我编写了一段代码，允许用户在单击 ListView 中的项目时转到另一个 Activity 。但是发生了错误。模拟器询问我是否在 android-manifest 中添加了新的 Activity!。
我已经做到了。
我应该做什么？
这是完整的堆栈跟踪。
07-24 12:20:35.263: E/AndroidRuntime(455): FATAL EXCEPTION: main
07-24 12:20:35.263: E/AndroidRuntime(455): android.content.ActivityNotFoundException: Unable to find explicit activity class {com.example.tstnetconnwithjson/com.example.tstnetconnwithjson.tables.full}; have you declared this activity in your AndroidManifest.xml?
07-24 12:20:35.263: E/AndroidRuntime(455): at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:1404)
07-24 12:20:35.263: E/AndroidRuntime(455): at android.app.Instrumentation.execStartActivity(Instrumentation.java:1378)
07-24 12:20:35.263: E/AndroidRuntime(455): at android.app.Activity.startActivityForResult(Activity.java:2817)
07-24 12:20:35.263: E/AndroidRuntime(455): at android.app.Activity.startActivity(Activity.java:2923)
07-24 12:20:35.263: E/AndroidRuntime(455): at com.example.tstnetconnwithjson.MainActivity$conn$1.onItemClick(MainActivity.java:195)
07-24 12:20:35.263: E/AndroidRuntime(455): at android.widget.AdapterView.performItemClick(AdapterView.java:284)
07-24 12:20:35.263: E/AndroidRuntime(455): at android.widget.ListView.performItemClick(ListView.java:3382)
07-24 12:20:35.263: E/AndroidRuntime(455): at android.widget.AbsListView$PerformClick.run(AbsListView.java:1696)
07-24 12:20:35.263: E/AndroidRuntime(455): at android.os.Handler.handleCallback(Handler.java:587)
07-24 12:20:35.263: E/AndroidRuntime(455): at android.os.Handler.dispatchMessage(Handler.java:92)
07-24 12:20:35.263: E/AndroidRuntime(455): at android.os.Looper.loop(Looper.java:123)
07-24 12:20:35.263: E/AndroidRuntime(455): at android.app.ActivityThread.main(ActivityThread.java:4627)
07-24 12:20:35.263: E/AndroidRuntime(455): at java.lang.reflect.Method.invokeNative(Native Method)
07-24 12:20:35.263: E/AndroidRuntime(455): at java.lang.reflect.Method.invoke(Method.java:521)
07-24 12:20:35.263: E/AndroidRuntime(455): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
07-24 12:20:35.263: E/AndroidRuntime(455): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
07-24 12:20:35.263: E/AndroidRuntime(455): at dalvik.system.NativeStart.main(Native Method)
这是 maifest 文件:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.tstnetconnwithjson"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="15" />
<uses-permission android:name="android.permission.INTERNET"/>
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="@string/title_activity_main" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name="full"></activity>
</application>
</manifest>
这是我调用启动 Activity 的代码:
import java.util.ArrayList;
import java.util.Collection;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.conn.DefaultClientConnection;
import org.apache.http.protocol.HTTP;
import org.apache.http.util.EntityUtils;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.json.JSONTokener;
import com.example.tstnetconnwithjson.tables.custome;
import com.example.tstnetconnwithjson.tables.videos;
import android.os.AsyncTask;
import android.os.Bundle;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.app.ProgressDialog;
import android.content.DialogInterface;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
public class MainActivity extends Activity {
Button search; ;
TextView name ;
ListView listview ;
ArrayList<videos > videolist;
ArrayAdapter< videos > adapter ;
AlertDialog.Builder alert ;
ProgressDialog progressdialog ;
EditText name;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
videolist = new ArrayList<videos>();
adapter = new ArrayAdapter<videos>(this, android.R.layout.simple_list_item_1 , android.R.id.text1,videolist);
name=(EditText) findViewById(R.id.editText1);
alert = new Builder(this);
alert.setTitle("Warnning" ) ;
alert.setMessage("You want to connect to the internet ..? " );
alert.setNegativeButton("No ", null);
alert.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface arg0, int arg1) {
String username=name.getText().toString();
new connection().execute("https://gdata.youtube.com/feeds/api/videos?author="+username+"&v=2&alt=jsonc");
}
});
progressdialog = new ProgressDialog(this);
progressdialog.setMessage("Wait Loading .... ");
progressdialog.setCancelable(false);
search = (Button) findViewById(R.id.button1);
name = (TextView) findViewById(R.id.textView1);
listview = (ListView) findViewById(R.id.listView1);
listview.setAdapter(adapter);
search.setOnClickListener(new OnClickListener() {
public void onClick(View arg0) {
alert.show();
}
});
}
class connection extends AsyncTask<String, Integer, String>{
@Override
protected void onPreExecute() {
progressdialog.show();
super.onPreExecute();
}
@Override
protected String doInBackground(String... arg0) {
String s = GetUrlBody(arg0[0]);
return s;
}
@Override
protected void onPostExecute(String result) {
try{
JSONObject jo =(JSONObject) new JSONTokener(result).nextValue();
JSONObject feed = jo.optJSONObject("data");
JSONArray entry = feed.optJSONArray("items");
for(int i = 0 ; i<entry.length() ; i++){
String title = entry.getJSONObject(i).getString("title");
String thumbURL = entry.getJSONObject(i).getJSONObject("thumbnail").getString("sqDefault");
Log.d("after get image", "ok")
String url;
try {
url = entry.getJSONObject(i).getJSONObject("player").getString("mobile");
} catch (JSONException ignore) {
url = entry.getJSONObject(i).getJSONObject("player").getString("default");
}
String description = entry.getJSONObject(i).getString("description");
Log.d("after get description", "ok");
videos videoobject=new videos();
videoobject.setDecscrption(description);
videoobject.setImageurl(thumbURL);
videoobject.setVediourl(url);
videoobject.setVideoname(title);
videolist.add(videoobject);
}
listview.setAdapter(new custome(MainActivity.this,videolist));
Log.d("AFTER set custome ", "before notify changes");
adapter.notifyDataSetChanged();
lview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
videos vobject=(videos)arg0.getItemAtPosition(arg2);
Intent intent = new Intent(getApplicationContext(),full.class);
intent.putExtra("title" ,vobject.getVideoname() );
intent.putExtra("description" ,vobject.getDecscrption() );
intent.putExtra("imageURL" ,vobject.getImageurl() );
intent.putExtra("videoURL" ,vobject.getVediourl() );
startActivity(intent);
}
});
}catch(Exception exception) {
Log.d("exception ", "nock nock nock....");
Log.e("json ", exception.getMessage());
}
progressdialog.dismiss();
super.onPostExecute(result);
}
String GetUrlBody (String Url ){
HttpClient client = new DefaultHttpClient();
HttpGet gethttp = new HttpGet(Url);
try{
HttpResponse response = client.execute(gethttp);
if(response.getStatusLine().getStatusCode() == 200){
String save =
EntityUtils.toString(response.getEntity(), HTTP.UTF_8);
return save;
}else {
return "Not Found";
}
}catch(Exception exception){}
return null;
}
}
}
最佳答案
首先要注意的是: 1. 不要以如下方式启动新 Activity:
Intent intent = new Intent(getApplicationContext(),full.class);
而是:
Intent intent = new Intent(MainActivity.this, full.class);
2.您的代码甚至无法编译，因为您有两个具有相同命名的类成员: name (一个 EditText 和一个 TextView)。那么你就缺少冒号。
然后，确保full确实存在并且在 Manifest 中是正确的。 (这到底是什么类名？合法，但是 Java 的类名惯例约定应该以大写字母开头)。就像(@Sanath 的回答):
<activity android:name=".tables.full"/>或<activity android:name="com.example.tstnetconnwithjson.tables.full"/> .
然后，即使这没有帮助，也可能是由于您的 private libraries are not exported in Eclipse 。但如果你的full Activity 从兼容性包扩展FragmentActivity 。
这些是导致您的问题的可能原因。至少是我能想到的并且非常熟悉的。
关于Android list 问题，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/17834316/