PercentRelativeLayout在支持库26.0.0版中已弃用。

谷歌引入了新的名为ConstraintLayout的布局。

将库作为依赖项添加到模块级构建中。gradle文件:

     dependencies {
        compile 'com.android.support.constraint:constraint-layout:1.0.1'
      }

只需添加一个布局文件:

<?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"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
</android.support.constraint.ConstraintLayout>

约束

约束帮助您保持小部件的一致性。您可以使用锚(例如下面所示的约束句柄)来确定不同小部件之间的对齐规则。

Wrap Content: The view expands as needed to fit its contents. Match Constraints: The view expands as needed to meet the definition of its constraints after accounting for margins. However, if the given dimension has only one constraint, then the view expands to fit its contents. Using this mode on either the height or width also allows you to set a size ratio. Fixed: You specify a specific dimension in the text box below or by resizing the view in the editor. Spread: The views are evenly distributed (after margins are accounted for). This is the default. Spread inside: The first and last view are affixed to the constraints on each end of the chain and the rest are evenly distributed. Weighted: When the chain is set to either spread or spread inside, you can fill the remaining space by setting one or more views to "match constraints" (0dp). By default, the space is evenly distributed between each view that's set to "match constraints," but you can assign a weight of importance to each view using the layout_constraintHorizontal_weight and layout_constraintVertical_weight attributes. If you're familiar with layout_weight in a linear layout, this works the same way. So the view with the highest weight value gets the most amount of space; views that have the same weight get the same amount of space. Packed: The views are packed together (after margins are accounted for). You can then adjust the whole chain's bias (left/right or up/down) by changing the chain's head view bias. Center Horizontally or Center Vertically: To create a chain of views quickly, select them all, right-click one of the views, and then select either Center Horizontally or Center Vertically, to create either a horizontal or vertical chain Baseline alignment: Align the text baseline of a view to the text baseline of another view. Constrain to a guideline: You can add a vertical or horizontal guideline to which you can constrain views, and the guideline will be invisible to app users. You can position the guideline within the layout based on either dp units or percent, relative to the layout's edge. Adjust the constraint bias: When you add a constraint to both sides of a view (and the view size for the same dimension is either "fixed" or "wrap content"), the view becomes centered between the two constraints with a bias of 50% by default. You can adjust the bias by dragging the bias slider in the Properties window Set size as a ratio: You can set the view size to a ratio such as 16:9 if at least one of the view dimensions is set to "match constraints" (0dp).

你可以从官方医生那里了解更多。

你正在寻找android:layout_weight属性。它将允许你使用百分比来定义你的布局。

在下面的例子中，左键占用70%的空间，右键占用30%的空间。

<LinearLayout
    android:layout_width="match_parent" 
    android:layout_height="wrap_content"
    android:orientation="horizontal">

    <Button
        android:text="left" 
        android:layout_width="0dp" 
        android:layout_height="wrap_content" 
        android:layout_weight=".70" /> 

    <Button
        android:text="right" 
        android:layout_width="0dp" 
        android:layout_height="wrap_content" 
        android:layout_weight=".30" />

</LinearLayout>

它的工作原理与任何类型的视图相同，你可以用一些EditText替换按钮来满足你的需要。

请确保将layout_width设置为0dp，否则您的视图可能无法正确缩放。

注意，权重和不一定等于1，我只是觉得这样读起来更容易。你可以将第一个权重设置为7，第二个权重设置为3，结果是一样的。

您可以查看新的百分比支持库。

compile 'com.android.support:percent:22.2.0'

docs

样本

你可以通过布局权重来实现。权重决定了屏幕上无人认领的部分如何划分。给每个EditText一个0的layout_width和一些成比例的权重。也就是说，如果你想让第一个占用两倍的空间，给一个权重为2，给另一个权重为1。

不能在RelativeLayout中使用百分比来定义视图的维度。最好的方法是使用线性布局和权重，或自定义布局。

由于PercentRelativeLayout在26.0.0中已弃用，并且嵌套的布局，如RelativeLayout内部的LinearLayout对性能有负面影响(了解ConstraintLayout的性能优势)，为您实现百分比宽度的最佳选择是用ConstraintLayout替换您的RelativeLayout。

这个问题可以通过两种方式解决。

解决方案#1使用百分比偏移的指导方针

<android.support.constraint.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">

    <TextView
        android:id="@+id/host_label"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Host"
        android:layout_marginTop="16dp"
        android:layout_marginLeft="8dp"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toLeftOf="@+id/host_input" />

    <TextView
        android:id="@+id/port_label"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Port"
        android:layout_marginTop="16dp"
        android:layout_marginLeft="8dp"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toLeftOf="@+id/port_input" />

    <EditText
        android:id="@+id/host_input"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:layout_marginLeft="8dp"
        android:layout_marginRight="8dp"
        android:inputType="textEmailAddress"
        app:layout_constraintTop_toBottomOf="@+id/host_label"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toLeftOf="@+id/guideline" />

    <EditText
        android:id="@+id/port_input"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:layout_marginLeft="8dp"
        android:layout_marginRight="8dp"
        android:inputType="number"
        app:layout_constraintTop_toBottomOf="@+id/port_label"
        app:layout_constraintLeft_toLeftOf="@+id/guideline"
        app:layout_constraintRight_toRightOf="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_percent="0.8" />

</android.support.constraint.ConstraintLayout>

解决方案#2使用链与加权宽度的EditText

<android.support.constraint.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">

    <TextView
        android:id="@+id/host_label"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Host"
        android:layout_marginTop="16dp"
        android:layout_marginLeft="8dp"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toLeftOf="@+id/host_input" />

    <TextView
        android:id="@+id/port_label"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Port"
        android:layout_marginTop="16dp"
        android:layout_marginLeft="8dp"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toLeftOf="@+id/port_input" />

    <EditText
        android:id="@+id/host_input"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:layout_marginLeft="8dp"
        android:layout_marginRight="8dp"
        android:inputType="textEmailAddress"
        app:layout_constraintHorizontal_weight="0.8"
        app:layout_constraintTop_toBottomOf="@+id/host_label"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toLeftOf="@+id/port_input" />

    <EditText
        android:id="@+id/port_input"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:layout_marginLeft="8dp"
        android:layout_marginRight="8dp"
        android:inputType="number"
        app:layout_constraintHorizontal_weight="0.2"
        app:layout_constraintTop_toBottomOf="@+id/port_label"
        app:layout_constraintLeft_toRightOf="@+id/host_input"
        app:layout_constraintRight_toRightOf="parent" />

</android.support.constraint.ConstraintLayout>

在这两种情况下，你会得到这样的结果