Question

我无法从我的主要活动切换到listactivity，我通过观看视频教程创建了listactivity并按照相同的步骤但是只要我点击按钮切换到菜单我就会收到错误“不幸的是，该计划已停止工作“

Button button1; 
    button1 = (Button)findViewById(R.id.but1);


    button1.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View arg0) {
            // TODO Auto-generated method stub
            Intent i = new Intent(MainActivity.this,Menu.class);
            startActivity(i);

Menu类如下：

public class Menu extends ListActivity{
String classes[] = {"First","Second","Third"};

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setListAdapter(new ArrayAdapter<String>(Menu.this,android.R.layout.simple_list_item_1, classes));
}

@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
    // TODO Auto-generated method stub
    super.onListItemClick(l, v, position, id);
    String cheese=classes[position];
    try{
    Class ourClass=Class.forName("com.ashsoft.basiccprogram." + cheese);
    Intent ourIntent=new Intent(Menu.this,ourClass);
    startActivity(ourIntent);
    }catch(ClassNotFoundException e){

        e.printStackTrace();
    }

Logcat：

Log file : `01-13 13:53:03.481: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:03.481: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:03.481: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:04.511: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:04.521: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:05.602: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:05.602: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:05.681: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:05.771: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:06.001: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:06.071: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:06.071: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:06.181: I/Choreographer(1400): Skipped 68 frames!  The application may be doing too much work on its main thread.
01-13 13:53:06.362: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:06.442: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:06.491: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:06.501: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:06.511: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:06.532: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:06.581: D/gralloc_goldfish(1400): Emulator without GPU emulation detected.
01-13 13:53:06.702: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:06.851: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:16.741: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:16.782: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:16.801: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:16.801: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:16.872: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:16.911: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:16.931: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:16.951: W/Trace(1400): Unexpected value from nativeGetEnabledTags: 0
01-13 13:53:17.052: D/AndroidRuntime(1400): Shutting down VM
01-13 13:53:17.052: W/dalvikvm(1400): threadid=1: thread exiting with uncaught exception (group=0x40a70930)
01-13 13:53:17.151: E/AndroidRuntime(1400): FATAL EXCEPTION: main
01-13 13:53:17.151: E/AndroidRuntime(1400): android.content.ActivityNotFoundException: Unable to find explicit activity class {com.ashsoft.basiccprogram/android.view.Menu}; have you declared this activity in your AndroidManifest.xml?
01-13 13:53:17.151: E/AndroidRuntime(1400):     at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:1618)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at android.app.Instrumentation.execStartActivity(Instrumentation.java:1417)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at android.app.Activity.startActivityForResult(Activity.java:3370)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at android.app.Activity.startActivityForResult(Activity.java:3331)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at android.app.Activity.startActivity(Activity.java:3566)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at android.app.Activity.startActivity(Activity.java:3534)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at com.ashsoft.basiccprogram.MainActivity$1.onClick(MainActivity.java:27)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at android.view.View.performClick(View.java:4202)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at android.view.View$PerformClick.run(View.java:17340)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at android.os.Handler.handleCallback(Handler.java:725)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at android.os.Handler.dispatchMessage(Handler.java:92)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at android.os.Looper.loop(Looper.java:137)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at android.app.ActivityThread.main(ActivityThread.java:5039)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at java.lang.reflect.Method.invokeNative(Native Method)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at java.lang.reflect.Method.invoke(Method.java:511)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
01-13 13:53:17.151: E/AndroidRuntime(1400):     at dalvik.system.NativeStart.main(Native Method)
01-13 13:53:25.911: I/Process(1400): Sending signal. PID: 1400 SIG: 9
`

清单代码：

<application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <activity
        android:name="com.ashsoft.basiccprogram.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.ashsoft.basiccprogram.First"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.FIRST" />

            <category android:name="android.intent.category.DEFAULT" />
        </intent-filter>
    </activity>
        <activity
        android:name="com.ashsoft.basiccprogram.Menu"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MENU" />

            <category android:name="android.intent.category.DEFAULT" />
        </intent-filter>
    </activity>


</application>

我使用的教程没有使用任何xml文件作为列表。

主要问题是列表没有显示出来。每当我点击主要活动的菜单按钮时，它就会停止工作。

Answer 1

您似乎尚未在清单文件中注册该Menu类。

如果它仍然不起作用，请发布logcat，以便有可能编辑我的答案。

修改

首先，你的漫长过程任务必须以asynctask为基础。

暂时让我们离开。试试这个：

<application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name="com.ashsoft.basiccprogram.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.ashsoft.basiccprogram.First" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.FIRST" /> <category android:name="android.intent.category.DEFAULT" /> </intent-filter> </activity> <activity android:name=".ListScreenActivity" android:label="@string/app_name" > </activity>

您的ListScreenActivity：

public class ListScreenActivity extends ListActivity{ String classes[] = {"First","Second","Third"}; @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); setListAdapter(new ArrayAdapter<String>(ListScreenActivity.this,android.R.layout.simple_list_item_1, classes)); ListView listView = getListView(); listView.setTextFilterEnabled(true); listView.setOnItemClickListener(new OnItemClickListener() { public void onItemClick(AdapterView<?> parent, View view, int position, long id) { //show toast Toast.makeText(getApplicationContext(),"Clicked on "+classes[position], Toast.LENGTH_SHORT).show(); } }); }

无法从主活动切换到列表视图

1 个答案: