记录ConstraintLayout2.0.0的一个坑

由于强迫症，总喜欢更新SDK，昨日闲来无事，将androidx.constraintlayout:constraintlayout：1.1.3更新到了 2.0.0-beta2接着就出现了诡异的问题

先上图

底部红色的部分没有文字显示，正常这里显示的是定位信息，很懵逼，之前还好好的，然后从布局开始调查，最简单的排除法，由于此子布局使用的是ConstraintLayout，也就是ConstraintLayout嵌套了一个ConstraintLayout子布局。最直观的方法，将子布局ConstraintLayout替换成随便什么布局，看看控件是否出现，Nice出现了，这样就确定了是我的子布局某些属性设置有问题了，应该是更新后有什么东西做了改动吧，实践出真知，还好属性少。

布局代码

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.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:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/tv_net_error_status"
        style="@style/common_text_content_default"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/home_error_net_status"
        android:drawableStart="@mipmap/home_ic_net_status"
        android:drawablePadding="@dimen/common_space_5"
        android:gravity="center_vertical"
        android:paddingStart="@dimen/common_space_10"
        android:background="@color/common_theme_color_light"
        android:paddingTop="@dimen/common_space_5"
        android:paddingBottom="@dimen/common_space_5"
        android:visibility="gone"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"/>

    <androidx.viewpager.widget.ViewPager
        android:id="@+id/view_pager"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        app:layout_constraintVertical_weight="10"
        app:layout_constraintBottom_toTopOf="@+id/bottom_navigation_bar"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent">

    </androidx.viewpager.widget.ViewPager>

    <com.ashokvarma.bottomnavigation.BottomNavigationBar
        android:id="@+id/bottom_navigation_bar"
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:background="@color/common_white"
        android:paddingTop="@dimen/common_space_5"
        app:layout_constraintVertical_weight="1"
        app:layout_constraintTop_toBottomOf="@+id/view_pager"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent">

    </com.ashokvarma.bottomnavigation.BottomNavigationBar>
    
    <androidx.constraintlayout.widget.ConstraintLayout
        android:id="@+id/upload_gps"
        android:background="@color/home_upload_info_bg"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:paddingTop="@dimen/common_space_5"
        android:paddingBottom="@dimen/common_space_5"
        android:paddingLeft="@dimen/common_space_10"
        android:paddingRight="@dimen/common_space_10"
        app:layout_constraintDimensionRatio="h, 10:1.15"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintBottom_toTopOf="@+id/bottom_navigation_bar">

        <TextView
            android:id="@+id/tv_title_time"
            style="@style/common_text_tag_white"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/home_local_time"
            android:gravity="center_vertical"
            app:layout_constraintTop_toTopOf="@id/upload_gps"
            app:layout_constraintLeft_toLeftOf="@id/upload_gps"
            app:layout_constraintBottom_toTopOf="@+id/tv_title_addr"/>

        <TextView
            android:id="@+id/tv_local_time"
            style="@style/common_text_tag_white"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_marginEnd="@dimen/common_space_10"
            android:gravity="center_vertical"
            app:layout_constraintHorizontal_weight="1"
            app:layout_constraintRight_toLeftOf="@+id/iv_local"
            app:layout_constraintLeft_toRightOf="@id/tv_title_time"
            app:layout_constraintTop_toTopOf="@id/upload_gps"
            app:layout_constraintBottom_toTopOf="@+id/tv_title_addr"/>

        <TextView
            android:id="@+id/tv_title_addr"
            style="@style/common_text_tag_white"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/home_local_addr"
            android:gravity="center_vertical"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintLeft_toLeftOf="@id/upload_gps"
            app:layout_constraintTop_toBottomOf="@+id/tv_title_time"/>

        <ImageView
            android:id="@+id/iv_local"
            android:layout_width="@dimen/home_local_ic_length"
            android:layout_height="@dimen/home_local_ic_length"
            app:srcCompat="@mipmap/home_ic_local_refresh"
            app:layout_constraintRight_toRightOf="@id/upload_gps"
            app:layout_constraintTop_toTopOf="@id/upload_gps"
            app:layout_constraintBottom_toBottomOf="@id/upload_gps"
            tools:ignore="ContentDescription" />

        <cn.com.drpeng.runman.common.widget.MarqueeTextView
            android:id="@+id/tv_local_addr"
            style="@style/common_text_tag_white"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_marginEnd="@dimen/common_space_10"
            android:gravity="center_vertical"
            app:layout_constraintHorizontal_weight="1"
            app:layout_constraintRight_toLeftOf="@+id/iv_local"
            app:layout_constraintBottom_toBottomOf="@id/upload_gps"
            app:layout_constraintLeft_toRightOf="@id/tv_title_addr"
            app:layout_constraintTop_toBottomOf="@+id/tv_local_time"/>

    </androidx.constraintlayout.widget.ConstraintLayout>

</androidx.constraintlayout.widget.ConstraintLayout>
           

首先再瞜一眼ConstraintLayout需要注意的坑，发现有人说嵌套ConstraintLayout子布局，子布局中控件约束不要用parent，要用子布局的id，这里我改了。先剧透，子布局id与parent其实一样，毫无影响，我之前用parent，约束的父布局就是这个ConstraintLayout子布局，不过也改成id了。懒得又改回去，这个问题排除。

接着又看到了google说使用ConstraintLayout，其中控件不建议使用match_parent，建议使用0dp，它相当于match_constraints，然后通过约束来控制控件的尺寸，than，我就将子布局的ConstraintLayout的match_parent改成了0dp，接着子布局中控件就神奇的出现了，本着不求甚解的原则，这个事儿就算过去了，记住了坑就好，原因就由大佬去研究吧，可以肯定的是升级版本后多了一些东西，不过目前没用到，所以暂时不研究。

<androidx.constraintlayout.widget.ConstraintLayout
        android:id="@+id/upload_gps"
        android:background="@color/home_upload_info_bg"
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:paddingTop="@dimen/common_space_5"
        android:paddingBottom="@dimen/common_space_5"
        android:paddingLeft="@dimen/common_space_10"
        android:paddingRight="@dimen/common_space_10"
        app:layout_constraintDimensionRatio="h, 10:1.15"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintBottom_toTopOf="@+id/bottom_navigation_bar">

        <TextView
            android:id="@+id/tv_title_time"
            style="@style/common_text_tag_white"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/home_local_time"
            android:gravity="center_vertical"
            app:layout_constraintTop_toTopOf="@id/upload_gps"
            app:layout_constraintLeft_toLeftOf="@id/upload_gps"
            app:layout_constraintBottom_toTopOf="@+id/tv_title_addr"/>

        <TextView
            android:id="@+id/tv_local_time"
            style="@style/common_text_tag_white"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_marginEnd="@dimen/common_space_10"
            android:gravity="center_vertical"
            app:layout_constraintHorizontal_weight="1"
            app:layout_constraintRight_toLeftOf="@+id/iv_local"
            app:layout_constraintLeft_toRightOf="@id/tv_title_time"
            app:layout_constraintTop_toTopOf="@id/upload_gps"
            app:layout_constraintBottom_toTopOf="@+id/tv_title_addr"/>

        <TextView
            android:id="@+id/tv_title_addr"
            style="@style/common_text_tag_white"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/home_local_addr"
            android:gravity="center_vertical"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintLeft_toLeftOf="@id/upload_gps"
            app:layout_constraintTop_toBottomOf="@+id/tv_title_time"/>

        <ImageView
            android:id="@+id/iv_local"
            android:layout_width="@dimen/home_local_ic_length"
            android:layout_height="@dimen/home_local_ic_length"
            app:srcCompat="@mipmap/home_ic_local_refresh"
            app:layout_constraintRight_toRightOf="@id/upload_gps"
            app:layout_constraintTop_toTopOf="@id/upload_gps"
            app:layout_constraintBottom_toBottomOf="@id/upload_gps"
            tools:ignore="ContentDescription" />

        <cn.com.drpeng.runman.common.widget.MarqueeTextView
            android:id="@+id/tv_local_addr"
            style="@style/common_text_tag_white"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_marginEnd="@dimen/common_space_10"
            android:gravity="center_vertical"
            app:layout_constraintHorizontal_weight="1"
            app:layout_constraintRight_toLeftOf="@+id/iv_local"
            app:layout_constraintBottom_toBottomOf="@id/upload_gps"
            app:layout_constraintLeft_toRightOf="@id/tv_title_addr"
            app:layout_constraintTop_toBottomOf="@+id/tv_local_time"/>

    </androidx.constraintlayout.widget.ConstraintLayout>
           

其实所有的坑都是因为我们不够了解