具有固定数量子项的java CardView

1 月，1 周 Questions & Answers 1239

我想要一个活动，显示正好四张卡片（从来没有更多或更少），具有与下图中相同的布局。我是否可以在不使用imo相当复杂的RecyclerView和just copy&；粘贴xml四次？同样重要的是，我可以通过id访问和更改每个视图

我现在有四个卡片视图堆叠在一起，感觉很不对。我应该怎么做

下面是我在上面的模型中使用的糟糕的XML代码。我把它放在一个片段中，因为它相当长，可能对问题不太重要：

<?xml version="1.0" encoding="utf-8"?>
<安卓.support.constraint.ConstraintLayout
    xmlns:安卓="http://schemas.安卓.com/apk/res/安卓"
    xmlns:app="http://schemas.安卓.com/apk/res-auto"
    xmlns:tools="http://schemas.安卓.com/tools"
    安卓:layout_width="match_parent"
    安卓:layout_height="match_parent"
    tools:context=".LobbyActivity">

    <安卓.support.v7.widget.CardView
        安卓:id="@+id/player1"
        安卓:layout_width="0dp"
        安卓:layout_height="wrap_content"
        安卓:layout_gravity="center"
        安卓:layout_marginBottom="16dp"
        app:layout_constraintBottom_toTopOf="@id/player2"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_chainStyle="packed"
        app:layout_constraintWidth_percent="0.95">

        <安卓.support.constraint.ConstraintLayout
            xmlns:app="http://schemas.安卓.com/apk/res-auto"
            安卓:layout_width="match_parent"
            安卓:layout_height="wrap_content">

            <TextView
                安卓:id="@+id/player1Info"
                安卓:layout_width="0dp"
                安卓:layout_height="wrap_content"
                安卓:layout_marginStart="16dp"
                安卓:layout_marginTop="24dp"
                安卓:layout_marginEnd="16dp"
                安卓:text="Playername - 100(+3)"
                安卓:textAppearance="@style/TextAppearance.AppCompat.Headline"
                安卓:textColor="@color/colorPrimary"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toEndOf="@+id/player1Thumb"
                app:layout_constraintTop_toTopOf="parent" />

            <TextView
                安卓:id="@+id/player1Ready"
                安卓:layout_width="0dp"
                安卓:layout_height="wrap_content"
                安卓:layout_marginStart="16dp"
                安卓:layout_marginTop="16dp"
                安卓:layout_marginEnd="16dp"
                安卓:text="Ready: true"
                安卓:textAppearance="@style/TextAppearance.AppCompat.Body1"
                安卓:textColor="#8A000000"
                安卓:textSize="18sp"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toEndOf="@+id/player1Thumb"
                app:layout_constraintTop_toBottomOf="@+id/player1Info" />

            <ImageView
                安卓:id="@+id/player1Thumb"
                安卓:layout_width="80dp"
                安卓:layout_height="80dp"
                安卓:layout_marginStart="16dp"
                安卓:layout_marginTop="16dp"
                安卓:layout_marginBottom="16dp"
                app:layout_constraintBottom_toBottomOf="parent"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toTopOf="parent"
                app:srcCompat="@安卓:drawable/ic_lock_lock" />

        </安卓.support.constraint.ConstraintLayout>
    </安卓.support.v7.widget.CardView>

    <安卓.support.v7.widget.CardView
        安卓:id="@+id/player2"
        安卓:layout_width="0dp"
        安卓:layout_height="wrap_content"
        安卓:layout_gravity="center"
        安卓:layout_marginBottom="16dp"
        app:layout_constraintBottom_toTopOf="@id/player3"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/player1"
        app:layout_constraintVertical_chainStyle="packed"
        app:layout_constraintWidth_percent="0.95">

        <安卓.support.constraint.ConstraintLayout xmlns:app="http://schemas.安卓.com/apk/res-auto"
            安卓:layout_width="match_parent"
            安卓:layout_height="wrap_content">

            <TextView
                安卓:id="@+id/player2Info"
                安卓:layout_width="0dp"
                安卓:layout_height="wrap_content"
                安卓:layout_marginStart="16dp"
                安卓:layout_marginTop="24dp"
                安卓:layout_marginEnd="16dp"
                安卓:text="Playername - 100(+3)"
                安卓:textAppearance="@style/TextAppearance.AppCompat.Headline"
                安卓:textColor="@color/colorPrimary"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toEndOf="@+id/player2Thumb"
                app:layout_constraintTop_toTopOf="parent" />

            <TextView
                安卓:id="@+id/player2Ready"
                安卓:layout_width="0dp"
                安卓:layout_height="wrap_content"
                安卓:layout_marginStart="16dp"
                安卓:layout_marginTop="16dp"
                安卓:layout_marginEnd="16dp"
                安卓:text="Ready: true"
                安卓:textAppearance="@style/TextAppearance.AppCompat.Body1"
                安卓:textColor="#8A000000"
                安卓:textSize="18sp"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toEndOf="@+id/player2Thumb"
                app:layout_constraintTop_toBottomOf="@+id/player2Info" />

            <ImageView
                安卓:id="@+id/player2Thumb"
                安卓:layout_width="80dp"
                安卓:layout_height="80dp"
                安卓:layout_marginStart="16dp"
                安卓:layout_marginTop="16dp"
                安卓:layout_marginBottom="16dp"
                app:layout_constraintBottom_toBottomOf="parent"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toTopOf="parent"
                app:srcCompat="@安卓:drawable/ic_lock_lock" />

        </安卓.support.constraint.ConstraintLayout>
    </安卓.support.v7.widget.CardView>

    <安卓.support.v7.widget.CardView
        安卓:id="@+id/player3"
        安卓:layout_width="0dp"
        安卓:layout_height="wrap_content"
        安卓:layout_gravity="center"
        安卓:layout_marginBottom="16dp"
        app:layout_constraintBottom_toTopOf="@id/player4"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/player2"
        app:layout_constraintVertical_chainStyle="packed"
        app:layout_constraintWidth_percent="0.95">

        <安卓.support.constraint.ConstraintLayout
            xmlns:app="http://schemas.安卓.com/apk/res-auto"
            安卓:layout_width="match_parent"
            安卓:layout_height="wrap_content">

            <TextView
                安卓:id="@+id/player3Info"
                安卓:layout_width="0dp"
                安卓:layout_height="wrap_content"
                安卓:layout_marginStart="16dp"
                安卓:layout_marginTop="24dp"
                安卓:layout_marginEnd="16dp"
                安卓:text="Playername - 100(+3)"
                安卓:textAppearance="@style/TextAppearance.AppCompat.Headline"
                安卓:textColor="@color/colorPrimary"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toEndOf="@+id/player3Thumb"
                app:layout_constraintTop_toTopOf="parent" />

            <TextView
                安卓:id="@+id/player3Ready"
                安卓:layout_width="0dp"
                安卓:layout_height="wrap_content"
                安卓:layout_marginStart="16dp"
                安卓:layout_marginTop="16dp"
                安卓:layout_marginEnd="16dp"
                安卓:text="Ready: true"
                安卓:textAppearance="@style/TextAppearance.AppCompat.Body1"
                安卓:textColor="#8A000000"
                安卓:textSize="18sp"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toEndOf="@+id/player3Thumb"
                app:layout_constraintTop_toBottomOf="@+id/player3Info" />

            <ImageView
                安卓:id="@+id/player3Thumb"
                安卓:layout_width="80dp"
                安卓:layout_height="80dp"
                安卓:layout_marginStart="16dp"
                安卓:layout_marginTop="16dp"
                安卓:layout_marginBottom="16dp"
                app:layout_constraintBottom_toBottomOf="parent"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toTopOf="parent"
                app:srcCompat="@安卓:drawable/ic_lock_lock" />

        </安卓.support.constraint.ConstraintLayout>
    </安卓.support.v7.widget.CardView>

    <安卓.support.v7.widget.CardView
        安卓:id="@+id/player4"
        安卓:layout_width="0dp"
        安卓:layout_height="wrap_content"
        安卓:layout_gravity="center"
        安卓:layout_marginBottom="16dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/player3"
        app:layout_constraintVertical_chainStyle="packed"
        app:layout_constraintWidth_percent="0.95">

        <安卓.support.constraint.ConstraintLayout
            xmlns:app="http://schemas.安卓.com/apk/res-auto"
            安卓:layout_width="match_parent"
            安卓:layout_height="wrap_content">

            <TextView
                安卓:id="@+id/player4Info"
                安卓:layout_width="0dp"
                安卓:layout_height="wrap_content"
                安卓:layout_marginStart="16dp"
                安卓:layout_marginTop="24dp"
                安卓:layout_marginEnd="16dp"
                安卓:text="Playername - 100(+3)"
                安卓:textAppearance="@style/TextAppearance.AppCompat.Headline"
                安卓:textColor="@color/colorPrimary"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toEndOf="@+id/player4Thumb"
                app:layout_constraintTop_toTopOf="parent" />

            <TextView
                安卓:id="@+id/player4Ready"
                安卓:layout_width="0dp"
                安卓:layout_height="wrap_content"
                安卓:layout_marginStart="16dp"
                安卓:layout_marginTop="16dp"
                安卓:layout_marginEnd="16dp"
                安卓:text="Ready: true"
                安卓:textAppearance="@style/TextAppearance.AppCompat.Body1"
                安卓:textColor="#8A000000"
                安卓:textSize="18sp"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toEndOf="@+id/player4Thumb"
                app:layout_constraintTop_toBottomOf="@+id/player4Info" />

            <ImageView
                安卓:id="@+id/player4Thumb"
                安卓:layout_width="80dp"
                安卓:layout_height="80dp"
                安卓:layout_marginStart="16dp"
                安卓:layout_marginTop="16dp"
                安卓:layout_marginBottom="16dp"
                app:layout_constraintBottom_toBottomOf="parent"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toTopOf="parent"
                app:srcCompat="@安卓:drawable/ic_lock_lock" />

        </安卓.support.constraint.ConstraintLayout>
    </安卓.support.v7.widget.CardView>

</安卓.support.constraint.ConstraintLayout>

# 2 楼答案

使用LinearLayout。。。（可选）使用唯一的id属性转换为4次include

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.LinearLayoutCompat
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center_vertical"
    android:orientation="vertical">

    <android.support.design.card.MaterialCardView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp">
        <Space
            android:layout_width="match_parent"
            android:layout_height="80dp"/>
    </android.support.design.card.MaterialCardView>

    <android.support.design.card.MaterialCardView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp">
        <Space
            android:layout_width="match_parent"
            android:layout_height="80dp"/>
    </android.support.design.card.MaterialCardView>

    <android.support.design.card.MaterialCardView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp">
        <Space
            android:layout_width="match_parent"
            android:layout_height="80dp"/>
    </android.support.design.card.MaterialCardView>

    <android.support.design.card.MaterialCardView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp">
        <Space
            android:layout_width="match_parent"
            android:layout_height="80dp"/>
    </android.support.design.card.MaterialCardView>

</android.support.v7.widget.LinearLayoutCompat>

这看起来很像你在那里看到的：

共 (5) 个答案

# 1 楼答案
如果卡片视图看起来相同，您可以创建一个单独的可重用布局，其中只有一个卡片视图。然后，可以使用<include>标记将其添加4次。这样，如果你需要改变它的外观，你只需要做一次

更多关于如何实现这个here的信息

示例
```
<include 
   android:id="@+id/news_title" 
   android:layout_width="match_parent" 
   android:layout_height="match_parent" 
   layout="@layout/title"/>
```
NB:您可以通过设置id来区分每个包含的元素，就像上面的示例一样

要获取子视图，您需要它的id。首先，使用id检索视图（或CardView或…）中的一个视图。例如：
```
CardView card1 = view.findViewById(cardView1);
card1.findViewById(player1Info);
```
与下一张随附卡片相同：
```
CardView card2 = view.findViewById(cardView2);
card2.findViewById(player1Info); //Notice how it is the same id here <------  
```

# 3 楼答案

如果您正在使用RecyclerView，请使用^{}来实现这一点

List<String> dataSource = new ArrayList<String>();


RecyclerView.LayoutParams lp = new RecyclerView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
    recyclerView.setLayoutParams(lp);


    GridLayoutManager gridLayoutManager = new GridLayoutManager(this, 4, GridLayoutManager.VERTICAL, false);
    setContentView(recyclerView);
    recyclerView.setAdapter(new TextRecyclerAdapter(dataSource));
    recyclerView.setLayoutManager(gridLayoutManager);

here is git example for this

# 4 楼答案
如前所述，当您不需要额外的视图组来获得良好的UI性能时，可以使用here<merge/>

The tag helps eliminate redundant view groups in your view hierarchy when including one layout within another. For example, if your main layout is a vertical LinearLayout in which two consecutive views can be re-used in multiple layouts, then the re-usable layout in which you place the two views requires its own root view. However, using another LinearLayout as the root for the re-usable layout would result in a vertical LinearLayout inside a vertical LinearLayout. The nested LinearLayout serves no real purpose other than to slow down your UI performance.
```
<merge xmlns:android="http://schemas.android.com/apk/res/android">

<Button
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="@string/add"/>

<Button
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="@string/delete"/>

</merge>
```
Now, when you include this layout in another layout (using the <include/> tag), the system ignores the <merge> element and places the two buttons directly in the layout, in place of the <include/> tag.

希望这对你有帮助
# 5 楼答案
当然可以。在你的情况下，回收者观点不会给你带来任何好处

但不要忘记创建style或使用<include>

如果未来的设计会有所改变，这将对你有所帮助

在你的情况下，我建议使用include。你可以读一下here。主要想法是创建传统的cardview_布局。xml及其使用
```
<include layout="@layout/cardview_layout"/>
```
在主xml文件中

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有 Java 编程相关的问题?

具有固定数量子项的java CardView

共 (5) 个答案

# 1 楼答案

# 2 楼答案

# 3 楼答案

# 4 楼答案

# 5 楼答案