Android learning-layout

Android layout

LinearLayout (linear layout)

RelativeLayout (relative layout)

TableLayout (table layout)

FrameLayout (frame layout)

AbsoluteLayout (absolute layout)

GridLayout (grid layout)

LinerLayout

Detailed explanation of weight attributes

实现代码

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    
    xmlns:tools="http://schemas.android.com/tools"    
    android:id="@+id/LinearLayout1"    
    android:layout_width="match_parent"    
    android:layout_height="match_parent"    
    android:orientation="horizontal">   
        
    <LinearLayout    
        android:layout_width="0dp"    
        android:layout_height="fill_parent"    
        android:background="#ADFF2F"     
        android:layout_weight="1"/>    
       
        
    <LinearLayout    
        android:layout_width="0dp"    
        android:layout_height="fill_parent"    
        android:background="#DA70D6"     
        android:layout_weight="2"/>    
        
</LinearLayout> 

实现效果

Divided by proportion 水平方向: Set the android: of the involved View width属性设置为0dp, and then set the proportion to the android weight attribute; by analogy 竖直方向, just set android: height为0dpand then the weight attribute!

RelativeLayout

组件属性

父容器定位属性示意图

兄弟组件定位

The so-called sibling components are components in the same level of container

Components 1 and 2 in the figure are sibling components, and component 3 and component 1 or component 2 are not sibling components, so component 3 cannot be positioned by component 1 or 2, such as layout_toleftof = "component 1", which will report an error of! Remember! The most classic example of the positioning of this brother component is the "Plum Blossom Layout".

//实现代码
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    
    xmlns:tools="http://schemas.android.com/tools"    
    android:id="@+id/RelativeLayout1"    
    android:layout_width="match_parent"    
    android:layout_height="match_parent" >    
    
    <!-- 这个是在容器中央的 -->    
        
    <ImageView    
        android:id="@+id/img1"     
        android:layout_width="80dp"    
        android:layout_height="80dp"    
        android:layout_centerInParent="true"    
        android:src="@drawable/pic1"/>    
        
    <!-- 在中间图片的左边 -->    
    <ImageView    
        android:id="@+id/img2"     
        android:layout_width="80dp"    
        android:layout_height="80dp"    
        android:layout_toLeftOf="@id/img1"    
        android:layout_centerVertical="true"    
        android:src="@drawable/pic2"/>    
        
    <!-- 在中间图片的右边 -->    
    <ImageView    
        android:id="@+id/img3"     
        android:layout_width="80dp"    
        android:layout_height="80dp"    
        android:layout_toRightOf="@id/img1"    
        android:layout_centerVertical="true"    
        android:src="@drawable/pic3"/>    
        
    <!-- 在中间图片的上面-->    
    <ImageView    
        android:id="@+id/img4"     
        android:layout_width="80dp"    
        android:layout_height="80dp"    
        android:layout_above="@id/img1"    
        android:layout_centerHorizontal="true"    
        android:src="@drawable/pic4"/>    
        
    <!-- 在中间图片的下面 -->    
    <ImageView    
        android:id="@+id/img5"     
        android:layout_width="80dp"    
        android:layout_height="80dp"    
        android:layout_below="@id/img1"    
        android:layout_centerHorizontal="true"    
        android:src="@drawable/pic5"/>    
    
</RelativeLayout>

TableLayout

属性图

How to determine the number of rows and columns

① If we add components directly to TableLayout, then this component will occupy a row! ! !

②If we want to have multiple components on a row, we must add a TableRow container and throw all the components into it!

③The number of components in the tablerow determines how many columns the row has, and the width of the column is determined by the widest cell in the column

④The layout_width attribute of tablerow, the default is fill_parent, we set it to other values ​​will not take effect! ! ! But layout_height is wrapten——content by default, but we can set the size ourselves!

⑤The width of the entire table layout depends on the width of the parent container (to occupy the parent container itself)

⑥You have to count how many rows you have, one row per tablerow, and one row for a single component! The number of columns depends on the number of components in tableRow, and the most component is the number of columns in TableLayout

三个常用属性

android:collapseColumns: Set 被隐藏the sequence number of the required column
android:shrinkColumns: Set 被收缩the column sequence number of the allowed column
android:stretchColumns: Set 被拉伸the column sequence number of the running column

The column numbers of 从0开始算the above three attributes are all , such as shrinkColunmns = "2", corresponding to the third column!
Yes 设置多个, use, for 逗号隔开example, "0,2". If all columns are valid, use "*".
In addition to these three common attributes, there are two other attributes, namely skip grid and merged cells, which are the same as HTML The Table in is similar:

android:layout_column="2":It means to skip the second one and display it directly to the third grid, counting from 1!: It
android:layout_span="4"means 合并4 cells, that is, this component occupies 4 cells

FrameLayout

Common attributes

Foreground image: The image that is always on the top of the frame layout and directly facing the user is the image that will not be overwritten.

• android:foreground :*Set the foreground image of the container for changing the frame layout
• android:foregroundGravity : Set the display position of the foreground image

GridLayout

Features

• You can set the arrangement of components in the layout yourself
• You can customize how many rows and columns the grid layout has
• You can directly set the component to be located in a certain row and certain column
• You can set the component to span several rows or columns

Attributes

AbsoluteLayout

几乎不做使用，略过