你好，我在几个小时的过程中一直在努力解决这些错误，但无济于事。我试图将数据从我的活动传递到片段，但没有成功。我猜它在<fragment>文件中抱怨activity_second.xml。我的猜测可能是错的。有没有人遇到过这个错误？但我不知道如何解决这个错误。有些人请指导我做错了什么。以下是我的代码：
first_fragment.xml：
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/fragmentPic" >
<TextView
android:id="@+id/textName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/users_FirstName"
android:textSize="@dimen/font_size"
android:layout_gravity="center_horizontal"/>
<com.facebook.login.widget.ProfilePictureView
android:id="@+id/profilePic"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
>
</com.facebook.login.widget.ProfilePictureView>
</LinearLayout>
FirstFragment.java：
public class FirstFragment extends Fragment {
private ProfilePictureView profilePictureView;
private TextView textView;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// return super.onCreateView(inflater, container, savedInstanceState);
View rootView = inflater.inflate(R.layout.first_fragment, container, false);
Bundle bundle = new Bundle();
bundle = this.getArguments();
String profileId = bundle.getString("profileId"); //complains here and returns null
TextView textView = (TextView)rootView.findViewById(R.id.textName);
textView.setText(bundle.getString("names"));
return rootView;
}
}
activity_second.xml：
<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"
android:background="@color/backgroundColor"
>
<include android:id="@+id/toolBar"
layout="@layout/toolbar" />
<android.support.v4.widget.DrawerLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/drawer">
<fragment
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:layout="@layout/first_fragment"
class="edu.sjsu.cmpe277.termproject.Fragments.FirstFragment"
android:id="@+id/fragment1"
/>
</android.support.v4.widget.DrawerLayout>
</LinearLayout>
secondActivity.java：
public class secondActivity extends AppCompatActivity {
private Intent intent;
private Toolbar toolbar;
private String firstName, profileId;
private FirstFragment firstFragment;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_second);
intent = getIntent();
firstName = intent.getStringExtra("firstName");
profileId = intent.getStringExtra("Id");
toolbar = (Toolbar)findViewById(R.id.toolBar);
setSupportActionBar(toolbar);
toolbar.setLogo(R.drawable.ic_menu_image);
getSupportActionBar().setDisplayShowHomeEnabled(true);
getSupportActionBar().setDisplayShowTitleEnabled(false);
firstFragment = new FirstFragment();
Bundle bundle = new Bundle();
bundle.putString("names", firstName);
bundle.putString("profileId", profileId);
firstFragment.setArguments(bundle);
FragmentManager manager = getSupportFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
transaction.add(R.id.drawer, firstFragment,"newFrag").commit();
}
@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_second, 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.
switch(item.getItemId()) {
case android.R.id.home:
Intent homeIntent = new Intent(this, secondActivity.class );
homeIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(homeIntent);
}
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
以下错误：
29 01:50:11.402 13536-13536/edu.sjsu.cmpe277.termproject E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: edu.sjsu.cmpe277.termproject, PID: 13536
java.lang.RuntimeException: Unable to start activity ComponentInfo{edu.sjsu.cmpe277.termproject/edu.sjsu.cmpe277.termproject.secondActivity}: android.view.InflateException: Binary XML file line #82: Error inflating class fragment
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2693)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2758)
at android.app.ActivityThread.access$900(ActivityThread.java:177)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1448)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:5942)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
Caused by: android.view.InflateException: Binary XML file line #82: Error inflating class fragment
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:770)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:813)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:821)
at android.view.LayoutInflater.inflate(LayoutInflater.java:511)
at android.view.LayoutInflater.inflate(LayoutInflater.java:415)
at android.view.LayoutInflater.inflate(LayoutInflater.java:366)
at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:255)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:109)
at edu.sjsu.cmpe277.termproject.secondActivity.onCreate(secondActivity.java:43)
at android.app.Activity.performCreate(Activity.java:6289)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2646)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2758)
at android.app.ActivityThread.access$900(ActivityThread.java:177)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1448)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:5942)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.os.Bundle.getString(java.lang.String)' on a null object reference
at edu.sjsu.cmpe277.termproject.Fragments.FirstFragment.onCreateView(FirstFragment.java:44)
at android.support.v4.app.Fragment.performCreateView(Fragment.java:1962)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:995)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1185)
at android.support.v4.app.FragmentManagerImpl.addFragment(FragmentManager.java:1287)
at android.support.v4.app.FragmentManagerImpl.onCreateView(FragmentManager.java:2243)
at android.support.v4.app.FragmentController.onCreateView(FragmentController.java:111)
at android.support.v4.app.FragmentActivity.dispatchFragmentsOnCreateView(FragmentActivity.java:278)
at android.support.v4.app.BaseFragmentActivityHoneycomb.onCreateView(BaseFragmentActivityHoneycomb.java:31)
at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:78)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:740)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:813)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:821)
at android.view.LayoutInflater.inflate(LayoutInflater.java:511)
at android.view.LayoutInflater.inflate(LayoutInflater.java:415)
at android.view.LayoutInflater.inflate(LayoutInflater.java:366)
at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:255)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:109)
at edu.sjsu.cmpe277.termproject.secondActivity.onCreate(secondActivity.java:43)
at android.app.Activity.performCreate(Activity.java:6289)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2646)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2758)
at android.app.ActivityThread.access$900(ActivityThread.java:177)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1448)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:5942)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
答案 0 :(得分：1)
摆脱
Activity并仅使用您在Bundle中使用的明确交易。您无法通过Fragment，在布局中声明{{1}}，并尝试访问它，导致您的应用崩溃
答案 1 :(得分：0)
在activity_second.xml文件中，更改：
class="edu.sjsu.cmpe277.termproject.Fragments.FirstFragment"
到
android:name="edu.sjsu.cmpe277.termproject.Fragments.FirstFragment"
这是正确的使用前缀。