我一直在遵循 android 抽屉导航指南，一切顺利，直到我尝试从列表中的项目启动 Activity 。抽屉似乎工作正常，因为我创建的测试 toast 消息在单击第一个项目时执行，但是在单击第二个项目时应用程序崩溃。
任何人都可以告诉我问题是什么，或者任何人都可以指出正确的方向..
这是我的主要 Activity :
public class MainActivity extends Activity {
private DrawerLayout mDrawerLayout;
private ListView mDrawerList;
private ActionBarDrawerToggle mDrawerToggle;
private CharSequence mDrawerTitle;
private CharSequence mTitle;
private String[] mGalaxyTitles;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTitle = mDrawerTitle = getTitle();
mGalaxyTitles = getResources().getStringArray(R.array.list_items);
mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
mDrawerList = (ListView) findViewById(R.id.left_drawer);
mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START);
mDrawerList.setAdapter(new ArrayAdapter<String>(this,
R.layout.drawer_list_item, mGalaxyTitles));
mDrawerList.setOnItemClickListener(new DrawerItemClickListener());
if (savedInstanceState == null) {
selectItem(0);}
getActionBar().setDisplayHomeAsUpEnabled(true);
getActionBar().setHomeButtonEnabled(true);
mDrawerToggle = new ActionBarDrawerToggle(
this,
mDrawerLayout,
R.drawable.ic_drawer,
R.string.hello_world,
R.string.hello_world
) {
public void onDrawerClosed(View view) {
getActionBar().setTitle(mTitle);
invalidateOptionsMenu();
}
public void onDrawerOpened(View drawerView) {
getActionBar().setTitle(mDrawerTitle);
invalidateOptionsMenu();
}
};
mDrawerLayout.setDrawerListener(mDrawerToggle);
/** if (savedInstanceState == null) {
selectItem(0);
}**/
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.main, menu);
return super.onCreateOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if (mDrawerToggle.onOptionsItemSelected(item)) {
return true;
}
return super.onOptionsItemSelected(item);}
private class DrawerItemClickListener implements ListView.OnItemClickListener {
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
switch(position) {
case 0:
Toast.makeText(getApplicationContext(), "Some Activities MAY take time to load. Please be Patient.", Toast.LENGTH_LONG).show();
//Intent a = new Intent(MainActivity.this, Dev_team.class);
//startActivity(a);
break;
case 1:
Toast.makeText(getApplicationContext(), "Some Activities MAY take time to load. Please be Patient.", Toast.LENGTH_LONG).show();
Intent a = new Intent(getBaseContext(), dev.class);
startActivity(a);
break;
default:
}
}
}
public void selectItem(int position) {
switch(position) {
case 0:
Toast.makeText(getApplicationContext(), "Some Activities MAY take time to load. Please be Patient.", Toast.LENGTH_LONG).show();
//Intent a = new Intent(MainActivity.this, Dev_team.class);
//startActivity(a);
break;
case 1:
setContentView(R.layout.dev_team);
break;
default:
}
}
@Override
public void setTitle(CharSequence title) {
mTitle = title;
getActionBar().setTitle(mTitle);
}
@Override
protected void onPostCreate(Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
mDrawerToggle.syncState();
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
mDrawerToggle.onConfigurationChanged(newConfig);
}
/**public static class GalaxyFragment extends Fragment {
public static final String ARG_Galaxy_NUMBER = "Galaxy_number";
public GalaxyFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_Galaxy, container, false);
int i = getArguments().getInt(ARG_Galaxy_NUMBER);
String Galaxy = getResources().getStringArray(R.array.list_items)[i];
int imageId = getResources().getIdentifier(Galaxy.toLowerCase(Locale.getDefault()),
"drawable", getActivity().getPackageName());
((ImageView) rootView.findViewById(R.id.image)).setImageResource(imageId);
getActivity().setTitle(Galaxy);
return rootView;
}**/
}
这是 activity_main.xml
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- The main content view -->
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/textView1"
android:layout_centerHorizontal="true"
android:layout_marginTop="30dp"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="@string/hello_world"
android:textSize="18sp" />
</RelativeLayout>
<!-- The navigation drawer -->
<ListView android:id="@+id/left_drawer"
android:layout_width="240dp"
android:layout_height="match_parent"
android:layout_gravity="start"
android:choiceMode="singleChoice"
android:divider="@android:color/transparent"
android:dividerHeight="0dp"
android:background="#111"/>
</android.support.v4.widget.DrawerLayout>
这是 dev.java
public class dev extends MainActivity{
public void onCreate(Bundle savedInstanceState){
setContentView(R.layout.dev_team);
}
}
正如 Pavel Dudka 所建议的，这是 logcat
06-25 12:05:12.815: E/Trace(778): error opening trace file: No such file or directory (2)
06-25 12:05:13.736: D/dalvikvm(778): GC_FOR_ALLOC freed 100K, 8% free 2668K/2888K, paused 174ms, total 182ms
06-25 12:05:13.746: I/dalvikvm-heap(778): Grow heap (frag case) to 3.792MB for 1127536-byte allocation
06-25 12:05:13.865: D/dalvikvm(778): GC_FOR_ALLOC freed 2K, 6% free 3767K/3992K, paused 120ms, total 120ms
06-25 12:05:13.925: D/dalvikvm(778): GC_CONCURRENT freed 1K, 5% free 3800K/3992K, paused 12ms+12ms, total 54ms
06-25 12:05:14.296: I/Choreographer(778): Skipped 33 frames! The application may be doing too much work on its main thread.
06-25 12:05:14.366: D/gralloc_goldfish(778): Emulator without GPU emulation detected.
06-25 12:05:24.766: D/AndroidRuntime(778): Shutting down VM
06-25 12:05:24.766: W/dalvikvm(778): threadid=1: thread exiting with uncaught exception (group=0x40a71930)
06-25 12:05:24.786: E/AndroidRuntime(778): FATAL EXCEPTION: main
06-25 12:05:24.786: E/AndroidRuntime(778): android.content.ActivityNotFoundException: Unable to find explicit activity class {com.example.navdraw/com.example.navdraw.dev}; have you declared this activity in your AndroidManifest.xml?
06-25 12:05:24.786: E/AndroidRuntime(778): at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:1618)
06-25 12:05:24.786: E/AndroidRuntime(778): at android.app.Instrumentation.execStartActivity(Instrumentation.java:1417)
06-25 12:05:24.786: E/AndroidRuntime(778): at android.app.Activity.startActivityForResult(Activity.java:3370)
06-25 12:05:24.786: E/AndroidRuntime(778): at android.app.Activity.startActivityForResult(Activity.java:3331)
06-25 12:05:24.786: E/AndroidRuntime(778): at android.app.Activity.startActivity(Activity.java:3566)
06-25 12:05:24.786: E/AndroidRuntime(778): at android.app.Activity.startActivity(Activity.java:3534)
06-25 12:05:24.786: E/AndroidRuntime(778): at com.example.navdraw.MainActivity$DrawerItemClickListener.onItemClick (MainActivity.java:129)
06-25 12:05:24.786: E/AndroidRuntime(778): at android.widget.AdapterView.performItemClick(AdapterView.java:298)
06-25 12:05:24.786: E/AndroidRuntime(778): at android.widget.AbsListView.performItemClick(AbsListView.java:1100)
06-25 12:05:24.786: E/AndroidRuntime(778): at android.widget.AbsListView$PerformClick.run(AbsListView.java:2749)
06-25 12:05:24.786: E/AndroidRuntime(778): at android.widget.AbsListView$1.run(AbsListView.java:3423)
06-25 12:05:24.786: E/AndroidRuntime(778): at android.os.Handler.handleCallback(Handler.java:725)
06-25 12:05:24.786: E/AndroidRuntime(778): at android.os.Handler.dispatchMessage(Handler.java:92)
06-25 12:05:24.786: E/AndroidRuntime(778): at android.os.Looper.loop(Looper.java:137)
06-25 12:05:24.786: E/AndroidRuntime(778): at android.app.ActivityThread.main(ActivityThread.java:5041)
06-25 12:05:24.786: E/AndroidRuntime(778): at java.lang.reflect.Method.invokeNative(Native Method)
06-25 12:05:24.786: E/AndroidRuntime(778): at java.lang.reflect.Method.invoke(Method.java:511)
06-25 12:05:24.786: E/AndroidRuntime(778): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
06-25 12:05:24.786: E/AndroidRuntime(778): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
06-25 12:05:24.786: E/AndroidRuntime(778): at dalvik.system.NativeStart.main(Native Method)
如果我遗漏了一些明显的东西，请告诉我，因为我是应用程序开发社区的新手。
非常感谢任何帮助。
谢谢!
最佳答案
好吧，logcat 说您还没有在 Manifest 文件中声明您的 Activity (您尝试启动的 Activity )。 Android 应用程序中的所有 Activity 都必须在 AndroidManifest.xml 文件中声明
您需要做的是将以下部分添加到您的 list 中(application 标记内的某处):
<application ...>
<activity
android:name="com.example.navdraw.dev"
android:label="label"/>
</application>
有关 list 文件结构的更多信息，您可以找到 here
关于android - 无法从抽屉导航启动 Activity ，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/17285081/