SwipeRefreshLayout 干扰 ViewPager 中的 ScrollView
SwipeRefreshLayout interferes with ScrollView in a ViewPager
我在 ViewPager 周围有一个 SwipeRefreshLayout。 ViewPager 加载的片段包含ScrollViews。当我向下滚动时它工作正常，但是当我向上滚动时，SwipeRefreshLayout 激活而不让 ScrollView 先向上滚动。如何确保 ScrollView 具有优先权？
当 SwipeRefreshLayout 位于 ScrollView 外部的各个片段中时它工作正常，但我需要它位于 ViewPager 周围的 activity 本身。
以下是相关布局：
Activity:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="#EEEEEE"
android:fitsSystemWindows="true">
<include layout="@layout/toolbar" />
<io.karim.MaterialTabs
android:id="@+id/tabs"
android:layout_width="match_parent"
android:layout_height="48dp"
android:background="@color/primary"
app:mtIndicatorColor="@color/icons"
app:mtIndicatorHeight="2dp"
app:mtSameWeightTabs="true"
app:mtPaddingMiddle="false"
app:mtTextColorSelected="@color/icons"
android:textColor="@color/icons"
android:elevation="4dp"
tools:ignore="UnusedAttribute" />
<android.support.v4.widget.SwipeRefreshLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/swipeRefresh"
android:layout_height="wrap_content"
android:layout_width="match_parent">
<android.support.v4.view.ViewPager
android:id="@+id/pager"
android:layout_width="match_parent"
android:layout_height="0dp" />
</android.support.v4.widget.SwipeRefreshLayout>
</LinearLayout>
ViewPager 加载的片段（有 5 个选项卡，每个选项卡都有其中之一）：
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="me.sargunvohra.android.purduediningcourts.presenter.MenuFragment">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingStart="@dimen/activity_horizontal_margin"
android:paddingEnd="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
>
<!-- Content snipped for brevity -->
<!-- blah blah... lots of content here -->
</LinearLayout>
</ScrollView>
HERE 是 GitHub 上的回购协议，如果您需要更多信息：
我解决了这个问题。我这样创建了 SwipeRefreshLayout：
public class MenuSwipeRefreshLayout: SwipeRefreshLayout {
public var target: View? = null
constructor(ctx: Context): super(ctx)
constructor(ctx: Context, attr: AttributeSet): super(ctx, attr)
override fun canChildScrollUp(): Boolean {
return target?.canScrollVertically(-1) ?: super.canChildScrollUp()
}
}
每次 ViewPager 更改视图时，我都将目标设置为可见的 ScrollView。
顺便说一句，那是 Kotlin，而不是 Java。
Google 使用 google-示例 github 项目上发布的示例解决此问题。
创建一个扩展原始 SwipeRefreshLayout 的视图：
/*
* Copyright 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.swiperefreshmultipleviews;
import android.content.Context;
import android.support.v4.view.ViewCompat;
import android.support.v4.widget.SwipeRefreshLayout;
import android.util.AttributeSet;
import android.view.View;
import android.widget.AbsListView;
/**
* A descendant of {@link android.support.v4.widget.SwipeRefreshLayout} which supports multiple
* child views triggering a refresh gesture. You set the views which can trigger the gesture via
* {@link #setSwipeableChildren(int...)}, providing it the child ids.
*/
public class MultiSwipeRefreshLayout extends SwipeRefreshLayout {
private View[] mSwipeableChildren;
public MultiSwipeRefreshLayout(Context context) {
super(context);
}
public MultiSwipeRefreshLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
/**
* Set the children which can trigger a refresh by swiping down when they are visible. These
* views need to be a descendant of this view.
*/
public void setSwipeableChildren(final int... ids) {
assert ids != null;
// Iterate through the ids and find the Views
mSwipeableChildren = new View[ids.length];
for (int i = 0; i < ids.length; i++) {
mSwipeableChildren[i] = findViewById(ids[i]);
}
}
// BEGIN_INCLUDE(can_child_scroll_up)
/**
* This method controls when the swipe-to-refresh gesture is triggered. By returning false here
* we are signifying that the view is in a state where a refresh gesture can start.
*
* <p>As {@link android.support.v4.widget.SwipeRefreshLayout} only supports one direct child by
* default, we need to manually iterate through our swipeable children to see if any are in a
* state to trigger the gesture. If so we return false to start the gesture.
*/
@Override
public boolean canChildScrollUp() {
if (mSwipeableChildren != null && mSwipeableChildren.length > 0) {
// Iterate through the scrollable children and check if any of them can not scroll up
for (View view : mSwipeableChildren) {
if (view != null && view.isShown() && !canViewScrollUp(view)) {
// If the view is shown, and can not scroll upwards, return false and start the
// gesture.
return false;
}
}
}
return true;
}
// END_INCLUDE(can_child_scroll_up)
// BEGIN_INCLUDE(can_view_scroll_up)
/**
* Utility method to check whether a {@link View} can scroll up from it's current position.
* Handles platform version differences, providing backwards compatible functionality where
* needed.
*/
private static boolean canViewScrollUp(View view) {
if (android.os.Build.VERSION.SDK_INT >= 14) {
// For ICS and above we can call canScrollVertically() to determine this
return ViewCompat.canScrollVertically(view, -1);
} else {
if (view instanceof AbsListView) {
// Pre-ICS we need to manually check the first visible item and the child view's top
// value
final AbsListView listView = (AbsListView) view;
return listView.getChildCount() > 0 &&
(listView.getFirstVisiblePosition() > 0
|| listView.getChildAt(0).getTop() < listView.getPaddingTop());
} else {
// For all other view types we just check the getScrollY() value
return view.getScrollY() > 0;
}
}
}
// END_INCLUDE(can_view_scroll_up)
}
在您的 xml 布局中使用此视图：
<com.example.android.swiperefreshmultipleviews.MultiSwipeRefreshLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/swiperefresh"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- your code -->
</com.example.android.swiperefreshmultipleviews.MultiSwipeRefreshLayout>
并且在您的 activity 或片段中，您可以将此组件与 :
一起使用
mSwipeRefreshLayout = (MultiSwipeRefreshLayout) view.findViewById(R.id.swiperefresh);
mSwipeRefreshLayout.setSwipeableChildren(android.R.id.list, android.R.id.empty);
android.R.id.list 和 android.R.id.empty 是您的列表或回收站视图的 ID。该视图与具有相同 ID 的两个列表完美配合。
你可以在 google-sample github project 看到真实的例子。
替换您的 ScrollView with a NestedScrollView 滚动行为将如您所愿。
我在 ViewPager 周围有一个 SwipeRefreshLayout。 ViewPager 加载的片段包含ScrollViews。当我向下滚动时它工作正常，但是当我向上滚动时，SwipeRefreshLayout 激活而不让 ScrollView 先向上滚动。如何确保 ScrollView 具有优先权？
当 SwipeRefreshLayout 位于 ScrollView 外部的各个片段中时它工作正常，但我需要它位于 ViewPager 周围的 activity 本身。
以下是相关布局：
Activity:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="#EEEEEE"
android:fitsSystemWindows="true">
<include layout="@layout/toolbar" />
<io.karim.MaterialTabs
android:id="@+id/tabs"
android:layout_width="match_parent"
android:layout_height="48dp"
android:background="@color/primary"
app:mtIndicatorColor="@color/icons"
app:mtIndicatorHeight="2dp"
app:mtSameWeightTabs="true"
app:mtPaddingMiddle="false"
app:mtTextColorSelected="@color/icons"
android:textColor="@color/icons"
android:elevation="4dp"
tools:ignore="UnusedAttribute" />
<android.support.v4.widget.SwipeRefreshLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/swipeRefresh"
android:layout_height="wrap_content"
android:layout_width="match_parent">
<android.support.v4.view.ViewPager
android:id="@+id/pager"
android:layout_width="match_parent"
android:layout_height="0dp" />
</android.support.v4.widget.SwipeRefreshLayout>
</LinearLayout>
ViewPager 加载的片段（有 5 个选项卡，每个选项卡都有其中之一）：
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="me.sargunvohra.android.purduediningcourts.presenter.MenuFragment">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingStart="@dimen/activity_horizontal_margin"
android:paddingEnd="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
>
<!-- Content snipped for brevity -->
<!-- blah blah... lots of content here -->
</LinearLayout>
</ScrollView>
HERE 是 GitHub 上的回购协议，如果您需要更多信息：
我解决了这个问题。我这样创建了 SwipeRefreshLayout：
public class MenuSwipeRefreshLayout: SwipeRefreshLayout {
public var target: View? = null
constructor(ctx: Context): super(ctx)
constructor(ctx: Context, attr: AttributeSet): super(ctx, attr)
override fun canChildScrollUp(): Boolean {
return target?.canScrollVertically(-1) ?: super.canChildScrollUp()
}
}
每次 ViewPager 更改视图时，我都将目标设置为可见的 ScrollView。
顺便说一句，那是 Kotlin，而不是 Java。
Google 使用 google-示例 github 项目上发布的示例解决此问题。
创建一个扩展原始 SwipeRefreshLayout 的视图：
/*
* Copyright 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.swiperefreshmultipleviews;
import android.content.Context;
import android.support.v4.view.ViewCompat;
import android.support.v4.widget.SwipeRefreshLayout;
import android.util.AttributeSet;
import android.view.View;
import android.widget.AbsListView;
/**
* A descendant of {@link android.support.v4.widget.SwipeRefreshLayout} which supports multiple
* child views triggering a refresh gesture. You set the views which can trigger the gesture via
* {@link #setSwipeableChildren(int...)}, providing it the child ids.
*/
public class MultiSwipeRefreshLayout extends SwipeRefreshLayout {
private View[] mSwipeableChildren;
public MultiSwipeRefreshLayout(Context context) {
super(context);
}
public MultiSwipeRefreshLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
/**
* Set the children which can trigger a refresh by swiping down when they are visible. These
* views need to be a descendant of this view.
*/
public void setSwipeableChildren(final int... ids) {
assert ids != null;
// Iterate through the ids and find the Views
mSwipeableChildren = new View[ids.length];
for (int i = 0; i < ids.length; i++) {
mSwipeableChildren[i] = findViewById(ids[i]);
}
}
// BEGIN_INCLUDE(can_child_scroll_up)
/**
* This method controls when the swipe-to-refresh gesture is triggered. By returning false here
* we are signifying that the view is in a state where a refresh gesture can start.
*
* <p>As {@link android.support.v4.widget.SwipeRefreshLayout} only supports one direct child by
* default, we need to manually iterate through our swipeable children to see if any are in a
* state to trigger the gesture. If so we return false to start the gesture.
*/
@Override
public boolean canChildScrollUp() {
if (mSwipeableChildren != null && mSwipeableChildren.length > 0) {
// Iterate through the scrollable children and check if any of them can not scroll up
for (View view : mSwipeableChildren) {
if (view != null && view.isShown() && !canViewScrollUp(view)) {
// If the view is shown, and can not scroll upwards, return false and start the
// gesture.
return false;
}
}
}
return true;
}
// END_INCLUDE(can_child_scroll_up)
// BEGIN_INCLUDE(can_view_scroll_up)
/**
* Utility method to check whether a {@link View} can scroll up from it's current position.
* Handles platform version differences, providing backwards compatible functionality where
* needed.
*/
private static boolean canViewScrollUp(View view) {
if (android.os.Build.VERSION.SDK_INT >= 14) {
// For ICS and above we can call canScrollVertically() to determine this
return ViewCompat.canScrollVertically(view, -1);
} else {
if (view instanceof AbsListView) {
// Pre-ICS we need to manually check the first visible item and the child view's top
// value
final AbsListView listView = (AbsListView) view;
return listView.getChildCount() > 0 &&
(listView.getFirstVisiblePosition() > 0
|| listView.getChildAt(0).getTop() < listView.getPaddingTop());
} else {
// For all other view types we just check the getScrollY() value
return view.getScrollY() > 0;
}
}
}
// END_INCLUDE(can_view_scroll_up)
}
在您的 xml 布局中使用此视图：
<com.example.android.swiperefreshmultipleviews.MultiSwipeRefreshLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/swiperefresh"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- your code -->
</com.example.android.swiperefreshmultipleviews.MultiSwipeRefreshLayout>
并且在您的 activity 或片段中，您可以将此组件与 :
一起使用mSwipeRefreshLayout = (MultiSwipeRefreshLayout) view.findViewById(R.id.swiperefresh);
mSwipeRefreshLayout.setSwipeableChildren(android.R.id.list, android.R.id.empty);
android.R.id.list 和 android.R.id.empty 是您的列表或回收站视图的 ID。该视图与具有相同 ID 的两个列表完美配合。
你可以在 google-sample github project 看到真实的例子。
替换您的 ScrollView with a NestedScrollView 滚动行为将如您所愿。