我正在尝试在同一布局中实现包含 RecyclerView 和 ScrollView 的布局。
布局模板:
<RelativeLayout>
<ScrollView android:id="@+id/myScrollView">
<unrelated data>...</unrealated data>
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/my_recycler_view"
/>
</ScrollView>
</RelativeLayout>
问题:我可以滚动到 ScrollView
的最后一个元素
我尝试过的事情:
ScrollView 内的卡片视图(现在 ScrollView 包含 RecyclerView) - 可以看到卡片,直到 RecyclerView 最初的想法是使用 RecyclerView 而不是 ScrollView 来实现这个 viewGroup,其中一个视图类型是 CardView 但我得到的结果与滚动视图
NestedScrollView
,因为它可以处理很多滚动问题
NestedScrollView
而不是 ScrollView
。这正是它的用途。
使用 NestedScrollView
而不是 ScrollView
请通过 NestedScrollView reference document 了解更多信息。
并将 recyclerView.setNestedScrollingEnabled(false);
添加到您的 RecyclerView
我知道我迟到了,但即使谷歌修复了 android.support.v7.widget.RecyclerView
,问题仍然存在
我现在遇到的问题是 RecyclerView
,其中 layout_height=wrap_content
没有计算 ScrollView
内所有项目的高度,仅发生在 Marshmallow 和 Nougat+(API 23、24、25)版本上。< br> (更新:用 android.support.v4.widget.NestedScrollView
替换 ScrollView
适用于所有版本。我不知何故错过了测试 accepted solution。将此作为演示添加到我的 github 项目中。)
在尝试了不同的事情之后,我找到了解决此问题的解决方法。
简而言之,这是我的布局结构:
<ScrollView>
<LinearLayout> (vertical - this is the only child of scrollview)
<SomeViews>
<RecyclerView> (layout_height=wrap_content)
<SomeOtherViews>
解决方法是将 RecyclerView
与 RelativeLayout
包装起来。不要问我是怎么找到这个解决方法的!!! ¯\_(ツ)_/¯
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:descendantFocusability="blocksDescendants">
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</RelativeLayout>
GitHub 项目 - https://github.com/amardeshbd/android-recycler-view-wrap-content 上提供了完整示例
这是一个演示截屏视频,显示了正在执行的修复:
https://github.com/amardeshbd/android-recycler-view-wrap-content/raw/master/web-resources/RecyclerView-wrap_content-demo-screen-cash.gif
虽然建议
你不应该把一个可滚动的视图放在另一个可滚动的视图中
是一个合理的建议,但是如果您在回收站视图上设置固定高度,它应该可以正常工作。
如果您知道适配器项目布局的高度,您可以计算 RecyclerView 的高度。
int viewHeight = adapterItemSize * adapterData.size();
recyclerView.getLayoutParams().height = viewHeight;
adapterItemSize
变量是什么?
如果为 RecyclerView 设置固定高度对某人(如我)不起作用,这是我添加到固定高度解决方案中的内容:
mRecyclerView.addOnItemTouchListener(new RecyclerView.OnItemTouchListener() {
@Override
public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {
int action = e.getAction();
switch (action) {
case MotionEvent.ACTION_MOVE:
rv.getParent().requestDisallowInterceptTouchEvent(true);
break;
}
return false;
}
@Override
public void onTouchEvent(RecyclerView rv, MotionEvent e) {
}
@Override
public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {
}
});
新的 Android 支持库 23.2 解决了这个问题,您现在可以将 wrap_content 设置为 RecyclerView
的高度并正常工作。
RecyclerViews 可以放入 ScrollViews,只要它们不自己滚动。在这种情况下,将其设置为固定高度是有意义的。
正确的解决方案是在 RecyclerView 高度上使用 wrap_content
,然后实现可以正确处理包装的自定义 LinearLayoutManager。
将此 LinearLayoutManager 复制到您的项目中:https://github.com/serso/android-linear-layout-manager/blob/master/lib/src/main/java/org/solovyev/android/views/llm/LinearLayoutManager.java
然后包装 RecyclerView:
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
并像这样设置它:
RecyclerView list = (RecyclerView)findViewById(R.id.list);
list.setHasFixedSize(true);
list.setLayoutManager(new com.example.myapp.LinearLayoutManager(list.getContext()));
list.setAdapter(new MyViewAdapter(data));
编辑:这可能会导致滚动复杂化,因为 RecyclerView 可以窃取 ScrollView 的触摸事件。我的解决方案是完全放弃 RecyclerView 并使用 LinearLayout,以编程方式膨胀子视图,并将它们添加到布局中。
对于 ScrollView
,您可以使用 fillViewport=true
并按如下方式制作 layout_height="match_parent"
并将回收器视图放入其中:
<ScrollView
android:fillViewport="true"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@+id/llOptions">
<android.support.v7.widget.RecyclerView
android:id="@+id/rvList"
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
</ScrollView>
无需通过代码进一步调整高度。
手动计算 RecyclerView
的高度不好,最好使用自定义 LayoutManager
。
上述问题的原因是任何具有滚动(ListView
,GridView
,RecyclerView
)的视图在添加为另一个视图中的子视图具有滚动时都无法计算其高度。所以覆盖它的 onMeasure
方法将解决这个问题。
请将默认布局管理器替换为以下内容:
public class MyLinearLayoutManager extends android.support.v7.widget.LinearLayoutManager {
private static boolean canMakeInsetsDirty = true;
private static Field insetsDirtyField = null;
private static final int CHILD_WIDTH = 0;
private static final int CHILD_HEIGHT = 1;
private static final int DEFAULT_CHILD_SIZE = 100;
private final int[] childDimensions = new int[2];
private final RecyclerView view;
private int childSize = DEFAULT_CHILD_SIZE;
private boolean hasChildSize;
private int overScrollMode = ViewCompat.OVER_SCROLL_ALWAYS;
private final Rect tmpRect = new Rect();
@SuppressWarnings("UnusedDeclaration")
public MyLinearLayoutManager(Context context) {
super(context);
this.view = null;
}
@SuppressWarnings("UnusedDeclaration")
public MyLinearLayoutManager(Context context, int orientation, boolean reverseLayout) {
super(context, orientation, reverseLayout);
this.view = null;
}
@SuppressWarnings("UnusedDeclaration")
public MyLinearLayoutManager(RecyclerView view) {
super(view.getContext());
this.view = view;
this.overScrollMode = ViewCompat.getOverScrollMode(view);
}
@SuppressWarnings("UnusedDeclaration")
public MyLinearLayoutManager(RecyclerView view, int orientation, boolean reverseLayout) {
super(view.getContext(), orientation, reverseLayout);
this.view = view;
this.overScrollMode = ViewCompat.getOverScrollMode(view);
}
public void setOverScrollMode(int overScrollMode) {
if (overScrollMode < ViewCompat.OVER_SCROLL_ALWAYS || overScrollMode > ViewCompat.OVER_SCROLL_NEVER)
throw new IllegalArgumentException("Unknown overscroll mode: " + overScrollMode);
if (this.view == null) throw new IllegalStateException("view == null");
this.overScrollMode = overScrollMode;
ViewCompat.setOverScrollMode(view, overScrollMode);
}
public static int makeUnspecifiedSpec() {
return View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
}
@Override
public void onMeasure(RecyclerView.Recycler recycler, RecyclerView.State state, int widthSpec, int heightSpec) {
final int widthMode = View.MeasureSpec.getMode(widthSpec);
final int heightMode = View.MeasureSpec.getMode(heightSpec);
final int widthSize = View.MeasureSpec.getSize(widthSpec);
final int heightSize = View.MeasureSpec.getSize(heightSpec);
final boolean hasWidthSize = widthMode != View.MeasureSpec.UNSPECIFIED;
final boolean hasHeightSize = heightMode != View.MeasureSpec.UNSPECIFIED;
final boolean exactWidth = widthMode == View.MeasureSpec.EXACTLY;
final boolean exactHeight = heightMode == View.MeasureSpec.EXACTLY;
final int unspecified = makeUnspecifiedSpec();
if (exactWidth && exactHeight) {
// in case of exact calculations for both dimensions let's use default "onMeasure" implementation
super.onMeasure(recycler, state, widthSpec, heightSpec);
return;
}
final boolean vertical = getOrientation() == VERTICAL;
initChildDimensions(widthSize, heightSize, vertical);
int width = 0;
int height = 0;
// it's possible to get scrap views in recycler which are bound to old (invalid) adapter entities. This
// happens because their invalidation happens after "onMeasure" method. As a workaround let's clear the
// recycler now (it should not cause any performance issues while scrolling as "onMeasure" is never
// called whiles scrolling)
recycler.clear();
final int stateItemCount = state.getItemCount();
final int adapterItemCount = getItemCount();
// adapter always contains actual data while state might contain old data (f.e. data before the animation is
// done). As we want to measure the view with actual data we must use data from the adapter and not from the
// state
for (int i = 0; i < adapterItemCount; i++) {
if (vertical) {
if (!hasChildSize) {
if (i < stateItemCount) {
// we should not exceed state count, otherwise we'll get IndexOutOfBoundsException. For such items
// we will use previously calculated dimensions
measureChild(recycler, i, widthSize, unspecified, childDimensions);
} else {
logMeasureWarning(i);
}
}
height += childDimensions[CHILD_HEIGHT];
if (i == 0) {
width = childDimensions[CHILD_WIDTH];
}
if (hasHeightSize && height >= heightSize) {
break;
}
} else {
if (!hasChildSize) {
if (i < stateItemCount) {
// we should not exceed state count, otherwise we'll get IndexOutOfBoundsException. For such items
// we will use previously calculated dimensions
measureChild(recycler, i, unspecified, heightSize, childDimensions);
} else {
logMeasureWarning(i);
}
}
width += childDimensions[CHILD_WIDTH];
if (i == 0) {
height = childDimensions[CHILD_HEIGHT];
}
if (hasWidthSize && width >= widthSize) {
break;
}
}
}
if (exactWidth) {
width = widthSize;
} else {
width += getPaddingLeft() + getPaddingRight();
if (hasWidthSize) {
width = Math.min(width, widthSize);
}
}
if (exactHeight) {
height = heightSize;
} else {
height += getPaddingTop() + getPaddingBottom();
if (hasHeightSize) {
height = Math.min(height, heightSize);
}
}
setMeasuredDimension(width, height);
if (view != null && overScrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS) {
final boolean fit = (vertical && (!hasHeightSize || height < heightSize))
|| (!vertical && (!hasWidthSize || width < widthSize));
ViewCompat.setOverScrollMode(view, fit ? ViewCompat.OVER_SCROLL_NEVER : ViewCompat.OVER_SCROLL_ALWAYS);
}
}
private void logMeasureWarning(int child) {
if (BuildConfig.DEBUG) {
Log.w("MyLinearLayoutManager", "Can't measure child #" + child + ", previously used dimensions will be reused." +
"To remove this message either use #setChildSize() method or don't run RecyclerView animations");
}
}
private void initChildDimensions(int width, int height, boolean vertical) {
if (childDimensions[CHILD_WIDTH] != 0 || childDimensions[CHILD_HEIGHT] != 0) {
// already initialized, skipping
return;
}
if (vertical) {
childDimensions[CHILD_WIDTH] = width;
childDimensions[CHILD_HEIGHT] = childSize;
} else {
childDimensions[CHILD_WIDTH] = childSize;
childDimensions[CHILD_HEIGHT] = height;
}
}
@Override
public void setOrientation(int orientation) {
// might be called before the constructor of this class is called
//noinspection ConstantConditions
if (childDimensions != null) {
if (getOrientation() != orientation) {
childDimensions[CHILD_WIDTH] = 0;
childDimensions[CHILD_HEIGHT] = 0;
}
}
super.setOrientation(orientation);
}
public void clearChildSize() {
hasChildSize = false;
setChildSize(DEFAULT_CHILD_SIZE);
}
public void setChildSize(int childSize) {
hasChildSize = true;
if (this.childSize != childSize) {
this.childSize = childSize;
requestLayout();
}
}
private void measureChild(RecyclerView.Recycler recycler, int position, int widthSize, int heightSize, int[] dimensions) {
final View child;
try {
child = recycler.getViewForPosition(position);
} catch (IndexOutOfBoundsException e) {
if (BuildConfig.DEBUG) {
Log.w("MyLinearLayoutManager", "MyLinearLayoutManager doesn't work well with animations. Consider switching them off", e);
}
return;
}
final RecyclerView.LayoutParams p = (RecyclerView.LayoutParams) child.getLayoutParams();
final int hPadding = getPaddingLeft() + getPaddingRight();
final int vPadding = getPaddingTop() + getPaddingBottom();
final int hMargin = p.leftMargin + p.rightMargin;
final int vMargin = p.topMargin + p.bottomMargin;
// we must make insets dirty in order calculateItemDecorationsForChild to work
makeInsetsDirty(p);
// this method should be called before any getXxxDecorationXxx() methods
calculateItemDecorationsForChild(child, tmpRect);
final int hDecoration = getRightDecorationWidth(child) + getLeftDecorationWidth(child);
final int vDecoration = getTopDecorationHeight(child) + getBottomDecorationHeight(child);
final int childWidthSpec = getChildMeasureSpec(widthSize, hPadding + hMargin + hDecoration, p.width, canScrollHorizontally());
final int childHeightSpec = getChildMeasureSpec(heightSize, vPadding + vMargin + vDecoration, p.height, canScrollVertically());
child.measure(childWidthSpec, childHeightSpec);
dimensions[CHILD_WIDTH] = getDecoratedMeasuredWidth(child) + p.leftMargin + p.rightMargin;
dimensions[CHILD_HEIGHT] = getDecoratedMeasuredHeight(child) + p.bottomMargin + p.topMargin;
// as view is recycled let's not keep old measured values
makeInsetsDirty(p);
recycler.recycleView(child);
}
private static void makeInsetsDirty(RecyclerView.LayoutParams p) {
if (!canMakeInsetsDirty) {
return;
}
try {
if (insetsDirtyField == null) {
insetsDirtyField = RecyclerView.LayoutParams.class.getDeclaredField("mInsetsDirty");
insetsDirtyField.setAccessible(true);
}
insetsDirtyField.set(p, true);
} catch (NoSuchFieldException e) {
onMakeInsertDirtyFailed();
} catch (IllegalAccessException e) {
onMakeInsertDirtyFailed();
}
}
private static void onMakeInsertDirtyFailed() {
canMakeInsetsDirty = false;
if (BuildConfig.DEBUG) {
Log.w("MyLinearLayoutManager", "Can't make LayoutParams insets dirty, decorations measurements might be incorrect");
}
}
}
尝试这个。很晚的答案。但肯定会在未来帮助任何人。
将您的 Scrollview 设置为 NestedScrollView
<android.support.v4.widget.NestedScrollView>
<android.support.v7.widget.RecyclerView>
</android.support.v7.widget.RecyclerView>
</android.support.v4.widget.NestedScrollView>
在您的回收站视图中
recyclerView.setNestedScrollingEnabled(false);
recyclerView.setHasFixedSize(false);
如果您将 RecyclerView
放入 NestedScrollView
并启用 recyclerView.setNestedScrollingEnabled(false);
,滚动将正常工作。
但是,有一个问题
RecyclerView 不回收
例如,您的 RecyclerView
(在 NestedScrollView
或 ScrollView
内)有 100 个项目。
当 Activity
启动时,100 个项目将创建(onCreateViewHolder
和 onBindViewHolder
100 个项目将同时调用)。
例如,对于每个项目,您将从 API => 加载一个大图像活动创建->将加载 100 张图片。
它使启动 Activity 缓慢和滞后。
可能的解决方案:
- 考虑将 RecyclerView
与多种类型一起使用。
但是,如果在您的情况下,RecyclerView
中只有几个项目,并且 recycle 或 don't recycle 不会对性能产生很大影响,您可以使用 { 1} 在 ScrollView
内简单
RecyclerView
在放到 ScrollView
后回收。如果你想回收,考虑另一种方法(比如使用多种类型的 RecyclerView)
更新:这个答案现在已经过时了,因为有像 NestedScrollView 和 RecyclerView 这样的小部件支持嵌套滚动。
您永远不应该将可滚动视图放在另一个可滚动视图中!
我建议你制作你的主要布局回收视图并将你的视图作为回收视图的项目。
看看这个例子,它展示了如何在回收器视图适配器中使用多个视图。 link to example
NestedScrollView
似乎确实解决了这个问题。我已经使用这种布局进行了测试:
<android.support.v4.widget.NestedScrollView
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"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/dummy_text"
/>
<android.support.v7.widget.CardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
>
<android.support.v7.widget.RecyclerView
android:id="@+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</android.support.v7.widget.CardView>
</LinearLayout>
它可以正常工作
您可以使用这种方式:
将此行添加到您的 recyclerView xml 视图中:
android:nestedScrollingEnabled="false"
试试看,recyclerview 会以灵活的高度平滑滚动
希望这有帮助。
我使用 CustomLayoutManager 来禁用 RecyclerView 滚动。也不要将 Recycler View 用作 WrapContent,将其用作 0dp,Weight=1
public class CustomLayoutManager extends LinearLayoutManager {
private boolean isScrollEnabled;
// orientation should be LinearLayoutManager.VERTICAL or HORIZONTAL
public CustomLayoutManager(Context context, int orientation, boolean isScrollEnabled) {
super(context, orientation, false);
this.isScrollEnabled = isScrollEnabled;
}
@Override
public boolean canScrollVertically() {
//Similarly you can customize "canScrollHorizontally()" for managing horizontal scroll
return isScrollEnabled && super.canScrollVertically();
}
}
在 RecyclerView 中使用 CustomLayoutManager:
CustomLayoutManager mLayoutManager = new CustomLayoutManager(getBaseActivity(), CustomLayoutManager.VERTICAL, false);
recyclerView.setLayoutManager(mLayoutManager);
((DefaultItemAnimator) recyclerView.getItemAnimator()).setSupportsChangeAnimations(false);
recyclerView.setAdapter(statsAdapter);
用户界面 XML:
<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/background_main"
android:fillViewport="false">
<LinearLayout
android:id="@+id/contParentLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<edu.aku.family_hifazat.libraries.mpchart.charts.PieChart
android:id="@+id/chart1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="@dimen/x20dp"
android:minHeight="@dimen/x300dp">
</edu.aku.family_hifazat.libraries.mpchart.charts.PieChart>
</FrameLayout>
<android.support.v7.widget.RecyclerView
android:id="@+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1">
</android.support.v7.widget.RecyclerView>
</LinearLayout>
</ScrollView>
我遇到了同样的问题。这就是我尝试过的并且有效。我正在分享我的 xml 和 java 代码。希望这会对某人有所帮助。
这是xml
<?xml version="1.0" encoding="utf-8"?>
< NestedScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<ImageView
android:id="@+id/iv_thumbnail"
android:layout_width="match_parent"
android:layout_height="200dp" />
<TextView
android:id="@+id/tv_description"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Description" />
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Buy" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Reviews" />
<android.support.v7.widget.RecyclerView
android:id="@+id/rc_reviews"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</android.support.v7.widget.RecyclerView>
</LinearLayout>
</NestedScrollView >
这是相关的java代码。它就像一个魅力。
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
linearLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
recyclerView.setLayoutManager(linearLayoutManager);
recyclerView.setNestedScrollingEnabled(false);
NestedScrollView
而不是滚动视图
实际上RecyclerView
的主要目的是补偿ListView
和ScrollView
。而不是做你实际在做的事情:在 ScrollView
中有一个 RecyclerView
,我建议只有一个 RecyclerView
可以处理多种类型的孩子。
这可以解决问题:
recyclerView.setNestedScrollingEnabled(false);
首先,您应该使用 NestedScrollView
而不是 ScrollView
并将 RecyclerView
放在 NestedScrollView
中。
使用自定义布局类来测量屏幕的高度和宽度:
public class CustomLinearLayoutManager extends LinearLayoutManager {
public CustomLinearLayoutManager(Context context, int orientation, boolean reverseLayout) {
super(context, orientation, reverseLayout);
}
private int[] mMeasuredDimension = new int[2];
@Override
public void onMeasure(RecyclerView.Recycler recycler, RecyclerView.State state,
int widthSpec, int heightSpec) {
final int widthMode = View.MeasureSpec.getMode(widthSpec);
final int heightMode = View.MeasureSpec.getMode(heightSpec);
final int widthSize = View.MeasureSpec.getSize(widthSpec);
final int heightSize = View.MeasureSpec.getSize(heightSpec);
int width = 0;
int height = 0;
for (int i = 0; i < getItemCount(); i++) {
if (getOrientation() == HORIZONTAL) {
measureScrapChild(recycler, i,
View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
heightSpec,
mMeasuredDimension);
width = width + mMeasuredDimension[0];
if (i == 0) {
height = mMeasuredDimension[1];
}
} else {
measureScrapChild(recycler, i,
widthSpec,
View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
mMeasuredDimension);
height = height + mMeasuredDimension[1];
if (i == 0) {
width = mMeasuredDimension[0];
}
}
}
switch (widthMode) {
case View.MeasureSpec.EXACTLY:
width = widthSize;
case View.MeasureSpec.AT_MOST:
case View.MeasureSpec.UNSPECIFIED:
}
switch (heightMode) {
case View.MeasureSpec.EXACTLY:
height = heightSize;
case View.MeasureSpec.AT_MOST:
case View.MeasureSpec.UNSPECIFIED:
}
setMeasuredDimension(width, height);
}
private void measureScrapChild(RecyclerView.Recycler recycler, int position, int widthSpec,
int heightSpec, int[] measuredDimension) {
View view = recycler.getViewForPosition(position);
recycler.bindViewToPosition(view, position);
if (view != null) {
RecyclerView.LayoutParams p = (RecyclerView.LayoutParams) view.getLayoutParams();
int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec,
getPaddingLeft() + getPaddingRight(), p.width);
int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec,
getPaddingTop() + getPaddingBottom(), p.height);
view.measure(childWidthSpec, childHeightSpec);
measuredDimension[0] = view.getMeasuredWidth() + p.leftMargin + p.rightMargin;
measuredDimension[1] = view.getMeasuredHeight() + p.bottomMargin + p.topMargin;
recycler.recycleView(view);
}
}
}
并在 RecyclerView
的活动/片段中实现以下代码:
final CustomLinearLayoutManager layoutManager = new CustomLinearLayoutManager(this, LinearLayoutManager.VERTICAL, false);
recyclerView.setLayoutManager(layoutManager);
recyclerView.setAdapter(mAdapter);
recyclerView.setNestedScrollingEnabled(false); // Disables scrolling for RecyclerView, CustomLinearLayoutManager used instead of MyLinearLayoutManager
recyclerView.setHasFixedSize(false);
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
int visibleItemCount = layoutManager.getChildCount();
int totalItemCount = layoutManager.getItemCount();
int lastVisibleItemPos = layoutManager.findLastVisibleItemPosition();
Log.i("getChildCount", String.valueOf(visibleItemCount));
Log.i("getItemCount", String.valueOf(totalItemCount));
Log.i("lastVisibleItemPos", String.valueOf(lastVisibleItemPos));
if ((visibleItemCount + lastVisibleItemPos) >= totalItemCount) {
Log.i("LOG", "Last Item Reached!");
}
}
});
如果 RecyclerView 在 ScrollView 中只显示一行。您只需要将行的高度设置为 android:layout_height="wrap_content"
。
您还可以覆盖 LinearLayoutManager 以使 recyclerview 顺利滚动
@Override
public boolean canScrollVertically(){
return false;
}
很抱歉迟到了,但似乎还有另一种解决方案非常适合您提到的情况。
如果您在回收站视图中使用回收站视图,它似乎工作得非常好。我亲自尝试并使用过它,它似乎一点也不慢,也不生涩。现在我不确定这是否是一个好习惯,但是嵌套多个回收器视图,甚至嵌套的滚动视图都会变慢。但这似乎工作得很好。请试一试。我相信嵌套会很好。
解决此问题的另一种方法是在 ScrollView
中使用 ConstraintLayout
:
<ScrollView>
<ConstraintLayout> (this is the only child of ScrollView)
<...Some Views...>
<RecyclerView> (layout_height=wrap_content)
<...Some Other Views...>
但我仍然会坚持 androidx.core.widget.NestedScrollView
approach, proposed by Yang Peiyong。
您可以尝试将回收站视图 Hight 设置为 wrap_content。就我而言,它工作正常。我正在滚动视图中尝试使用 2 个不同的回收器视图
最好的解决方案是将 multiple Views
保留在 Single View / View Group
中,然后将那个视图保留在 SrcollView 中。 即。
格式 -
<ScrollView>
<Another View>
<RecyclerView>
<TextView>
<And Other Views>
</Another View>
</ScrollView>
例如。
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:text="any text"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
<TextView
android:text="any text"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</ScrollView>
另一个例如。具有多个视图的 ScrollView
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:orientation="vertical"
android:layout_weight="1">
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/imageView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#FFFFFF"
/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingHorizontal="10dp"
android:orientation="vertical">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/CategoryItem"
android:textSize="20sp"
android:textColor="#000000"
/>
<TextView
android:textColor="#000000"
android:text="₹1000"
android:textSize="18sp"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
<TextView
android:textColor="#000000"
android:text="so\nugh\nos\nghs\nrgh\n
sghs\noug\nhro\nghreo\nhgor\ngheroh\ngr\neoh\n
og\nhrf\ndhog\n
so\nugh\nos\nghs\nrgh\nsghs\noug\nhro\n
ghreo\nhgor\ngheroh\ngr\neoh\nog\nhrf\ndhog"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
</LinearLayout>
</ScrollView>
对于那些试图仅出于设计目的的人 - 离开它。重新设计您的应用程序,只留下 RecyclerView
。这将是比执行 ANY 硬编码更好的解决方案。
**对我有用的解决方案使用高度为 wrap_content 的 NestedScrollView
<br> RecyclerView
android:layout_width="match_parent"<br>
android:layout_height="wrap_content"<br>
android:nestedScrollingEnabled="false"<br>
app:layoutManager="android.support.v7.widget.LinearLayoutManager"
tools:targetApi="lollipop"<br><br> and view holder layout
<br> android:layout_width="match_parent"<br>
android:layout_height="wrap_content"
//你的行内容放在这里
不定期副业成功案例分享
android:layout_height="wrap_content"
NestedScrollView
对我来说滞后,与ScrollView
不同。不使用NestedScrollView
搜索解决方案