小编leo*_*ian的帖子

实现此功能的最佳策略是什么:

我有一个水平的RecyclerView卡.每张卡都将实现整个屏幕,但我希望它显示下一张卡的一部分,如果它有多个项目则显示前一张卡.

我知道我可以通过android:layout_width在适配器上设置我的卡来实现这一点,使其具有250dp的特定DP而不是match_parent.但它看起来不是一个合适的解决方案.

这是我的代码:

使用RecyclerView的活动:

    class ListPokemon : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val items = createListPokemons()
        recyclerView.adapter = PokemonAdapter(items)
        recyclerView.layoutManager = LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false)
        recyclerView.setHasFixedSize(true)
        val pagerSnapHelper = PagerSnapHelper()
        pagerSnapHelper.attachToRecyclerView(recyclerView)
    }

    private fun createListPokemons(): List<Pokemon> {
        val pokemons = ArrayList<Pokemon>()
        pokemons += createPokemon("Pikachu")
        pokemons += createPokemon("Bulbasaur")
        pokemons += createPokemon("Charmander")
        pokemons += createPokemon("Squirtle")

        return pokemons
    }

    private fun createPokemon(name: String) = Pokemon(name = name, height = 1, weight = 69, id = …

我有两节课:

public class Questionnaire {

    @DatabaseField(generatedId=true, useGetSet=true)
    private Long id;

    @DatabaseField
    private int type;

    @DatabaseField
    private String title;

    @DatabaseField
    private String description;


    @ForeignCollectionField(eager = true)   
    private Collection<Question> questions; 
// Get and Set omitted

和

  public class Question {

        @DatabaseField(generatedId=true, useGetSet=true)
        private Long id;

        @DatabaseField
        private int type;

        @DatabaseField
        private String description;


        @DatabaseField(foreign = true, foreignAutoRefresh= true)
        private Questionnaire questionario;
//get and set ommited

当我用问题列表保存问卷时.对象是持久的,但我失去了关系.

我以这种方式保存:

ForeignCollection<Question> questions =
    getDao(Questionnaire.class).getEmptyForeignCollection("questions");

for(Question question : DataUtil.getAllQuestions()) {
    questions.add(question);
}

Questionnaire questionnarie = new …

我正在使用此代码创建Heads Up通知.

private static void showNotificationNew(final Context context,final String title,final String message,final Intent intent, final int notificationId, final boolean isHeaderNotification) {
    NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(context.getApplicationContext())
            .setSmallIcon(R.drawable.prime_builder_icon)
            .setPriority(Notification.PRIORITY_DEFAULT)
            .setCategory(Notification.CATEGORY_MESSAGE)
            .setContentTitle(title)
            .setContentText(message)
            .setWhen(0)
            .setTicker(context.getString(R.string.app_name));

    PendingIntent fullScreenPendingIntent = PendingIntent.getActivity(context, 0, intent, PendingIntent.FLAG_CANCEL_CURRENT);
    notificationBuilder.setContentText(message);
    if(isHeaderNotification) {
        notificationBuilder.setFullScreenIntent(fullScreenPendingIntent, false);
    }

    notificationBuilder.setContentIntent(fullScreenPendingIntent);
    notificationBuilder.setAutoCancel(true);


    Notification notification = notificationBuilder.build();
    NotificationManager manager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
    manager.notify(notificationId, notification);
}

事情是,通知应该出现占据顶部屏幕的一个好部分以引起用户注意,但是几秒钟之后它应该被解雇并且应该出现正常通知.

但是这段代码并没有这样做.通知保持占据所有顶部屏幕,直到用户解雇它.

我正在考虑使用Handler在几秒钟后使用相同的ID创建另一个正常通知,但我想知道是否有更好的方法来执行此操作.

按照WhatsApp的一个例子,模拟我想要的行为.

大家好，我正在创建一个包含行和两个按钮的 Compose 函数。我想以第一个位于屏幕开头、第二个位于边框末尾的方式对齐这些按钮。我怎样才能做到这一点？现在，我有这个：

@Composable
private fun TwoButtons() {
    Row(
        modifier = Modifier
            .fillMaxWidth()
            .background(Color.Gray),
        horizontalArrangement = Arrangement.SpaceEvenly,
        verticalAlignment = Alignment.CenterVertically
    ) {
        Button(
          onClick = { }
        )  {
            Text(text = "One")
        }

        Button(
            onClick = { }
        )  {
            Text(text = "Two")
        }

    }
}

我得到这个结果：