java 创建选项菜单。 （如果不存在，则在res文件夹中创建一个菜单目录，并在该目录中创建一个菜单资源文件

Posted 2021-05-08

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:id="@+id/action_settings"
        android:title="@string/menu_settings"/>
    <item
        android:id="@+id/action_quit"
        android:title="@string/menu_quit"/>
</menu>

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


    @Override
    public boolean onOptionsItemSelected(MenuItem item) {

        boolean handled= false;
        switch (item.getItemId()){
            case R.id.action_settings:
                Toast.makeText(MainActivity.this, "Settings clicked", Toast.LENGTH_SHORT).show();
                handled = true;
                break;
            case R.id.action_quit:
                handled = true;
                finish();
                break;
        }

        return handled;
    }