我正在尝试在我的APP上添加刷新视图。问题是每当我尝试在选项卡之间切换时。 SwipeRefresh激活。我尝试将其移至代码的几个部分,但仍然可以做到这一点。我尝试将SwipeRefreshlayout移到我的一个片段上,并且使用空指针崩溃。并且即使我刷新该片段也无法识别它。
我的最新尝试是将整个containt_main.xml作为我的滑动刷新。并尝试在标签之间移动时再次激活
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.SwipeRefreshLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/refresh">
<android.support.v4.widget.DrawerLayout
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/main_content"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:ads="http://schemas.android.com/apk/res-auto"
android:fitsSystemWindows="true"
>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?android:attr/actionBarSize"
android:background="@color/colorPrimary"
android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
android:elevation="4dp" />
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v4.view.ViewPager
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_behavior="@string/appbar_scrolling_view_behavior" >
<android.support.design.widget.TabLayout
android:id="@+id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:tabGravity="fill"
app:tabMode="scrollable"
app:tabTextAppearance="@android:style/TextAppearance.Widget.TabWidget" />
</android.support.v4.view.ViewPager>
</RelativeLayout>
<FrameLayout
android:id="@+id/fragment_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="20dp"/>
</LinearLayout>
<android.support.design.widget.NavigationView
android:id="@+id/navigation_view"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="start"
app:headerLayout="@layout/nav_header"
app:menu="@menu/drawer_menu"
/>
</android.support.v4.widget.DrawerLayout >
</android.support.v4.widget.SwipeRefreshLayout>
我的片段XML。
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="MainActivity"
android:layout_below="@+id/cardview">
<android.support.v7.widget.RecyclerView
android:id="@+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentTop="true"
/>
</LinearLayout>
此代码块在我的mainactivity Reader中。class读取XML xml并将其保存在数据库中。
final SwipeRefreshLayout swipeRefreshLayout = findViewById(R.id.refresh);
swipeRefreshLayout.setColorSchemeResources(R.color.colorPrimary,R.color.colorPrimaryDark,R.color.colorAccent);
swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
@Override
public void onRefresh() {
swipeRefreshLayout.setRefreshing(true);
(new Handler()).postDelayed(new Runnable() {
@Override
public void run() {
swipeRefreshLayout.setRefreshing(false);
Reader fromthepast = new Reader(getApplicationContext(), "RSSLINK (censored)", "fromthepast");
fromthepast.execute();
}
},3000);
}
});
}
我在片段上放了我的刷新监听器。
@Override
public void onRefresh() {
getFragmentManager()
.beginTransaction()
.detach(this)
.attach(this)
.commit();
}
错误日志
> E/AndroidRuntime: FATAL EXCEPTION: main
> Process: com.lemesosblog.lemesosblog, PID: 27482
> java.lang.NullPointerException: Attempt to invoke virtual method 'void
> android.support.v4.widget.SwipeRefreshLayout.setColorSchemeResources(int[])'
> on a null object reference
> at com.lemesosblog.lemesosblog.Fragment.fromthepast_Fragment.onCreateView(fromthepast_Fragment.java:46)
> at android.support.v4.app.Fragment.performCreateView(Fragment.java:2346)
> at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1428)
> at android.support.v4.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1759)
> at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1827)
> at android.support.v4.app.BackStackRecord.executeOps(BackStackRecord.java:797)
> at android.support.v4.app.FragmentManagerImpl.executeOps(FragmentManager.java:2596)
> at android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2383)
> at android.support.v4.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManager.java:2338)
> at android.support.v4.app.FragmentManagerImpl.execSingleAction(FragmentManager.java:2215)
> at android.support.v4.app.BackStackRecord.commitNowAllowingStateLoss(BackStackRecord.java:649)
> at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:145)
> at android.support.v4.view.ViewPager.populate(ViewPager.java:1238)
> at android.support.v4.view.ViewPager.setCurrentItemInternal(ViewPager.java:663)
> at android.support.v4.view.ViewPager.setCurrentItemInternal(ViewPager.java:625)
> at android.support.v4.view.ViewPager.setCurrentItem(ViewPager.java:606)
> at android.support.design.widget.TabLayout$ViewPagerOnTabSelectedListener.onTabSelected(TabLayout.java:2170)
> at android.support.design.widget.TabLayout.dispatchTabSelected(TabLayout.java:1165)
> at android.support.design.widget.TabLayout.selectTab(TabLayout.java:1158)
> at android.support.design.widget.TabLayout.selectTab(TabLayout.java:1128)
> at android.support.design.widget.TabLayout$Tab.select(TabLayout.java:1427)
> at android.support.design.widget.TabLayout$TabView.performClick(TabLayout.java:1537)
> at android.view.View$PerformClick.run(View.java:24828)
> at android.os.Handler.handleCallback(Handler.java:789)
> at android.os.Handler.dispatchMessage(Handler.java:98)
> at android.os.Looper.loop(Looper.java:164)
> at android.app.ActivityThread.main(ActivityThread.java:6798)
> at java.lang.reflect.Method.invoke(Native Method)
> at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
> at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
> D/OSTracker: OS Event: crash Application terminated.
答案 0 :(得分:0)
请勿将SwipeRefreshLayout
用作父项
您必须为每个SwipeRefreshLayout
添加RecyclerView
fragment.xml
<android.support.v4.widget.SwipeRefreshLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/refresh1">
<android.support.v7.widget.RecyclerView
android:id="@+id/recyclerView1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentTop="true"/>
</android.support.v4.widget.SwipeRefreshLayout>