当我将其设置为匹配父级时，页面必须填充整个 ViewPager2（使用 match_parent）答案

【问题标题】：Pages must fill the whole ViewPager2 (use match_parent) while i set it to match parent当我将其设置为匹配父级时，页面必须填充整个 ViewPager2（使用 match_parent）
【发布时间】：2020-11-16 22:46:53
【问题描述】：

我在我的应用程序中使用viewPager2 和custom adapter，在布局中我在linearLayout 中使用我的viewpager2。我将我的viewpager2 的height 和width 设置为matchParent，我还在Java 代码中将其设置为matchParent，并将attachToRoot 设置为false，但是当我仍然收到此错误时我午餐我的应用程序。我该如何解决这个问题？

这是我的布局：

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <View
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1" />

    <androidx.viewpager2.widget.ViewPager2
        android:id="@+id/vp_home"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="0.7"
        android:clipToPadding="false"
        android:paddingStart="20dp"
        android:paddingEnd="20dp"/>

    <View
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1" />

</LinearLayout>

这是我的 viewpager2 代码：

mAdapter = new adapter_vp2_home(getActivity(), ls);

    vp_home.setLayoutParams(new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
    vp_home.setOrientation(ViewPager2.ORIENTATION_HORIZONTAL);

    vp_home.setAdapter(mAdapter);

这是日志：

java.lang.IllegalStateException: Pages must fill the whole ViewPager2 (use match_parent)
        at androidx.viewpager2.widget.ViewPager2$4.onChildViewAttachedToWindow(ViewPager2.java:270)
        at androidx.recyclerview.widget.RecyclerView.dispatchChildAttached(RecyclerView.java:7713)
        at androidx.recyclerview.widget.RecyclerView$5.addView(RecyclerView.java:857)
        at androidx.recyclerview.widget.ChildHelper.addView(ChildHelper.java:107)
        at androidx.recyclerview.widget.RecyclerView$LayoutManager.addViewInt(RecyclerView.java:8753)
        at androidx.recyclerview.widget.RecyclerView$LayoutManager.addView(RecyclerView.java:8711)
        at androidx.recyclerview.widget.RecyclerView$LayoutManager.addView(RecyclerView.java:8699)
        at androidx.recyclerview.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1645)
        at androidx.recyclerview.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1591)
        at androidx.recyclerview.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:668)
        at androidx.recyclerview.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:4141)
        at androidx.recyclerview.widget.RecyclerView.dispatchLayout(RecyclerView.java:3853)
        at androidx.recyclerview.widget.RecyclerView.onLayout(RecyclerView.java:4410)
        at android.view.View.layout(View.java:20857)
        at android.view.ViewGroup.layout(ViewGroup.java:6401)
        at androidx.viewpager2.widget.ViewPager2.onLayout(ViewPager2.java:526)
        at android.view.View.layout(View.java:20857)
        at android.view.ViewGroup.layout(ViewGroup.java:6401)
        at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1791)
        at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1635)
        at android.widget.LinearLayout.onLayout(LinearLayout.java:1544)
        at android.view.View.layout(View.java:20857)
        at android.view.ViewGroup.layout(ViewGroup.java:6401)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at android.view.View.layout(View.java:20857)
        at android.view.ViewGroup.layout(ViewGroup.java:6401)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at android.view.View.layout(View.java:20857)
        at android.view.ViewGroup.layout(ViewGroup.java:6401)
        at androidx.constraintlayout.widget.ConstraintLayout.onLayout(ConstraintLayout.java:1855)
        at android.view.View.layout(View.java:20857)
        at android.view.ViewGroup.layout(ViewGroup.java:6401)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at android.view.View.layout(View.java:20857)
        at android.view.ViewGroup.layout(ViewGroup.java:6401)
        at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1791)
        at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1635)
        at android.widget.LinearLayout.onLayout(LinearLayout.java:1544)
        at android.view.View.layout(View.java:20857)
        at android.view.ViewGroup.layout(ViewGroup.java:6401)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at android.view.View.layout(View.java:20857)
        at android.view.ViewGroup.layout(ViewGroup.java:6401)
        at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1791)
        at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1635)
        at android.widget.LinearLayout.onLayout(LinearLayout.java:1544)
        at android.view.View.layout(View.java:20857)
        at android.view.ViewGroup.layout(ViewGroup.java:6401)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at com.android.internal.policy.DecorView.onLayout(DecorView.java:945)
        at android.view.View.layout(View.java:20857)
        at android.view.ViewGroup.layout(ViewGroup.java:6401)
        at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2961)
E/AndroidRuntime:     at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2648)
        at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1785)
        at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:7832)
        at android.view.Choreographer$CallbackRecord.run(Choreographer.java:911)
        at android.view.Choreographer.doCallbacks(Choreographer.java:723)
        at android.view.Choreographer.doFrame(Choreographer.java:658)
        at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:897)
        at android.os.Handler.handleCallback(Handler.java:789)
        at android.os.Handler.dispatchMessage(Handler.java:98)
        at android.os.Looper.loop(Looper.java:164)
        at android.app.ActivityThread.main(ActivityThread.java:6944)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)

【问题讨论】：

请发布完整的堆栈跟踪日志
@Zain 我编辑我的帖子。
尝试在LinearLayout上设置android:layout_width="wrap_content"
@Zain 我试了一下，但它给了我同样的错误和日志
为什么权重 android:layout_weight="0.7"？

标签： java android xml android-studio android-viewpager2

【解决方案1】：

为视图设置 LayoutParams：

view.setLayoutParams(new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));

不是vp_home.setLayoutParams，删掉就好了

【讨论】：

【解决方案2】：

我只是通过匹配我的自定义 viewpager2 的自定义布局来解决这个问题

【讨论】：

【解决方案3】：

对我来说，我的视图布局应该只有match_parent。

【讨论】：

【解决方案4】：

您可以在 自定义布局 XML 文件中将 wrap_content 更改为 match_parent。它对我有用。

<LinearLayout 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"
    android:orientation="vertical"
    tools:context=".fragment.PracticeFragment">

【讨论】：