这是之前在ListView类中使用divider和dividerHeight参数实现的一个例子:
<ListView
android:id="@+id/activity_home_list_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:divider="@android:color/transparent"
android:dividerHeight="8dp"/>
然而,在RecyclerView类中我没有看到这样的可能性。
<android.support.v7.widget.RecyclerView
android:id="@+id/activity_home_recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scrollbars="vertical"/>
在这种情况下,是否可以定义边距和/或直接添加自定义分隔符视图到列表项的布局中,或者是否有更好的方法来实现我的目标?
如果你想为物品添加相同的空间,最简单的方法是为RecycleView添加顶部+左侧填充,为卡片物品添加右侧+底部空白。
文件dimens.xml
<resources>
<dimen name="divider">1dp</dimen>
</resources>
文件list_item.xml
<CardView
android:layout_marginBottom="@dimen/divider"
android:layout_marginRight="@dimen/divider">
...
</CardView>
文件list.xml
<RecyclerView
...
android:paddingLeft="@dimen/divider"
android:paddingTop="@dimen/divider" />
以下是我的偷懒方法,但它很有效:
将CardView包装在一个布局中,并在父布局上设置一个填充/边距来模拟分隔符,并强制将普通分隔符设置为null。
文件list_item.xml
<LinearLayout
android:id="@+id/entry_item_layout_container"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:paddingBottom="<divider_size>" > // This is the divider
<CardView
android:layout_width="<width_size>"
android:layout_height="<height_size>">
...
</CardView>
</LinearLayout
文件list.xml
<RecyclerView
android:divider="@null"
android:layout_width="<width_size>"
android:layout_height="<height_size>"
...
/>
Here is a simple hack to add a divider
Just add a background to the layout of your recycler item as follows
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@drawable/shape_border"
android:gravity="center"
android:orientation="horizontal"
android:padding="5dp">
<ImageView
android:id="@+id/imageViewContactLogo"
android:layout_width="60dp"
android:layout_height="60dp"
android:layout_marginRight="10dp"
android:src="@drawable/ic_user" />
<LinearLayout
android:id="@+id/linearLayout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="0.92"
android:gravity="center|start"
android:orientation="vertical">
<TextView
android:id="@+id/textViewContactName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:singleLine="true"
android:text="Large Text"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="@+id/textViewStatusOrNumber"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="5dp"
android:singleLine="true"
android:text=""
android:textAppearance="?android:attr/textAppearanceMedium" />
</LinearLayout>
<TextView
android:id="@+id/textViewUnreadCount"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="10dp"
android:padding="5dp"
android:text=""
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="@color/red"
android:textSize="22sp" />
<Button
android:id="@+id/buttonInvite"
android:layout_width="54dp"
android:layout_height="wrap_content"
android:background="@drawable/ic_add_friend" />
</LinearLayout>
在drawable文件夹中创建以下shape_border.xml文件:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle" >
<gradient
android:angle="270"
android:centerColor="@android:color/transparent"
android:centerX="0.01"
android:startColor="#000" />
</shape>
这是最终的结果-一个带分隔符的RecyclerView。
实现它自己的RecyclerView版本。ItemDecoration
public class SpacingItemDecoration extends RecyclerView.ItemDecoration {
private int spacingPx;
private boolean addStartSpacing;
private boolean addEndSpacing;
public SpacingItemDecoration(int spacingPx) {
this(spacingPx, false, false);
}
public SpacingItemDecoration(int spacingPx, boolean addStartSpacing, boolean addEndSpacing) {
this.spacingPx = spacingPx;
this.addStartSpacing = addStartSpacing;
this.addEndSpacing = addEndSpacing;
}
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
super.getItemOffsets(outRect, view, parent, state);
if (spacingPx <= 0) {
return;
}
if (addStartSpacing && parent.getChildLayoutPosition(view) < 1 || parent.getChildLayoutPosition(view) >= 1) {
if (getOrientation(parent) == LinearLayoutManager.VERTICAL) {
outRect.top = spacingPx;
} else {
outRect.left = spacingPx;
}
}
if (addEndSpacing && parent.getChildAdapterPosition(view) == getTotalItemCount(parent) - 1) {
if (getOrientation(parent) == LinearLayoutManager.VERTICAL) {
outRect.bottom = spacingPx;
} else {
outRect.right = spacingPx;
}
}
}
private int getTotalItemCount(RecyclerView parent) {
return parent.getAdapter().getItemCount();
}
private int getOrientation(RecyclerView parent) {
if (parent.getLayoutManager() instanceof LinearLayoutManager) {
return ((LinearLayoutManager) parent.getLayoutManager()).getOrientation();
} else {
throw new IllegalStateException("SpacingItemDecoration can only be used with a LinearLayoutManager.");
}
}
}