public float weight
Added in API level 1
Indicates how much of the extra space in the LinearLayout will be allocated to the view associated with these LayoutParams. Specify 0 if the view should not be stretched. Otherwise the extra pixels
will be pro-rated among all views whose weight is greater than 0.
表明了在LinearLayout中，Weight决定了可以分配给View的空间。如果为0（默认）View不拉伸，其他情况下按照Weight去分配View的空间。
既然表明与LinearLayout.LayoutParams有关
public LinearLayout.LayoutParams (int width, int height, float weight)
结合Width，Height，Weight做了如下图的简单demo，表明并不是weight小的，占用的空间一定大。
六个Demo依次的顺序为：
1.
android:orientation="horizontal"（父线性容器）
android:layout_width="match_parent"
android:layout_height="match_parent"
2.
android:orientation="horizontal"（父线性容器）
android:layout_width="0dp"
android:layout_height="match_parent"
3.
android:orientation="vertical"（父线性容器）
android:layout_width="match_parent"
android:layout_height="match_parent"
4.
android:orientation="vertical"（父线性容器）
android:layout_width="match_parent"
android:layout_height="0dp"
5.
android:orientation="horizontal"（父线性容器）
android:layout_width="match_parent"
android:layout_height="wrap_content"
6.
android:orientation="vertical"（父线性容器）
android:layout_width="wrap_content"
android:layout_height="match_parent"
<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"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="3dp"
android:layout_weight="1"
android:background="#999555"
android:orientation="horizontal" >
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1"
android:background="#123456"
android:gravity="center"
android:text="weight = 1"
android:textColor="#FFFFFF" />
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="2"
android:background="#654321"
android:gravity="center"
android:text="weight = 2"
android:textColor="#FFFFFF" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="3dp"
android:layout_weight="1"
android:background="#999555"
android:orientation="horizontal" >
<TextView
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="1"
android:background="#123456"
android:gravity="center"
android:text="weight = 1"
android:textColor="#FFFFFF" />
<TextView
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="2"
android:background="#654321"
android:gravity="center"
android:text="weight = 2"
android:textColor="#FFFFFF" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="3dp"
android:layout_weight="1"
android:background="#999555"
android:orientation="vertical" >
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1"
android:background="#123456"
android:gravity="center"
android:text="weight = 1"
android:textColor="#FFFFFF" />
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="2"
android:background="#654321"
android:gravity="center"
android:text="weight = 2"
android:textColor="#FFFFFF" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="3dp"
android:layout_weight="1"
android:background="#999555"
android:orientation="vertical" >
<TextView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="#123456"
android:gravity="center"
android:text="weight = 1"
android:textColor="#FFFFFF" />
<TextView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="2"
android:background="#654321"
android:gravity="center"
android:text="weight = 2"
android:textColor="#FFFFFF" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="3dp"
android:layout_weight="1"
android:background="#999555"
android:orientation="horizontal" >
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:background="#123456"
android:gravity="center"
android:text="weight = 1"
android:textColor="#FFFFFF" />
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="2"
android:background="#654321"
android:gravity="center"
android:text="weight = 2"
android:textColor="#FFFFFF" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="3dp"
android:layout_weight="1"
android:background="#999555"
android:orientation="vertical" >
<TextView
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:background="#123456"
android:gravity="center"
android:text="weight = 1"
android:textColor="#FFFFFF" />
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="2"
android:background="#654321"
android:gravity="center"
android:text="weight = 2"
android:textColor="#FFFFFF" />
</LinearLayout>
</LinearLayout>