RefreshLayout + CoordinatorLayout + AppBarLayout + MagicIndicator + ViewPager + Fragment
这是一个老生常谈的问题,网上也有很多优秀的方案,我也是经过自己的搜索、对比,最终选择出现在使用的这套
这个问题的主要点有三个
1:AppBarLayout 必须要设置layout_behavior
2:折叠部分必须要设置layout_scrollFlags
3:位于悬浮部分下面的viewpager必须设置layout_behavior
xml的布局文件:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
android:id="@+id/main_content"
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:background="@color/white"
android:focusable="true"
android:focusableInTouchMode="true"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!--页面顶部部分,比如返回按钮、标题等-->
<RelativeLayout
android:layout_marginTop="@dimen/dp_25"
android:id="@+id/rl_top_nav"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
android:layout_width="match_parent"
android:layout_height="@dimen/dp_44">
</RelativeLayout>
<com.scwang.smartrefresh.layout.SmartRefreshLayout
android:layout_marginTop="@dimen/dp_70"
android:id="@+id/refresh_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:srlEnableLoadMore="false"
app:srlHeaderTriggerRate="0.8"
app:srlEnableRefresh="true">
<com.kongfz.app.core.ui.widget.loading.RefreshHeaderView2
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<com.kongfz.app.core.kfz2.widgets.MyCoordinatorLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<com.google.android.material.appbar.AppBarLayout
android:id="@+id/appbarlayout"
app:elevation="0dp"
app:layout_behavior="com.kongfz.app.core.kfz2.widgets.appbar.FixAppBarLayoutBehavior"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<!--折叠部分-->
<androidx.recyclerview.widget.RecyclerView
app:layout_scrollFlags="scroll|enterAlwaysCollapsed"
android:id="@+id/rv_top"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<!--悬浮部分-->
<RelativeLayout
android:id="@+id/rl_tab"
android:paddingHorizontal="@dimen/dp_30"
android:background="@drawable/home_total_list_bg"
android:layout_width="match_parent"
android:layout_height="@dimen/dp_50">
<RelativeLayout
android:layout_centerInParent="true"
android:layout_width="wrap_content"
android:layout_height="@dimen/dp_50">
<com.kongfz.app.core.common.widgets.tab.MagicIndicator
android:layout_marginTop="@dimen/dp_1"
android:id="@+id/magicIndicator_recommend"
android:layout_width="@dimen/dp_300"
android:layout_height="@dimen/dp_49" />
</RelativeLayout>
</RelativeLayout>
</com.google.android.material.appbar.AppBarLayout>
<androidx.viewpager.widget.ViewPager
android:background="@color/gray4"
android:id="@+id/vp_recommend"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior" />
</com.kongfz.app.core.kfz2.widgets.MyCoordinatorLayout>
</com.scwang.smartrefresh.layout.SmartRefreshLayout>
<!--暂无数据的空页面-->
<RelativeLayout
android:layout_below="@id/rl_top_nav"
android:visibility="gone"
android:id="@+id/rl_empty"
android:background="@color/white"
android:layout_width="match_parent"
android:layout_height="match_parent">
</RelativeLayout>
<!--用来展示骨架屏-->
<RelativeLayout
android:id="@+id/rl_ske"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@id/rl_top_nav" />
</RelativeLayout>
AppBarLayout的Behavior:
import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.widget.OverScroller;
import androidx.coordinatorlayout.widget.CoordinatorLayout;
import com.google.android.material.appbar.AppBarLayout;
import java.lang.reflect.Field;
//用于解决CoordinatorLayout+AppBarLayout+RecyclerView导致的滑动冲突抖动
public class FixAppBarLayoutBehavior extends AppBarLayout.Behavior{
private static final String TAG = "FixBehavior";
private static final int TYPE_FLING = 1;
private boolean isFlinging;
private boolean shouldBlockNestedScroll;
public FixAppBarLayoutBehavior(Context context, AttributeSet attrs) {
super(context, attrs);
}
@Override
public boolean onInterceptTouchEvent(CoordinatorLayout parent, AppBarLayout child, MotionEvent ev) {
Log.d(TAG, "onInterceptTouchEvent:" + child.getTotalScrollRange());
shouldBlockNestedScroll = isFlinging;
switch (ev.getActionMasked()) {
case MotionEvent.ACTION_DOWN:
//手指触摸屏幕的时候停止fling事件
stopAppbarLayoutFling(child);
break;
default:
break;
}
return super.onInterceptTouchEvent(parent, child, ev);
}
/**
* 反射获取私有的flingRunnable 属性,考虑support 28以后变量名修改的问题
*
* @return Field
*/
private Field getFlingRunnableField() throws NoSuchFieldException {
Class<?> superclass = this.getClass().getSuperclass();
try {
// support design 27及一下版本
Class<?> headerBehaviorType = null;
if (superclass != null) {
headerBehaviorType = superclass.getSuperclass();
}
if (headerBehaviorType != null) {
return headerBehaviorType.getDeclaredField("mFlingRunnable");
} else {
return null;
}
} catch (NoSuchFieldException e) {
e.printStackTrace();
// 可能是28及以上版本
Class<?> headerBehaviorType = superclass.getSuperclass().getSuperclass();
if (headerBehaviorType != null) {
return headerBehaviorType.getDeclaredField("flingRunnable");
} else {
return null;
}
}
}
/**
* 反射获取私有的scroller 属性,考虑support 28以后变量名修改的问题
*
* @return Field
*/
private Field getScrollerField() throws NoSuchFieldException {
Class<?> superclass = this.getClass().getSuperclass();
try {
// support design 27及一下版本
Class<?> headerBehaviorType = null;
if (superclass != null) {
headerBehaviorType = superclass.getSuperclass();
}
if (headerBehaviorType != null) {
return headerBehaviorType.getDeclaredField("mScroller");
} else {
return null;
}
} catch (NoSuchFieldException e) {
e.printStackTrace();
// 可能是28及以上版本
Class<?> headerBehaviorType = superclass.getSuperclass().getSuperclass();
if (headerBehaviorType != null) {
return headerBehaviorType.getDeclaredField("scroller");
} else {
return null;
}
}
}
/**
* 停止appbarLayout的fling事件
*
* @param appBarLayout
*/
private void stopAppbarLayoutFling(AppBarLayout appBarLayout) {
//通过反射拿到HeaderBehavior中的flingRunnable变量
try {
Field flingRunnableField = getFlingRunnableField();
Runnable flingRunnable;
if (flingRunnableField != null) {
flingRunnableField.setAccessible(true);
flingRunnable = (Runnable) flingRunnableField.get(this);
if (flingRunnable != null) {
Log.d(TAG, "存在flingRunnable");
appBarLayout.removeCallbacks(flingRunnable);
flingRunnableField.set(this, null);
}
}
Field scrollerField = getScrollerField();
if (scrollerField != null) {
scrollerField.setAccessible(true);
OverScroller overScroller = (OverScroller) scrollerField.get(this);
if (overScroller != null && !overScroller.isFinished()) {
overScroller.abortAnimation();
}
}
} catch (NoSuchFieldException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
}
}
@Override
public boolean onStartNestedScroll(CoordinatorLayout parent, AppBarLayout child, View directTargetChild, View target, int nestedScrollAxes, int type) {
Log.d(TAG, "onStartNestedScroll");
stopAppbarLayoutFling(child);
return super.onStartNestedScroll(parent, child, directTargetChild, target,
nestedScrollAxes, type);
}
@Override
public void onNestedPreScroll(CoordinatorLayout coordinatorLayout, AppBarLayout child, View target, int dx, int dy, int[] consumed, int type) {
Log.d(TAG, "onNestedPreScroll:" + child.getTotalScrollRange() + " ,dx:" + dx + " ,dy:" + dy + " ,type:" + type);
//type返回1时,表示当前target处于非touch的滑动,
//该bug的引起是因为appbar在滑动时,CoordinatorLayout内的实现NestedScrollingChild2接口的滑动
//子类还未结束其自身的fling
//所以这里监听子类的非touch时的滑动,然后block掉滑动事件传递给AppBarLayout
if (type == TYPE_FLING) {
isFlinging = true;
}
if (!shouldBlockNestedScroll) {
super.onNestedPreScroll(coordinatorLayout, child, target, dx, dy, consumed, type);
}
}
@Override
public void onNestedScroll(CoordinatorLayout coordinatorLayout, AppBarLayout child, View target, int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed, int type) {
Log.d(TAG, "onNestedScroll: target:" + target.getClass() + " ," + child.getTotalScrollRange() + " ,dxConsumed:" + dxConsumed + " ,dyConsumed:" + dyConsumed + " " + ",type:" + type);
if (!shouldBlockNestedScroll) {
super.onNestedScroll(coordinatorLayout, child, target, dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed, type);
}
}
@Override
public void onStopNestedScroll(CoordinatorLayout coordinatorLayout, AppBarLayout abl, View target, int type) {
Log.d(TAG, "onStopNestedScroll");
super.onStopNestedScroll(coordinatorLayout, abl, target, type);
isFlinging = false;
shouldBlockNestedScroll = false;
}
}
兼容横向滑动的MyCoordinatorLayout:
import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.coordinatorlayout.widget.CoordinatorLayout;
import androidx.core.view.ViewCompat;
public class MyCoordinatorLayout extends CoordinatorLayout {
public MyCoordinatorLayout(@NonNull Context context) {
super(context);
}
public MyCoordinatorLayout(@NonNull Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
}
public MyCoordinatorLayout(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
@Override
public boolean onStartNestedScroll(View child, View target, int axes, int type) {
if ((axes & ViewCompat.SCROLL_AXIS_HORIZONTAL) != 0) {
//不处理横向嵌套滑动事件
return false;
}
return super.onStartNestedScroll(child, target, axes, type);
}
}
Fragment中的xml,注意这里最外层的layout_behavio设置,这里可以看到空页面时我使用了NestedScrollView,并且设置了app:layout_behavior,主要是我们需要空页面的时候也能跟随顶部折叠部分收起而滑动;这里的骨架屏也是同理
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
xmlns:app="http://schemas.android.com/apk/res-auto">
<com.scwang.smartrefresh.layout.SmartRefreshLayout
android:id="@+id/refresh_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:srlEnableLoadMore="true"
app:srlEnableRefresh="false">
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/rv_recommend"
android:layout_marginHorizontal="@dimen/dp_5"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<com.kongfz.app.core.ui.widget.loading.RefreshFooterView2
android:background="@color/gray_4"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</com.scwang.smartrefresh.layout.SmartRefreshLayout>
<!--分类列表接口错误的时候显示的骨架屏-->
<androidx.core.widget.NestedScrollView
android:id="@+id/sv_ste"
android:visibility="gone"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:background="@color/gold_dark"
android:orientation="vertical"
android:id="@+id/ll_ste"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</androidx.core.widget.NestedScrollView>
<!--分类列表接口返回data为[]时显示的空页面-->
<androidx.core.widget.NestedScrollView
android:visibility="gone"
android:background="@color/white"
android:id="@+id/sv_empty_list"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
android:layout_width="match_parent"
android:layout_height="match_parent">
<RelativeLayout
android:id="@+id/rl_empty_list"
android:layout_width="match_parent"
android:layout_height="match_parent">
</RelativeLayout>
</androidx.core.widget.NestedScrollView>
</RelativeLayout>