[Android] 开发第六天

Android 布局介绍

LinearLayout 线性布局

RelativeLayout 相对布局

TableLayout 表格布局

FrameLayout 帧布局

ConstraintLayout 弹性布局（新） 介绍：http://www.jianshu.com/p/32a0a6e0a98a

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 我目前使用的 Android-Studio 3.0 Canary 6 默认的布局使用的是 ConstraintLayout 弹性布局

<?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"
    tools:context="com.oazzz.test5.MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>

此时的界面效果和其它布局看不出什么不同：

按 http://www.jianshu.com/p/32a0a6e0a98a 来个相对定位布局效果：

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
    android:id="@+id/constraintLayout"
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <Button
        android:id="@+id/cancel_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="16dp"
        android:layout_marginStart="16dp"
        android:text="取消"
        app:layout_constraintBottom_toBottomOf="@id/constraintLayout"
        app:layout_constraintStart_toStartOf="@id/constraintLayout"/>

    <Button
        android:id="@+id/next_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="16dp"
        android:layout_marginStart="16dp"
        android:text="下一步"
        app:layout_constraintBottom_toBottomOf="@id/constraintLayout"
        app:layout_constraintStart_toEndOf="@id/cancel_button"/>

</android.support.constraint.ConstraintLayout>

界面效果如图：  取消 按钮 左 16dp 下 16 dp ，下一步 按钮 左 16dp 下 16 dp 。

父容器可以直接指定ID（@id/constraintLayout），也可以使用 parent 代指。

 再来个比例布局效果：

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/constraintLayout"
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Center"
        app:layout_constraintEnd_toEndOf="@id/constraintLayout"
        app:layout_constraintStart_toStartOf="@id/constraintLayout"
        app:layout_constraintTop_toTopOf="@+id/constraintLayout"
        app:layout_constraintBottom_toBottomOf="@+id/constraintLayout"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Bias"
        app:layout_constraintEnd_toEndOf="@id/constraintLayout"
        app:layout_constraintStart_toStartOf="@id/constraintLayout"
        app:layout_constraintTop_toTopOf="@+id/constraintLayout"
        app:layout_constraintBottom_toBottomOf="@+id/constraintLayout"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintVertical_bias="0.25"/>

</android.support.constraint.ConstraintLayout>

界面效果如图： 其中 Center 按钮的全部边界与 父容器边界对齐，则显示为居中效果。

Bias 按钮对齐父容器后，再按比例布局，水平居中（靠左 1 / 2），垂直靠上 1 / 4 

还有对齐线：

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/constraintLayout"
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <android.support.constraint.Guideline
        android:id="@+id/guideLine"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        app:layout_constraintGuide_begin="50dp"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Guide Up"
        app:layout_constraintStart_toStartOf="@id/guideLine"
        app:layout_constraintTop_toTopOf="@+id/constraintLayout"
        app:layout_constraintBottom_toBottomOf="@+id/constraintLayout"
        app:layout_constraintVertical_bias="0.25"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Guide Down"
        app:layout_constraintStart_toStartOf="@id/guideLine"
        app:layout_constraintTop_toTopOf="@+id/constraintLayout"
        app:layout_constraintBottom_toBottomOf="@+id/constraintLayout"
        app:layout_constraintVertical_bias="0.5"/>

</android.support.constraint.ConstraintLayout>

界面效果如下图： 两个按钮左边距都按对齐线对齐，然后再按比例排列

自动填充：

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
    android:id="@+id/constraintLayout"
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <Button
        android:id="@+id/small"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Small"
        app:layout_constraintStart_toStartOf="@id/constraintLayout"
        app:layout_constraintTop_toTopOf="@id/constraintLayout"/>

    <Button
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:text="Large"
        app:layout_constraintBottom_toBottomOf="@id/constraintLayout"
        app:layout_constraintEnd_toEndOf="@id/constraintLayout"
        app:layout_constraintStart_toEndOf="@id/small"
        app:layout_constraintTop_toTopOf="@id/constraintLayout"/>

</android.support.constraint.ConstraintLayout>

界面效果如下图： Small 按钮位于父容器左上角，Large 按钮自动宽度，上下都与父容器对齐，显示为居中效果，左侧从 Small 结束位置开始，右侧对齐父容器。

比例缩放：

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
    android:id="@+id/constraintLayout"
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="0dp"
        android:layout_height="150dp"
        android:background="@color/colorAccent"
        android:src="@drawable/_06"
        app:layout_constraintLeft_toLeftOf="@+id/constraintLayout"
        app:layout_constraintRight_toRightOf="@+id/constraintLayout"
        app:layout_constraintTop_toTopOf="@+id/constraintLayout"
        app:layout_constraintDimensionRatio="16:9"/>

    <ImageView
        android:layout_width="150dp"
        android:layout_height="0dp"
        android:background="@color/colorPrimary"
        android:src="@drawable/_06"
        app:layout_constraintTop_toBottomOf="@id/imageView1"
        app:layout_constraintLeft_toLeftOf="@+id/constraintLayout"
        app:layout_constraintRight_toRightOf="@+id/constraintLayout"
        app:layout_constraintDimensionRatio="4:3"/>
</android.support.constraint.ConstraintLayout>

界面效果如下图： 图片1 按 16:9 缩放，图片2 按 4:3 缩放

还有 链样式，直接复制过来了

使用方式：

<TextView
    android:id="@+id/property_tv_cst_aries"
    style="@style/MemberWidget.Constellation"
    android:layout_marginLeft="@dimen/spacing_big"
    android:layout_marginTop="@dimen/spacing_medium"
    android:onClick="@{listener::onConstellationSelected}"
    android:text="白"
    app:layout_constraintHorizontal_chainStyle="spread_inside"
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintRight_toLeftOf="@+id/property_tv_cst_taurus"
    app:layout_constraintTop_toBottomOf="@id/property_tv_constellation" />

具体可参考：http://www.jianshu.com/p/32a0a6e0a98a