Android如何从代码向另一个LinearLayout添加Linearlayout

Question

I have a LinearLayout in main.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    android:id="@+id/mainLayout" >

</LinearLayout>

I have made another XML file, called item_box.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/linearLayout1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/item_bg"
    android:gravity="right" >

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/icon" />

    <CheckBox
        android:id="@+id/checkBox1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginRight="20dp"
        android:text="@string/item1"
        android:textSize="30dp" />

    <TextView
        android:id="@+id/textView1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginRight="20dp"
        android:gravity="right"
        android:text="@string/number1"
        android:textColor="@color/number_bg"
        android:textSize="30dp" />

</LinearLayout>

Basically, what I want to do from the code (programmatically), is add a couple item_box.xml into the main.xml. How can I accomplish this?

Answer 1

LinearLayout mainLayout = (LinearLayout)findViewById(R.id.main);
LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View itemBox = inflater.inflate(R.layout.item_box);
mainLayout.addView(itemBox);

Answer 2

try this linearlayout inside another linearlayout add id to linearlayout layout1.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/firstlayout"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

</LinearLayout>

in oncreate() call

LinearLayout firstlayout=(LinearLayout)findviewbyId(R.id.firstlayout);
LinearLayout secondlayoout=(LinearLayout)this.getLayoutInflater().inflate(R.layout.layout2,null); //inflating view from xml 
TextView btn1=(TextView)secondlayoout.findviewbyId(R.id.button1);
btn1.settext("TEST");
firstlayout.addview(secondlayoout);

Answer 3

You are getting a Nullpointer because linearLayout1 is not in mainLayout. You need to inflate your view first and then add it. You should read this question I think it will help you.

Answer 4

Use LayoutInflater :

LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View itemBox = inflater.inflate(R.layout.item_box);