LinearLayout中的重力 - android？

Question

我創建波紋管佈局：

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout 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:id="@+id/relativeStart" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:background="@drawable/back" 
    tools:context=".SongsActivity"> 

    <LinearLayout 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     android:background="@drawable/header" 
     android:orientation="vertical"> 

     <LinearLayout 
      android:layout_width="match_parent" 
      android:layout_height="0dp" 
      android:layout_weight="1" 
      android:orientation="horizontal"> 

      <ImageButton 
       android:layout_width="wrap_content" 
       android:layout_height="wrap_content" 
       android:background="@null" 
       android:src="@drawable/felesh_m" /> 

      <LinearLayout 
       android:layout_width="wrap_content" 
       android:layout_height="match_parent" 
       android:layout_gravity="center_horizontal|center_vertical" 
       android:gravity="center_horizontal|center_vertical" 
       android:orientation="vertical"> 

       <ImageButton 
        android:id="@+id/imbCenter" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:layout_gravity="center_horizontal|center_vertical" 
        android:background="@null" 
        android:src="@drawable/hosein_hlarge" /> 
      </LinearLayout> 

      <ImageButton 
       android:layout_width="wrap_content" 
       android:layout_height="wrap_content" 
       android:background="@null" 
       android:src="@drawable/felesh_m" /> 
     </LinearLayout> 

     <android.support.v7.widget.RecyclerView 
      android:layout_width="match_parent" 
      android:layout_height="0dp" 
      android:layout_weight="4" /> 
    </LinearLayout> 
</RelativeLayout> 

參見下文圖片：

Answer 1

更改您的佈局，因爲這。你不需要採取多個Linear Layouts。因爲這對性能不利。所以我已經將它改爲Linear Layout以及一些Weight屬性。

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout 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:id="@+id/relativeStart" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:background="@drawable/common_ic_googleplayservices"> 

    <LinearLayout 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     android:background="@drawable/common_ic_googleplayservices" 
     android:orientation="vertical"> 

    <LinearLayout 
      android:layout_width="match_parent" 
      android:layout_height="0dp" 
      android:layout_weight="3" 
      android:orientation="horizontal"> 

      <ImageButton 
       android:layout_width="0dp" 
       android:layout_height="wrap_content" 
       android:layout_weight="0.50" 
       android:background="@null" 
       android:src="@drawable/common_ic_googleplayservices" /> 


      <ImageButton 
       android:id="@+id/imbCenter" 
       android:layout_width="0dp" 
       android:layout_height="wrap_content" 
       android:layout_weight="2" 
       android:background="@null" 
       android:src="@drawable/common_ic_googleplayservices" /> 

      <ImageButton 
       android:layout_width="0dp" 
       android:layout_height="wrap_content" 
       android:layout_weight="0.50" 
       android:background="@null" 
       android:src="@drawable/common_ic_googleplayservices" /> 
     </LinearLayout> 

     <android.support.v7.widget.RecyclerView 
      android:layout_width="match_parent" 
      android:layout_height="0dp" 
      android:layout_weight="4" /> 
    </LinearLayout> 
</RelativeLayout>