Android项目2之横屏和竖屏切换

xml代码

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

    <Button
        android:id="@+id/change"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="改变屏幕方向为横屏显示（当前为竖屏显示）" />

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

</LinearLayout>

 

 

 

java代码：

package cn.chenzhenhua.www.helloworld;

import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.content.res.Configuration;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends Activity {
 
 private Button chane=null;
 private ImageView img=null;
 
 private static final String TAG = "zhua";
 
 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  
  this.chane=(Button)super.findViewById(R.id.change);
  this.img=(ImageView)super.findViewById(R.id.img);
  this.chane.setOnClickListener(new OnClickListener(){

   @Override
   public void onClick(View v) {
    // TODO Auto-generated method stub
    Log.i(TAG,"MyOnClickListener");
    
    if (MainActivity.this.getRequestedOrientation() == ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED) {
     MainActivity.this.chane.setText("错误：无法改变屏幕方向！");
    } else {
     if (MainActivity.this.getRequestedOrientation() == ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE) {
      // 当前屏幕为横屏显示
      MainActivity.this
        .setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
     } else if (MainActivity.this.getRequestedOrientation() == ActivityInfo.SCREEN_ORIENTATION_PORTRAIT) {
      // 当前屏幕为横屏显示
      MainActivity.this
        .setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);

     }
    }
   }
   
  });
  
 }
 
 @Override
 public void onConfigurationChanged(Configuration newConfig) {
  // 系统设置改变时触发
  
  Log.i(TAG,"onConfigurationChanged");
  
  if (newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE) {
   Log.i(TAG,"当前屏幕方向为横屏");
   MainActivity.this.chane.setText("改变屏幕方向为竖屏显示（当前屏幕为横屏）");
   MainActivity.this.img.setImageResource(R.drawable.error);
  } else if (newConfig.orientation == Configuration.ORIENTATION_PORTRAIT) {
   Log.i(TAG,"当前屏幕方向为竖屏");
   MainActivity.this.chane.setText("改变屏幕方向为横屏显示（当前屏幕为竖屏）");
   MainActivity.this.img.setImageResource(R.drawable.ok);
  }
  
  super.onConfigurationChanged(newConfig);
 };
}

 

 

配置文件代码：

 <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name"
            android:configChanges="orientation|keyboard|keyboardHidden|screenSize"
            android:screenOrientation="portrait">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

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

 

 

效果图：

 

 

注意

onConfigurationChanged在Android4.0中不执行解决办法：

 

首先在manifest文件中配置了android:configChanges="orientation|keyboard"，然后在Activity中Override了onConfigurationChanged方法，但是无论怎么着，这个方法就是不执行
今天找到解决方法，要在configChanges中加screenSize这个属性才回执行到onConfigurationChanged
android:configChanges="orientation|keyboard|keyboardHidden|screenSize"