Question

Idea在RelativeLayout上的Touch侦听器的帮助下改变了自身的大小（宽度和高度）。 RelativeLayout里面的子节点是一个GridLayout，它本身由多个FrameLayouts组成（我猜这是不相关的）。 GridLayout的宽度和高度设置为match_parent（如RelativeLayout）。理论上，GridLayout应该根据运行时的父级进行更改。

但每当我尝试更改RelativeLayout的参数时，我都会收到以下错误消息：

android.widget.RelativeLayout $ LayoutParams无法强制转换为android.support.constraint.ConstraintLayout $ LayoutParams

以下是XML布局的相关部分

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 
    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">

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/maingrid">


        <GridLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:columnCount="4"
            android:rowCount="4"
            android:id="@+id/grid">

            <FrameLayout
                android:layout_width="0dp"
                android:layout_height="0dp"
                android:layout_columnWeight="1"
                android:layout_rowWeight="1">

这是代码

          private RelativeLayout Wall = findViewById(R.id.maingrid);

          Wall.setLayoutParams(new RelativeLayout.LayoutParams(newWidth,newHeight));

我试图将RelativeLayout.LayoutParams更改为其他尝试解决异常错误的类。但我只是得到了其他类似的异常错误。想想我可能会遗漏一些东西。

是否可以使用上面的XML Layout结构并在运行时生成所需的行为

被修改

也许我应该提到带有GridLayout的XML文件包含在

下面的主要布局中

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout 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"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context="com.example.lucy.pixelli.MainActivity"
    tools:showIn="@layout/activity_main">

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">
    </RelativeLayout>

    <include layout="@layout/grid" />

这是完整错误消息

FATAL EXCEPTION: main
Process: com.example.lucy.pixelli, PID: 11119
java.lang.ClassCastException: android.widget.RelativeLayout$LayoutParams cannot be cast to android.support.constraint.ConstraintLayout$LayoutParams
at android.support.constraint.ConstraintLayout.getViewWidget(ConstraintLayout.java:877)
at android.support.constraint.ConstraintLayout.setChildrenConstraints(ConstraintLayout.java:643)
at android.support.constraint.ConstraintLayout.updateHierarchy(ConstraintLayout.java:631)
at android.support.constraint.ConstraintLayout.onMeasure(ConstraintLayout.java:971)
at android.view.View.measure(View.java:19978)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6127)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at android.view.View.measure(View.java:19978)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6127)
at android.support.design.widget.CoordinatorLayout.onMeasureChild(CoordinatorLayout.java:714)
at android.support.design.widget.CoordinatorLayout.onMeasure(CoordinatorLayout.java:786)
at android.view.View.measure(View.java:19978)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6127)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at android.support.v7.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:139)
at android.view.View.measure(View.java:19978)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6127)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1464)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:758)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:640)
at android.view.View.measure(View.java:19978)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6127)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at android.view.View.measure(View.java:19978)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6127)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1464)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:758)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:640)
at android.view.View.measure(View.java:19978)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6127)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at com.android.internal.policy.DecorView.onMeasure(DecorView.java:694)
at android.view.View.measure(View.java:19978)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2405)
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1457)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1720)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1333)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6675)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:887)
at android.view.Choreographer.doCallbacks(Choreographer.java:699)
at android.view.Choreographer.doFrame(Choreographer.java:634)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:873)
at android.os.Handler.handleCallback(Handler.java:751)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6349)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:893)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:783)

Answer 1

您想将LayoutParams设置为RelativeLayout。

视图的

LayoutParams应该是该视图的父类型。

由于您的RelativeLayout包含在ConstraintLayout中，因此您的LayoutParams应为ConstraintLayout.LayoutParam。

对于只有LayoutParams的{{1}}，您只需使用width/height

如何更改具有GridLayout作为子项的RelativeLayout的宽度？

1 个答案: