1

我似乎无法从选项菜单项打开新视图。程序在将意图和侦听器应用于项目时不断崩溃。我才刚刚开始，所以请善待。

当前视图是mnfsms，而我试图打开的视图是mnfsms_settings。我正在为 1.5 开发。

有人可以帮我让菜单正常工作吗？

菜单（称为 options_menu.xml）：

<menu xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:id="@+id/settings_button"
          android:title="Settings"
          android:icon="@android:drawable/ic_menu_preferences" />
    <item android:id="@+id/about_button"
          android:title="About"
          android:icon="@android:drawable/ic_menu_myplaces" />
</menu>

主视图（称为 mnfsms.java）：

package com.example.mnfsms;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;

public class mnfsms extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    /*        OnClickListener myocl = new View.OnClickListener() {
 public void onClick(View v){
  Intent myi = new Intent(mnfsms.this, mnfsms_settings.class);
  startActivity(myi);
 }
};*/    
}

public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.options_menu, menu);

    MenuItem mi_settings = (MenuItem)findViewById(R.id.settings_button);
    mi_settings.setIntent(new Intent(this, mnfsms_settings.class));

    return true;
}
}

清单：

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="com.example.mnfsms"
          android:versionCode="1"
          android:versionName="1.0">
        <application android:icon="@drawable/icon" android:label="@string/app_name">
            <activity android:name=".mnfsms" android:label="@string/main_window_name">
                <intent-filter>
                    <action android:name="android.intent.action.MAIN" />
                    <category android:name="android.intent.category.LAUNCHER" />
                </intent-filter>
            </activity>
      <activity android:name=".mnfsms_settings" android:label="string/main_window_name">
            </activity>
        </application>
        <uses-sdk android:minSdkVersion="3" />
</manifest>

堆栈跟踪：

01-06 15:07:58.045: ERROR/AndroidRuntime(2123): Uncaught handler: thread main exiting due to uncaught exception
01-06 15:07:58.055: ERROR/AndroidRuntime(2123): java.lang.NullPointerException
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at com.example.mnfsms.mnfsms.onCreateOptionsMenu(mnfsms.java:30)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at android.app.Activity.onCreatePanelMenu(Activity.java:2038)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at com.android.internal.policy.impl.PhoneWindow.preparePanel(PhoneWindow.java:421)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at com.android.internal.policy.impl.PhoneWindow.onKeyDownPanel(PhoneWindow.java:664)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at com.android.internal.policy.impl.PhoneWindow.onKeyDown(PhoneWindow.java:1278)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:1735)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at android.view.ViewRoot.deliverKeyEventToViewHierarchy(ViewRoot.java:2188)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at android.view.ViewRoot.handleFinishedEvent(ViewRoot.java:2158)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at android.view.ViewRoot.handleMessage(ViewRoot.java:1490)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at android.os.Handler.dispatchMessage(Handler.java:99)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at android.os.Looper.loop(Looper.java:123)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at android.app.ActivityThread.main(ActivityThread.java:3948)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at java.lang.reflect.Method.invokeNative(Native Method)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at java.lang.reflect.Method.invoke(Method.java:521)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:782)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:540)
01-06 15:07:58.055: ERROR/AndroidRuntime(2123):     at dalvik.system.NativeStart.main(Native Method)
4

3 回答 3

3

用findViewById_menu.findItem

于 2010-01-06T06:47:18.890 回答
0

您的代码和 XML 看起来差不多。但是，您并没有super.onCreateOptionsMenu()在方法开始时调用。

您可以发布应用程序崩溃时获得的堆栈跟踪吗？它在什么时候崩溃？当您Menu在此活动中按时？

于 2010-01-06T03:34:11.150 回答
-1

您可以使用 MenuItem mi_settings = menu.getItem(0) 而不是 MenuItem mi_settings = (MenuItem)findViewById(R.id.settings_button); 这是工作发现。

于 2010-01-06T08:28:57.233 回答