我正在尝试运行我的程序，但出现标题中列出的错误，我无法弄清楚原因
下面是我的MainActivity
package com.example.iwould;
import android.content.Context;
import android.content.res.Configuration;
import android.graphics.Color;
import android.graphics.Typeface;
import android.os.Bundle;
import android.support.v4.app.ActionBarDrawerToggle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.widget.DrawerLayout;
import android.view.LayoutInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import com.app.iwould.R;
// GOING TO HAVE TO MAKE THE BODY THE MAIN PAGE
public class MainActivity extends FragmentActivity {
private String[] mPlanetTitles;
private ListView mDrawerList;
private DrawerLayout mDrawerLayout;
private ActionBarDrawerToggle mDrawerToggle;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getActionBar().setDisplayShowCustomEnabled(true);
getActionBar().setDisplayShowTitleEnabled(false);
LayoutInflater inflator = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View v = inflator.inflate(R.layout.titleview, null);
//if you need to customize anything else about the text, do it here.
//I'm using a custom TextView with a custom font in my layout xml so all I need to do is set title
((TextView)v.findViewById(R.id.title)).setText(getTitle());
Typeface typeface = Typeface.createFromAsset(this.getAssets(), "robotomed.ttf");
((TextView)v.findViewById(R.id.title)).setTypeface(typeface);
//assign the view to the actionbar
getActionBar().setCustomView(v);
setContentView(R.layout.navdrawer);
android.support.v4.app.FragmentManager fragmentManager = getSupportFragmentManager();
android.support.v4.app.FragmentTransaction fragmentTransaction = fragmentManager
.beginTransaction();
Home fragment = new Home();
fragmentTransaction.replace(R.id.llhome, fragment);
fragmentTransaction.commit();
mPlanetTitles = getResources().getStringArray(R.array.planets_array);
mDrawerList = (ListView) findViewById(R.id.left_drawer);
CustomListAdapter listAdapter = new CustomListAdapter(MainActivity.this , R.layout.drawer_list_item , mPlanetTitles);
mDrawerList.setAdapter(listAdapter);
// Set the list's click listener
mDrawerList.setOnItemClickListener(new DrawerItemClickListener());
mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
mDrawerToggle = new ActionBarDrawerToggle(this, /* host Activity */
mDrawerLayout, /* DrawerLayout object */
R.drawable.ic_launcher, /* nav drawer icon to replace 'Up' caret */
R.string.app_name, /* "open drawer" description */
R.string.about_us /* "close drawer" description */
) {
/** Called when a drawer has settled in a completely closed state. */
public void onDrawerClosed(View view) {
getActionBar().setTitle("Home");
}
/** Called when a drawer has settled in a completely open state. */
public void onDrawerOpened(View drawerView) {
getActionBar().setTitle("StayHealthy");
}
};
// Set the drawer toggle as the DrawerListener
mDrawerLayout.setDrawerListener(mDrawerToggle);
getActionBar().setDisplayHomeAsUpEnabled(true);
getActionBar().setHomeButtonEnabled(true);
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
mDrawerToggle.onConfigurationChanged(newConfig);
}
@Override
protected void onPostCreate(Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
// Sync the toggle state after onRestoreInstanceState has occurred.
mDrawerToggle.syncState();
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Pass the event to ActionBarDrawerToggle, if it returns
// true, then it has handled the app icon touch event
if (mDrawerToggle.onOptionsItemSelected(item)) {
return true;
}
// Handle your other action bar items...
return super.onOptionsItemSelected(item);
}
@Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
finish();
}
private class DrawerItemClickListener implements
ListView.OnItemClickListener {
@Override
public void onItemClick(AdapterView parent, View view, int position,
long id) {
android.support.v4.app.FragmentManager fragmentManager = getSupportFragmentManager();
android.support.v4.app.FragmentTransaction transaction = fragmentManager
.beginTransaction();
selectItem(position);
switch (position) {
case (0):
Home HomeFragment = new Home();
// Replace whatever is in the fragment_container view with this
// fragment,
// and add the transaction to the back stack
transaction.replace(R.id.llhome, HomeFragment);
transaction.addToBackStack(null);
// Commit the transaction
transaction.commit();
mDrawerList.setItemChecked(position, true);
mDrawerLayout.closeDrawer(mDrawerList);
break;
case (1):
break;
case (2):
break;
case (3):
Toast.makeText(getApplicationContext(), "Not Configured",
Toast.LENGTH_SHORT).show();
break;
case (4):
Toast.makeText(getApplicationContext(), "Not Configured",
Toast.LENGTH_SHORT).show();
break;
}
mDrawerList.clearChoices();
}
}
/** Swaps fragments in the main content view */
private void selectItem(int position) {
}
@Override
public void setTitle(CharSequence title) {
String mTitle = "Title";
getActionBar().setTitle(mTitle);
}
private class CustomListAdapter extends ArrayAdapter {
private Context mContext;
private int id;
private String[] items ;
public CustomListAdapter(Context context, int textViewResourceId , String[] list )
{
super(context, textViewResourceId, list);
mContext = context;
id = textViewResourceId;
items = list ;
}
@Override
public View getView(int position, View v, ViewGroup parent)
{
View mView = v ;
if(mView == null){
LayoutInflater vi = (LayoutInflater)mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
mView = vi.inflate(id, null);
}
TextView text = (TextView) mView.findViewById(R.id.tvmenu);
Typeface tf = Typeface.createFromAsset(getAssets(),"aristareg.ttf");
if(items[position] != null )
{
text.setTypeface(tf);
//text.setTextColor(Color.WHITE);
text.setText(items[position]);
//text.setBackgroundColor(Color.RED);
int color = Color.rgb( 51, 153, 255);
text.setTextColor( color );
}
if(position == 3){
int color = Color.rgb( 34, 153, 34);
text.setTextColor( color );
}
return mView;
}
}
}
这是我的 list
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:myapp="http://schemas.android.com/apk/res/com.app.iWould"
package="com.app.iwould"
android:versionCode="3"
android:versionName="1.2" >
<uses-sdk
android:minSdkVersion="11"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.INTERNET" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name" >
<activity
android:name="com.example.iwould.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.google.ads.AdActivity"
android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize" />
</application>
</manifest>
下面是我的logcat
07-25 00:34:00.099: E/AndroidRuntime(4535): FATAL EXCEPTION: main
07-25 00:34:00.099: E/AndroidRuntime(4535): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.app.iwould/com.example.iwould.MainActivity}: java.lang.ClassNotFoundException: com.example.iwould.MainActivity
07-25 00:34:00.099: E/AndroidRuntime(4535): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1993)
07-25 00:34:00.099: E/AndroidRuntime(4535): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2104)
07-25 00:34:00.099: E/AndroidRuntime(4535): at android.app.ActivityThread.access$600(ActivityThread.java:132)
07-25 00:34:00.099: E/AndroidRuntime(4535): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1157)
07-25 00:34:00.099: E/AndroidRuntime(4535): at android.os.Handler.dispatchMessage(Handler.java:99)
07-25 00:34:00.099: E/AndroidRuntime(4535): at android.os.Looper.loop(Looper.java:137)
07-25 00:34:00.099: E/AndroidRuntime(4535): at android.app.ActivityThread.main(ActivityThread.java:4575)
07-25 00:34:00.099: E/AndroidRuntime(4535): at java.lang.reflect.Method.invokeNative(Native Method)
07-25 00:34:00.099: E/AndroidRuntime(4535): at java.lang.reflect.Method.invoke(Method.java:511)
07-25 00:34:00.099: E/AndroidRuntime(4535): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:789)
07-25 00:34:00.099: E/AndroidRuntime(4535): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:556)
07-25 00:34:00.099: E/AndroidRuntime(4535): at dalvik.system.NativeStart.main(Native Method)
07-25 00:34:00.099: E/AndroidRuntime(4535): Caused by: java.lang.ClassNotFoundException: com.example.iwould.MainActivity
07-25 00:34:00.099: E/AndroidRuntime(4535): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)
07-25 00:34:00.099: E/AndroidRuntime(4535): at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
07-25 00:34:00.099: E/AndroidRuntime(4535): at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
07-25 00:34:00.099: E/AndroidRuntime(4535): at android.app.Instrumentation.newActivity(Instrumentation.java:1023)
07-25 00:34:00.099: E/AndroidRuntime(4535): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1984)
07-25 00:34:00.099: E/AndroidRuntime(4535): ... 11 more
如果有人能弄清楚为什么这不起作用，那就太好了。在 MainActivity 中，我正在实现一个抽屉导航，所以我从扩展一个 Activity 到扩展一个 FragmentActivity。我认为这可能与此有关。
最佳答案
list 中的包裹
package="com.app.iwould"
&你的包裹是
com.example.iwould.MainActivity
这就是你得到“ClassNotFound”异常的原因。
关于安卓 - java.lang.RuntimeException : Unable to instantiate activity，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/17849285/