Activity中ConfigChanges屬性的用法

 通過設置這個屬性可以使Activity捕捉設備狀態變化，以下是可以被識別的內容：  
CONFIG_FONT_SCALE
CONFIG_MCC
CONFIG_MNC
CONFIG_LOCALE
CONFIG_TOUCHSCREEN
CONFIG_KEYBOARD
CONFIG_NAVIGATION
CONFIG_ORIENTATION

設置方法：將下列字段用“|”符號分隔開，例如：“locale|navigation|orientation
”

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</tr> </tbody> </table> 通過一個例子介紹這個屬性的用法： 首先需要修改項目的manifest:
?View Code XML

Value	Description
“mcc“	The IMSI mobile country code (MCC) has changed — that is, a SIM hasbeen detected and updated the MCC.移動國家號碼，由三位數字組成，每個國家都有自己獨立的MCC，可以識別手機用戶所屬國家。
“mnc“	The IMSI mobile network code (MNC) has changed — that is, a SIM hasbeen detected and updated the MNC.移動網號，在一個國家或者地區中，用于區分手機用戶的服務商。
“locale“	The locale has changed — for example, the user has selected a new language that text should be displayed in.用戶所在地區發生變化。
“touchscreen“	The touchscreen has changed. (This should never normally happen.)
“keyboard“	The keyboard type has changed — for example, the user has plugged in an external keyboard.鍵盤模式發生變化，例如：用戶接入外部鍵盤輸入。
“keyboardHidden“	The keyboard accessibility has changed — for example, the user has slid the keyboard out to expose it.用戶打開手機硬件鍵盤
“navigation“	The navigation type has changed. (This should never normally happen.)
“orientation“	The screen orientation has changed — that is, the user has rotated the device.設備旋轉，橫向顯示和豎向顯示模式切換。
“fontScale“	The font scaling factor has changed — that is, the user has selected a new global font size.全局字體大小縮放發生改變

</tr> </tbody> </table>
在Activity中添加了 android:configChanges屬性，目的是當所指定屬性(Configuration Changes)發生改變時，通知程序調用 onConfigurationChanged()函數。 創建一個Layout UI:
?View Code XML

<manifest xmlns:android="http://schemas.android.com/apk/res/android"       package="com.androidres.ConfigChangedTesting"       android:versionCode="1"       android:versionName="1.0.0">     <application android:icon="@drawable/icon" android:label="@string/app_name">         <activity android:name=".ConfigChangedTesting"                   android:label="@string/app_name"                   android:configChanges="keyboardHidden|orientation">             <intent-filter>                 <action android:name="android.intent.action.MAIN" />                 <category android:name="android.intent.category.LAUNCHER" />             </intent-filter>         </activity>     </application> </manifest>

</tr> </tbody> </table>

這個簡單的UI包含兩個按鈕，其中一個是通過Contact列表選擇一個聯系人，另外一個是查看當前選擇聯系人的詳細內容。

項目的Java源代碼：
import android.app.Activity;
import android.content.Intent;
import android.content.res.Configuration;
import android.net.Uri;
import android.os.Bundle;
import android.provider.Contacts.People;
import android.view.View;
import android.widget.Button;

public class ConfigChangedTesting extends Activity {
    /** Called when the activity is first created. */
    static final int PICK_REQUEST = 1337;
    Button viewButton=null;
    Uri contact = null;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //setContentView(R.layout.main);

        setupViews();
    }

    public void onConfigurationChanged(Configuration newConfig) {
                 super.onConfigurationChanged(newConfig); 

                 setupViews();
    } 

    /* (non-Javadoc)
     * @see android.app.Activity#onActivityResult(int, int, android.content.Intent)
     */
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        // TODO Auto-generated method stub
        //super.onActivityResult(requestCode, resultCode, data);

        if(requestCode == PICK_REQUEST){

            if(resultCode==RESULT_OK){

                contact = data.getData();
                viewButton.setEnabled(true);
            }

        }

    }

    private void setupViews(){

        setContentView(R.layout.main);

        Button pickBtn = (Button)findViewById(R.id.pick);

        pickBtn.setOnClickListener(new View.OnClickListener(){

            public void onClick(View v) {
                // TODO Auto-generated method stub

                Intent i=new Intent(Intent.ACTION_PICK,People.CONTENT_URI);
                startActivityForResult(i,PICK_REQUEST);
            }
        });

        viewButton =(Button)findViewById(R.id.view); 

        viewButton.setOnClickListener(new View.OnClickListener() {
                    public void onClick(View view) {
                        startActivity(new Intent(Intent.ACTION_VIEW, contact));
                    }
        }); 

        viewButton.setEnabled(contact!=null);
    }
}

 

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"     android:orientation="vertical"     android:layout_width="fill_parent"     android:layout_height="fill_parent"     > <Button         android:id="@+id/pick"     android:layout_width="fill_parent"     android:layout_height="wrap_content"     android:text="Pick"     /> <Button         android:id="@+id/view"     android:layout_width="fill_parent"     android:layout_height="wrap_content"     android:text="View"     /> </LinearLayout>