LayoutInflater.inflate详解

标签：布局   layout   android   layoutinflater   

介绍常见inflate方法

//1,通过系统服务获取布局加载器
LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);


View view = inflater.inflate(resource,root,attachToRoot);


//2,通过activity中的getLayoutInflater()方法
View view = getLayoutInflater().inflate(resource,root,attachToRoot);


//3,通过View的静态inflate()方法
View view = View.inflate(resource,root,attachToRoot);


//4,通过LayoutInflater的inflate()方法
View view = LayoutInflater.from(this).inflate(resource,root,attachToRoot);

 public View inflate(int resource, ViewGroup root) {
        return inflate(resource, root, root != null);
 }
 
 public View inflate(int resource, ViewGroup root, boolean attachToRoot) {
        if (DEBUG) System.out.println("INFLATING from resource: " + resource);
        XmlResourceParser parser = getContext().getResources().getLayout(resource);
        try {
            return inflate(parser, root, attachToRoot);
        } finally {
            parser.close();
        }
 }

针对传入的参数不同进行分析

if (root != null) {
if (DEBUG) {
System.out.println("Creating params from root: " +
                                    root);
}
// 如果root不等于null，获取它的LayoutParams
  params = root.generateLayoutParams(attrs);
if (!attachToRoot) {
//attachToRoot等于false，把root的LayoutParams属性给temp
temp.setLayoutParams(params);
}
}

//attachToRoot等于true，将temp加入到root这个viewGroup中
if (root != null && attachToRoot) {
root.addView(temp, params);
}


// root等于null，attachToRoot等于false，直接把temp赋值给返回结果
if (root == null || !attachToRoot) {
  result = temp;
}

根据不同的传值进行实现

<RelativeLayout 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"
    tools:context=".MyActivity">


    <TextView
        android:text="@string/hello_world"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />


</RelativeLayout>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="120dp"
    android:layout_height="120dp"
    android:background="@color/blue">


    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="hello inflate"
        android:textColor="@android:color/white" />


</LinearLayout>

protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
    view = getLayoutInflater().inflate(R.layout.view, null, false);
    setContentView(view);
}

protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
    view = getLayoutInflater().inflate(R.layout.view, null, true);
    setContentView(view);
}

protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
rootView = getLayoutInflater().inflate(R.layout.activity_my, null);
    view = getLayoutInflater().inflate(R.layout.view,(ViewGroup)rootView,false);
    setContentView(view);
}

protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
rootView = getLayoutInflater().inflate(R.layout.activity_my, null);
    view = getLayoutInflater().inflate(R.layout.view,(ViewGroup)rootView,true);
    setContentView(view);
}

这里因为root的布局为RelativeLayout，我们把view加入到root中，view本身保留了自有的LayoutParm

最后我要吐槽，为什么csdn不支持markdown，我都是先用Mou写好的，贴过来竟然要自己重新排版。。。

LayoutInflater.inflate详解

标签：布局   layout   android   layoutinflater   

原文地址：http://blog.csdn.net/kennethyo/article/details/40429031