Question

我想打开片段，当点击菜单项，但它不工作，我不知道为什么。我试图调试，但没有任何帮助。如果有人可以提供帮助，我会很高兴的。提前谢谢。

menu_main.xml

var book1Name = Book1.Name;
var book2Name = Book2.Name;

MainActivity.class

<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
tools:context="com.lineup.android.webbrowser.activities.MainActivity">
<item
    android:id="@+id/clear_spinner"
    android:icon="@drawable/ic_clear"
    android:orderInCategory="50"
    android:title="Clear"
    app:showAsAction="collapseActionView|ifRoom" />
<item
    android:id="@+id/action_menu"
    android:icon="@drawable/ic_menu"
    android:orderInCategory="200"
    android:title="@string/menu"
    app:showAsAction="always">
    <menu>
        <item
            android:id="@+id/downloads"
            android:title="@string/downloads"
            android:icon="@drawable/ic_download"/>
        <item
            android:id="@+id/draw"
            android:title="@string/draw"
            android:icon="@drawable/ic_paint"/>
        <item
            android:id="@+id/history"
            android:title="@string/history"
            android:icon="@drawable/ic_action_clock"/>
        <item
            android:id="@+id/settings"
            android:title="@string/settings"
            android:icon="@drawable/ic_settings"/>
    </menu>
</item>
<item
    android:id="@+id/action_search"
    android:icon="@drawable/ic_search"
    android:orderInCategory="100"
    android:title="Search"
    app:actionViewClass="android.support.v7.widget.SearchView"
    app:showAsAction="collapseActionView|ifRoom" />

DownloadsFragment.class

 @Override
public boolean onCreateOptionsMenu(Menu menu) {
    super.onCreateOptionsMenu(menu);
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.menu_main, menu);
    return true;
}


@Override
public boolean onOptionsItemSelected(MenuItem item) {
    int id = item.getItemId();
    switch (id) {
        case R.id.downloads:
            DownloadsFragment dlfrag = new DownloadsFragment();
            getSupportFragmentManager().beginTransaction()
                    .add(R.id.container, dlfrag)
                    .commit();
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}

}

Answer 1

在onCreate方法中添加setHasOptionsMenu(true);

Answer 2

return super.onCreateView(inflater, container, savedInstanceState);

您需要退回view此处

onOptionsItemSelected（）方法在android中不起作用

2 个答案: