onCreateView方法何时被调用？和活动生命周期中有多少次？

Question

我写了一个看起来像这样的小程序:

package com.example.lifecycle;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.util.AttributeSet;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;

public class LifeLogger extends Activity {

    private String TAG = this.getClass().getName().toString();
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_life_logger);
        Log.d(TAG,"onCreate event");
    }
    @Override
    protected void onResume() {
        super.onResume();
        Log.d(TAG,"onResume event");
    }
    @Override
    protected void onPause() {
        super.onPause();
        Log.d(TAG,"onPause event");
    }
    @Override
    protected void onStop() {
        super.onStop();
        Log.d(TAG,"onStop event");
    }
    @Override
    protected void onRestart() {
        super.onRestart();
        Log.d(TAG,"onRestart event");
    }
    @Override
    public View onCreateView(String name, Context context, AttributeSet attrs) {
        Log.d(TAG,"onCreateView event");
        return super.onCreateView(name, context, attrs);
    }
    @Override
    protected void onStart() {
        super.onStart();
        Log.d(TAG,"onStart event");
    }
    @Override
    protected void onDestroy() {
        super.onDestroy();
        Log.d(TAG,"onDestroy event");
    }
}

这是主要的活动.

LogCat是:

06-11 07:07:10.033:D/com.example.lifecycle.LifeLogger(600):onCreateView事件06-11 07:07:10.033:D/com.example.lifecycle.LifeLogger(600):onCreateView事件06- 11 07:07:10.043:D/com.example.lifecycle.LifeLogger(600):onCreateView事件06-11 07:07:10.053:D/com.example.lifecycle.LifeLogger(600):onCreateView事件06-11 07 :07:10.063:D/com.example.lifecycle.LifeLogger(600):onCreateView事件06-11 07:07:10.063:D/com.example.lifecycle.LifeLogger(600):onCreateView事件06-11 07:07 :10.063:D/com.example.lifecycle.LifeLogger(600):onCreateView事件06-11 07:07:10.063:D/com.example.lifecycle.LifeLogger(600):onCreateView事件06-11 07:07:10.073 :D/com.example.lifecycle.LifeLogger(600):onCreateView事件06-11 07:07:10.073:D/com.example.lifecycle.LifeLogger(600):onCreateView事件06-11 07:07:10.083:D /com.example.lifecycle.LifeLogger(600):onCreateView事件06-11 07:07:10.083:D/com.example.lifecycle.LifeLogger(600):onCreateView事件06-11 07:07:10.083:D/com .example.lifecy cle.LifeLogger(600):onCreateView事件06-11 07:07:10.093:D/com.example.lifecycle.LifeLogger(600):onCreateView事件06-11 07:07:10.093:D/com.example.lifecycle. LifeLogger(600):onCreateView事件06-11 07:07:10.093:D/com.example.lifecycle.LifeLogger(600):onCreateView事件06-11 07:07:10.103:D/com.example.lifecycle.LifeLogger( 600):onCreateView事件06-11 07:07:10.113:D/com.example.lifecycle.LifeLogger(600):onCreateView事件06-11 07:07:10.113:D/com.example.lifecycle.LifeLogger(600) :onCreateView事件06-11 07:07:10.113:D/com.example.lifecycle.LifeLogger(600):onCreate事件06-11 07:07:10.113:D/com.example.lifecycle.LifeLogger(600):onStart事件06-11 07:07:10.113:D/com.example.lifecycle.LifeLogger(600):onResume事件06-11 07:07:10.193:D/com.example.lifecycle.LifeLogger(600):onCreateView事件06 -11 07:07:10.223:d/gralloc_goldfish(600):仿真器,而不GPU仿真检测.06-11 07:08:19.633:D/com.example.lifecycle.LifeLogger(600):onPause事件06-11 07:08:20.213:D/com.example.lifecycle.LifeLogger(600):onStop事件06- 11 07:08:31.993:D/com.example.lifecycle.LifeLogger(600):onRestart事件06-11 07:08:31.993:D/com.example.lifecycle.LifeLogger(600):onStart事件06-11 07 :08:31.993:D/com.example.lifecycle.LifeLogger(600):onResume事件06-11 07:08:51.073:D/com.example.lifecycle.LifeLogger(600):onPause事件06-11 07:08 :52.963:D/com.example.lifecycle.LifeLogger(600):onStop事件06-11 07:08:54.043:D/com.example.lifecycle.LifeLogger(600):onDestroy事件

这里发生了什么？为什么onCreateView被调用了这么多次？

onCreateView的时机是什么时候？

谢谢.

更新:

xml膨胀:

<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="${packageName}.${activityClass}" >

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

</RelativeLayout>

表现:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.lifecycle"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="15"
        android:targetSdkVersion="17" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.example.lifecycle.LifeLogger"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

在android api 16级上运行

Answer 1

你已经扩展了你的课程Activity.这意味着您班级的生命周期如下.

因此,onCreateView不是活动的生命周期方法.它只是一个成员方法,将用于doc中所述的指定任务.

与getSystemService返回的LayoutInflater充气时,标准实施android.view.LayoutInflater.Factory.onCreateView的使用.此实现不执行任何操作,适用于pre-android.os.Build.VERSION_CODES.HONEYCOMB应用程序.较新的应用程序应使用onCreateView(View,String,Context,AttributeSet).

依赖于Activity中onCreateView()的调用是不好的编程.

如果你使用Fragment扩展到你的类并且编写了onCreateView()方法,那么如果你仍在同一个片段上,它只会在你的onAttach()和onDestroyView()之后被调用两次.

见这个图.

在这里,它是Fragment的生命周期方法.

所以,你正在测试错误的假设.就这样!