Android configuration使用 为什么监听事件onConfigurationChanged没有反应

Configuration专门描述手机设备的配置信息:

获取Configuration对象的方法 getResources().getConfiguration();

可以获取手机屏幕的方向 字体缩放因子等

解决onConfigurationChanged 回调事件没有反应

主要的原因是4.0以上的原因(menu显示图片 也是4.0以上不行)

package com.example.configuration;

import android.app.Activity;
import android.content.res.Configuration;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends Activity {

	private Configuration config;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		config = getResources().getConfiguration();
		Log.i("info", config.fontScale+"");
		Log.i("info", config.hardKeyboardHidden+"");
		Log.i("info", config.orientation+"");
		
		Button btn_change = (Button) findViewById(R.id.change);
		btn_change.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				int a = config.orientation;
				switch (a) {
				case Configuration.ORIENTATION_PORTRAIT:
					MainActivity.this.setRequestedOrientation(0);
					break;
				case Configuration.ORIENTATION_LANDSCAPE:
					MainActivity.this.setRequestedOrientation(1);
					break;
				default:
					break;
				}
			}
		});
	}
	@Override
	public void onConfigurationChanged(Configuration newConfig) {
		// TODO Auto-generated method stub
		super.onConfigurationChanged(newConfig);
		Log.i("info", "change");
	}
	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}

	@Override
	public boolean onOptionsItemSelected(MenuItem item) {
		// Handle action bar item clicks here. The action bar will
		// automatically handle clicks on the Home/Up button, so long
		// as you specify a parent activity in AndroidManifest.xml.
		int id = item.getItemId();
		if (id == R.id.action_settings) {
			return true;
		}
		return super.onOptionsItemSelected(item);
	}
}

可以看到屏幕在变化但是 没有打印log

我们需要在Manifest.xml文件中修改

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

    <uses-sdk
        android:minSdkVersion="14"
        android:targetSdkVersion="21" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:configChanges="orientation|screenSize"
            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>

发现添不添加 

<uses-permission android:name="android.permission.CHANGE_CONFIGURATION"/>

这个权限是无所谓的,不知道为什么

Activity中多添加一个screenSize

 android:configChanges="orientation|screenSize"

添加完成就可以看到打印的Log了