片段不会显示在活动

Question

我想创建一个屏幕，将有一个3按钮的片段，并在它下面的文本框架，但我没有看到任何东西，当我运行应用程序。 我是Android新手，所以我假设我缺少一些基本的东西。 我错过了什么？

编辑：谢谢你的所有答案。问题最终是因为按钮的大小不可见。 活动确实加载了片段，而无需调用片段管理器。

哦，学习一门新的框架:)

感谢您的乐趣！

activity_main.xml中

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
xmlns:tools="http://schemas.android.com/tools" 
android:layout_width="match_parent" 
android:layout_height="match_parent" 
android:orientation="vertical"> 

<fragment 
    android:id="@+id/buttons" 
    android:layout_width="match_parent" 
    android:layout_height="400dp" 
    class="com.thenoisemargins.eyaldagiavdor.thisdaybefore.ButtonsFragment" /> 

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:layout_width="match_parent" 
    android:layout_height="100dp"> 

    <TextView 
     android:layout_width="48dp" 
     android:layout_height="45dp" 
     android:id="@+id/historicalQuoteTextView" 
     android:layout_gravity="center_vertical" 
     android:textAlignment="center" 
     android:textColor="#FFFFFFFF" 
     android:text="Quote" 
     android:layout_centerVertical="true" 
     android:layout_alignParentLeft="true" 
     android:layout_alignParentStart="true" /> 

</FrameLayout> 

buttons_fragment.xml

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:app="http://schemas.android.com/apk/res-auto" 
    android:orientation="vertical" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent"> 
<at.markushi.ui.CircleButton 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:clickable="true" 
    android:text="@string/this_day_before" 
    android:id="@+id/thisDayBeforeButton" 
    app:cb_color="#99CC00" 
    app:cb_pressedRingWidth="8dip" /> 

<at.markushi.ui.CircleButton 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:clickable="true" 
    android:text="@string/choose_date" 
    android:id="@+id/ChooseDateButton" 
    app:cb_color="#99CC00" 
    app:cb_pressedRingWidth="8dip" /> 

<at.markushi.ui.CircleButton 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:clickable="true" 
    android:text="@string/random_date" 
    android:id="@+id/RandomDateButton" 
    app:cb_color="#99CC00" 
    app:cb_pressedRingWidth="8dip" /> 
</LinearLayout> 

MainActivity.java

public class MainActivity extends ActionBarActivity { 

    private ButtonsFragment mFragment; 

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

     /* 
     FragmentManager fragmentManager = getFragmentManager(); 
     FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction(); 
     mFragment = new ButtonsFragment(); 
     fragmentTransaction.add(R.id.buttons, mFragment); 
     fragmentTransaction.commit(); 
       */ 

     mFragment = (ButtonsFragment) getFragmentManager() 
       .findFragmentById(R.id.buttons); 


    } 


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

    @Override 
    public boolean onOptionsItemSelected(MenuItem item) { 
     // Handle action bar item clicks here. The action bar will 
     // automatically handle clicks on the Home/Up button, so long 
     // as you specify a parent activity in AndroidManifest.xml. 
     int id = item.getItemId(); 

     //noinspection SimplifiableIfStatement 
     if (id == R.id.action_settings) { 
      return true; 
     } 

     return super.onOptionsItemSelected(item); 
    } 
} 

ButtonsFragment.java

public class ButtonsFragment extends Fragment { 

private at.markushi.ui.CircleButton mThisDayBeforeButton; 
private at.markushi.ui.CircleButton mChooseDateButton; 
private at.markushi.ui.CircleButton mRandomDateButton; 


@Override 
public View onCreateView(LayoutInflater inflater, ViewGroup container, 
         Bundle savedInstanceState) { 

    View rootView = inflater.inflate(R.layout.buttons_fragment, container, false); 



    return rootView; 
} 

@Override 
public void onActivityCreated(Bundle savedInstanceState) { 
    super.onActivityCreated(savedInstanceState); 

    mThisDayBeforeButton = (at.markushi.ui.CircleButton) getActivity().findViewById(R.id.thisDayBeforeButton); 
    mChooseDateButton = (at.markushi.ui.CircleButton) getActivity().findViewById(R.id.ChooseDateButton); 
    mRandomDateButton = (at.markushi.ui.CircleButton) getActivity().findViewById(R.id.RandomDateButton); 

} 

}上给出部分

Answer 1

删除评论。您必须使用fragmentTransaction将片段添加到fragmentManager中才能查看片段。

mFragment = (ButtonsFragment) getFragmentManager() 
       .findFragmentById(R.id.buttons); 

      FragmentManager fragmentManager = getFragmentManager(); 
      FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction(); 
      mFragment = new ButtonsFragment(); 
      fragmentTransaction.add(R.id.buttons, mFragment); 
      fragmentTransaction.commit(); 

Answer 2

试试这个，如果工作

FragmentManager fragmentManager = getFragmentManager(); 
      FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction(); 
      mFragment = new ButtonsFragment(); 
      fragmentTransaction.add(R.id.buttons, mFragment); 
      fragmentTransaction.commit(); 

上面的代码替换这一点，并尝试可能工作。

FragmentManager fragmentManager = getFragmentManager(); 
      fragmentManager.beginTransaction() 
        .replace(R.id.buttons, fragment).commit(); 

Answer 3

如果你想直接在XML则显示片段，

<fragment 
android:id="@+id/buttons" 
android:layout_width="match_parent" 
android:layout_height="400dp" 
class="com.thenoisemargins.eyaldagiavdor.thisdaybefore.ButtonsFragment" /> 

或者，如果你想以编程方式显示，您需要使用

getSupportFragmentManager（）

因为您使用的是ActionbarActivity，如： add f ramelayou与id'框架'（示例）在布局，然后将此代码添加到您的活动

FrameLayout f = (FrameLayout) findViewById(R.id.fram); 
    getSupportFragmentManager().beginTransaction().replace(R.id.fram, new ButtonsFragment()).commit(); 

希望这有助于！