBar = getActionBar();
    actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

    String label1 = getResources().getString(R.string.label1);
    Tab tab = actionBar.newTab();
    tab.setText(label1);

    TabListener<Tab1Fragment> tl = new TabListener<Tab1Fragment>(this, label1, Tab1Fragment.class);

   tab.setTabListener(tl);
    actionBar.addTab(tab);


    String label2 = getResources().getString(R.string.label2);
            tab = actionBar.newTab();
            tab.setText(label2);
            TabListener<Tab2Fragment> tl2 = new TabListener<Tab2Fragment>(this, label2, Tab2Fragment.class);
            tab.setTabListener(tl2);
            actionBar.addTab(tab);


            BuId =  getIntent().getExtras().getString("BUId");
            contextoId = getIntent().getExtras().getString("CId");
            Log.i("BUIdTabFrag", BuId);



}


private class TabListener<T extends Fragment> implements
            ActionBar.TabListener {
        private Fragment mFragment;
        private final Activity mActivity;
        private final String mTag;
        private final Class<T> mClass;


        public TabListener(Activity activity, String tag, Class<T> clz) {
                        mActivity = activity;
                        mTag = tag;
                        mClass = clz;
                    }



        @Override
        public void onTabReselected(Tab tab, FragmentTransaction ft) {
            // TODO Auto-generated method stub

        }




        @Override
        public void onTabSelected(Tab tab, FragmentTransaction ft) {
             // Check if the fragment is already initialized
                        if (mFragment == null) {
                            // If not, instantiate and add it to the activity
                            mFragment = Fragment.instantiate(mActivity, mClass.getName());
                            ft.add(android.R.id.content, mFragment, mTag);
                        } else {
                            // If it exists, simply attach it in order to show it
                            ft.attach(mFragment);
                        }


        }




        @Override
        public void onTabUnselected(Tab tab, FragmentTransaction ft) {
             if (mFragment != null) {
                                 // Detach the fragment, because another one is being attached
                                 ft.detach(mFragment);
                             }


        }




}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.tab_action_bar, menu);
    return true;
}

希望你能帮助我

“EDIT”

如果我这样做：

ft.replace(android.R.id.content, mFragment, mTag).commit();

它给了我一个错误：

log: java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.icenterv2/com.example.admin.TabActionBarActivity}: java.lang.IllegalStateException: commit already called

就在这一行：actionBar.addTab(tab);

和

ft.replace(android.R.id.content, mFragment, mTag);

这种方式再次重复

Answer 1

问题不在您的ListView代码中，而是在您的MainActivity中的ActionBar代码中。您没有正确附加，分离和替换fragments。我有同样的问题。发布MainActivity的代码，我可以帮助您

您需要替换

ft.add(android.R.id.content, mFragment, mTag);

带

ft.replace(android.R.id.content, mFragment, mTag).commit();

因此onTabSelected(Tab tab, FragmentTransaction ft)中的方法应该如下所示

 public void onTabSelected(Tab tab, FragmentTransaction ft) {
         // Check if the fragment is already initialized
                    if (mFragment == null) {
                        // If not, instantiate and add it to the activity
                        mFragment = Fragment.instantiate(mActivity, mClass.getName());
                        ft.replace(android.R.id.content, mFragment, mTag);
                    } else {
                        // If it exists, simply attach it in order to show it
                        ft.attach(mFragment);
                    }


    }

因为现在它正在将fragment“添加”到容器中，为您提供重复项。

错误TabActionBarFragment重复数据[编辑]

1 个答案: