Google通過在google-sample github projet上發佈的示例解決了這個問題。
創建擴展原有SwipeRefreshLayout一個觀點:
/*
* 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)
}
使用此觀點在你的XML佈局:
<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>
而在你的活動或片段,您可以使用該組件具有:
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是您的列表的ID或回收者視圖。該視圖與兩個具有相同ID的列表完美結合。
你可以在google-sample github project看到真實的例子。
是的,但我怎麼知道什麼位置的ListView第一個元素? –
getFirstvisiablePosition()== 0表示listview處於初始位置。 – starkshang
thx FireSun不錯)) –