I have a SwipeRefreshLayout around a ViewPager. The fragments loaded by the ViewPager contain ScrollViews. When I scroll down it works fine, but when I scroll up, the SwipeRefreshLayout activates without letting the ScrollView scroll up first. How can I make sure the ScrollView has priority?
It worked fine when the SwipeRefreshLayout was in the individual fragments just outside the ScrollView, but I need it to be on the activity itself around the ViewPager.
Here are the relevant layouts:
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>
Fragment loaded by the ViewPager (there are 5 tabs, each with one of these):
<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>
And HERE is the repo on GitHub in case you need more information:
Google resolve this issue with an example posted on the google-sample github projet.
Create a view that extends the original SwipeRefreshLayout :
/*
* 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)
}
Use this view in your xml layout :
<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>
And in your activity or fragment, you can use this component with :
mSwipeRefreshLayout = (MultiSwipeRefreshLayout) view.findViewById(R.id.swiperefresh);
mSwipeRefreshLayout.setSwipeableChildren(android.R.id.list, android.R.id.empty);
android.R.id.list and android.R.id.empty is the ids for your list or recycler view. The view work perfectly with two list with same ids.
You can see real example at the google-sample github project.
Replace your ScrollView with a NestedScrollView the scrolling behavior will work as you expect it to.
I solved the problem. I created SwipeRefreshLayout like this:
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()
}
}
and I set the target to the visible ScrollView every time the ViewPager changes views.
BTW that's Kotlin, not Java.
