我目前遇到的问题是将ViewPager中的某个片段替换为另一个片段。要替换的片段ID是我的“Departments”，它具有Imagebutton id，用于开始替换。我试图从其他类似的问题中应用一些建议（其中大部分是旧的，在新的api发布之前允许嵌套片段）并且没有成功。使用嵌套片段会更容易吗？我是Android应用程序开发的新手，所以任何帮助都会很棒。提前谢谢。
这是我的FragmentAcitivty
public class ViewPagerStyle extends FragmentActivity {
private ViewPager mViewPager;
private ViewPagerAdapter adapter;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
setUpView();
setTab();
}
private void setUpView(){
mViewPager = (ViewPager) findViewById(R.id.viewPager);
adapter = new ViewPagerAdapter(getApplicationContext(),getSupportFragmentManager());
mViewPager.setAdapter(adapter);
mViewPager.setCurrentItem(0);
}
private void setTab(){
mViewPager.setOnPageChangeListener(new OnPageChangeListener(){
@Override
public void onPageScrollStateChanged(int position) {}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {}
@Override
public void onPageSelected(int position) {
// TODO Auto-generated method stub
switch(position){
case 0:
findViewById(R.id.first_tab).setVisibility(View.VISIBLE);
findViewById(R.id.second_tab).setVisibility(View.INVISIBLE);
findViewById(R.id.third_tab).setVisibility(View.INVISIBLE);
break;
case 1:
findViewById(R.id.first_tab).setVisibility(View.INVISIBLE);
findViewById(R.id.second_tab).setVisibility(View.VISIBLE);
findViewById(R.id.third_tab).setVisibility(View.INVISIBLE);
break;
case 2:
findViewById(R.id.first_tab).setVisibility(View.INVISIBLE);
findViewById(R.id.second_tab).setVisibility(View.INVISIBLE);
findViewById(R.id.third_tab).setVisibility(View.VISIBLE);
break;
}
}
});
}
}
FragmentPagerAdapter
public class ViewPagerAdapter extends FragmentPagerAdapter {
private Context _context;
public ViewPagerAdapter(Context context, FragmentManager fm) {
super(fm);
_context = context;
}
@Override
public Fragment getItem(int position) {
Fragment f = new Fragment();
switch(position){
case 0:
f=PubView.newInstance(_context);
break;
case 1:
f=MyView.newInstance(_context);
break;
case 2:
f=Departments.newInstance(_context);
break;
}
return f;
}
@Override
public int getCount() {
return 3;
}
}
Departments Fragment with button
public class Departments extends Fragment {
public static Fragment newInstance(Context context) {
Departments f = new Departments();
return f;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {
View root = (View) inflater.inflate(R.layout.activity_departments, null);
ImageButton engineeringButton = (ImageButton)root.findViewById(R.id.engineeringButton);
engineeringButton.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v){
Fragment newFragment = Engineering.newInstance(null);
FragmentTransaction transaction = getChildFragmentManager().beginTransaction();
transaction.addToBackStack(null);
transaction.replace(R.id.viewPager, newFragment).commit();
}
});
return root;
}
}
此外，这是我的main.xml文件，它承载了viewpager
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@color/purple"
android:orientation="vertical" >
<TableLayout
style="@style/layout_f_w"
android:stretchColumns="*" >
<TableRow
android:id="@+id/tableRow1"
style="@style/layout_wrap"
android:background="@color/white" >
<!-- First Tab -->
<LinearLayout
android:id="@+id/first_text"
style="@style/layout_f_w"
android:orientation="vertical" >
<TextView
android:id="@+id/textView1"
style="@style/text_title"
android:text="pubView"
android:textColor="@color/purple" />
</LinearLayout>
<!-- Second Tab -->
<LinearLayout
android:id="@+id/second_text"
style="@style/layout_f_w"
android:orientation="vertical" >
<TextView
android:id="@+id/textView1"
style="@style/text_title"
android:gravity="center"
android:text="myView"
android:textColor="@color/purple" />
</LinearLayout>
<!-- Third Tab -->
<LinearLayout
android:id="@+id/third_text"
style="@style/layout_f_w"
android:orientation="vertical" >
<TextView
android:id="@+id/textView1"
style="@style/text_title"
android:text="Dept."
android:textColor="@color/purple" />
</LinearLayout>
</TableRow>
</TableLayout>
<!-- Include Tab Indicator -->
<include
android:layout_width="fill_parent"
android:layout_height="wrap_content"
layout="@layout/indicator" />
<android.support.v4.view.ViewPager
android:id="@+id/viewPager"
android:layout_width="fill_parent"
android:layout_height="450dp" />
<ImageButton
android:id="@+id/settingsButton"
android:layout_width="wrap_content"
android:layout_height="30dp"
android:layout_marginLeft="50dp"
android:background="@drawable/settings_button"
android:src="@drawable/settings_button" />
</LinearLayout>
我感到困惑的一件事是，我不知道将哪个id放入transaction.replace（r.id.viewPager，newfragment）的第一个参数中......我读过它需要容器的id但是当我使用它时，我从logcat收到运行时错误：
04-13 21:41:48.680: E/AndroidRuntime(960): java.lang.IllegalArgumentException: No view found for id 0x7f0a0029 (com.pvcalendar:id/viewPager) for fragment Engineering{4089a730 #0 id=0x7f0a0029}
答案 0 :(得分：1)
我认为重点是将片段用作容器。
在ViewPagerAdapter中：
@Override
public Fragment getItem(int position) {
/*
* IMPORTANT: This is the point. We create a RootFragment acting as
* a container for other fragments
*/
if (position == 0)
return new RootFragment();
else
return new StaticFragment();
}
RootFragment布局应如下所示：
<FrameLayout 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:id="@+id/root_frame" >
</FrameLayout>
直接用你的第一个“真实”片段填充它：
public class RootFragment extends Fragment {
private static final String TAG = "RootFragment";
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
/* Inflate the layout for this fragment */
View view = inflater.inflate(R.layout.root_fragment, container, false);
FragmentTransaction transaction = getFragmentManager()
.beginTransaction();
/*
* When this container fragment is created, we fill it with our first
* "real" fragment
*/
transaction.replace(R.id.root_frame, new FirstFragment());
transaction.commit();
return view;
}
}
最后，您可以替换片段。例如，在“真实”片段中，您可以有一个按钮：
btn.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
FragmentTransaction trans = getFragmentManager()
.beginTransaction();
/*
* IMPORTANT: We use the "root frame" defined in
* "root_fragment.xml" as the reference to replace fragment
*/
trans.replace(R.id.root_frame, new SecondFragment());
/*
* IMPORTANT: The following lines allow us to add the fragment
* to the stack and return to it later, by pressing back
*/
trans.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
trans.addToBackStack(null);
trans.commit();
}
});
我开发了一个显示类似概念的示例应用程序。您可以替换ViewPager中的片段而无需更改为新的Activity。该代码可在以下网址获得：
答案 1 :(得分：0)
我假设您希望Engineering片段位于一个全新的页面上，因为您没有在ViewPagerAdapter中使用它。如果是这种情况，请在布局中使用Activity片段创建新的Engineering，然后从Activity点击启动engineeringButton。
问题是您正在尝试将您的工程片段推入R.layout.activity_departments的View层次结构中，并且（希望）没有ViewPager，因此出现错误。