Question

我正在关注developer.android.com上的公会，并已将其添加到向栏添加操作按钮的部分。然而，他们都不想出现。我查看了代码，进行了研究，甚至重新整理了整个项目，确保我一切正确。我所做的一切似乎都没有用，所以我想我会把它放在这里，让一双新鲜的（更有经验的）眼睛看着它，让我在哪里出错。

main_activity_actions.xml

    <menu xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:myfirstapp="http://schemas.android.com/apk/res-auto">
    <item android:id="@+id/action_search"
          android:icon="@drawable/ic_action_search"
          android:title="@string/action_search"
          myfirstapp:showAsAction="ifRoom" />
    <item android:id="@+id/action_settings"
          android:title="@string/action_settings"
          myfirstapp:showAsAction="never" />
</menu>

DisplayMessageActivity.java

    public class DisplayMessageActivity extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_display_message);
        Intent intent = getIntent();
        String message = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);
        TextView textView = new TextView(this);
        textView.setTextSize(40);
        textView.setText(message);
        setContentView(textView);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu)  {
        setContentView(R.layout.activity_main);
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.main_activity_actions, menu);
        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case R.id.action_search:
                //openSearch();
                return true;
            case R.id.action_settings:
                //openSettings();
                return true;
            default:
                return super.onOptionsItemSelected(item);
        }
    }
}

的AndroidManifest.xml

    <?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.myfirstapp"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="7"
        android:targetSdkVersion="18" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/Theme.AppCompat.Light.DarkActionBar" >
        <activity
            android:name=".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=".DisplayMessageActivity"
            android:label="@string/title_activity_display_message"
            android:parentActivityName=".MainActivity" > 
            <meta-data
                android:name="android.support.PARENT_ACTIVITY"
                android:value="com.example.myfirstapp.MainActivity" />
        </activity>
    </application>

</manifest>

截图 enter image description here

Answer 1

只需删除内部的setContentView(R.layout.activity_main);

即可

@Override
public boolean onCreateOptionsMenu(Menu menu)  {
    setContentView(R.layout.activity_main);
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.main_activity_actions, menu);
    return super.onCreateOptionsMenu(menu);
}

并添加return true代替return super.onCreateOptionsMenu(menu);

Answer 2

    @Override
public boolean onCreateOptionsMenu(Menu menu) {

    getMenuInflater().inflate(R.menu.main_activity_actions, menu);
    return true;
}

试试这个。它为我工作。

操作栏上没有显示任何操作按钮

2 个答案: