2011年2月9日 星期三

Android - 儲存偏好設定(Preference)

1. 此範例是利用SharedPreferences來儲存使用者在某個程式內的偏好設定。

2. MainActivity.java
package org.me.android_preference;
import android.app.Activity;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class MainActivity extends Activity {
    private EditText nameEditText;
    private Button saveButton;
    private Button restoreButton;

    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);
        setContentView(R.layout.main);
        nameEditText = (EditText) findViewById(R.id.nameEditText);
        saveButton = (Button) findViewById(R.id.saveButton);
        restoreButton = (Button) findViewById(R.id.restoreButton);
        saveButton.setOnClickListener(saveClickListener);
        restoreButton.setOnClickListener(restoreClickListener);
    }

    //按下Save按鈕
    private Button.OnClickListener saveClickListener = new Button.OnClickListener() {

        public void onClick(View arg0) {
            //取得SharedPreference設定("Preference"為設定檔的名稱)
            SharedPreferences settings = getSharedPreferences("Preference", 0);
            //置入name屬性的字串
            settings.edit().putString("name", nameEditText.getText().toString()).commit();
        }
    };

    //按下Restore按鈕
    private Button.OnClickListener restoreClickListener = new Button.OnClickListener() {

        public void onClick(View arg0) {
            //取得SharedPreference設定("Preference"為設定檔的名稱)
            SharedPreferences settings = getSharedPreferences("Preference", 0);
            //取出name屬性的字串
            String name = settings.getString("name", "");
            nameEditText.setText(name);
        }
    };
}


3. main.xml(Layout)
<?xml version="1.0" encoding="utf-8"?>
<AbsoluteLayout
android:id="@+id/widget0"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android"
>
<TextView
android:id="@+id/nameView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Name:"
android:layout_x="22px"
android:layout_y="34px"
>
</TextView>
<EditText
android:id="@+id/nameEditText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="18sp"
android:layout_x="90px"
android:layout_y="20px"
>
</EditText>
<Button
android:id="@+id/saveButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Save"
android:layout_x="20px"
android:layout_y="86px"
>
</Button>
<Button
android:id="@+id/restoreButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Restore"
android:layout_x="98px"
android:layout_y="84px"
>
</Button>
</AbsoluteLayout>


4. 執行之後的畫面。(按下Store將Name的值儲存在偏好設定,按下Restore會將儲存在偏好設定的值取回)

2011年2月8日 星期二

Android WIFI控制(開啟、關閉)

1. WIFI的控制,主要是透過WifiManager來管理WIFI。

2.WifiManagerExample.java
package tw.nicky.WifiManagerExample;
import android.app.Activity;
import android.content.Context;
import android.net.wifi.WifiManager;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class WifiManagerExample extends Activity {
 private WifiManager wiFiManager;
 private Button turnOnWifiButn;
 private Button turnOffWifiButn;

 @Override
 public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.main);
  // 取得WifiManager
  wiFiManager = (WifiManager) this.getSystemService(Context.WIFI_SERVICE);
  turnOnWifiButn = (Button) findViewById(R.id.turnOnWifiButn);
  turnOffWifiButn = (Button) findViewById(R.id.turnOffWifiButn);

  // 開啟wifi
  turnOnWifiButn.setOnClickListener(new View.OnClickListener() {
   @Override
   public void onClick(View v) {
    //若wifi狀態為關閉則將它開啟
    if (!wiFiManager.isWifiEnabled()) {
     wiFiManager.setWifiEnabled(true);
    }
   }
  });

  // 關閉wifi
  turnOffWifiButn.setOnClickListener(new View.OnClickListener() {
   @Override
   public void onClick(View v) {
    //若wifi狀態為開啟則將它關閉
    if (wiFiManager.isWifiEnabled()) {
     wiFiManager.setWifiEnabled(false);
    }
   }
  });
 }
}

3. main.xml(Layout)
<?xml version="1.0" encoding="utf-8"?>
<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:text="開啟Wifi" 
android:id="@+id/turnOnWifiButn" 
android:layout_width="wrap_content" 
android:layout_height="wrap_content">
</Button>

<Button 
android:text="關閉Wifi" 
android:id="@+id/turnOffWifiButn" 
android:layout_width="wrap_content" 
android:layout_height="wrap_content">
</Button>
</LinearLayout>
4. AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="tw.nicky.WifiManagerExample"
      android:versionCode="1"
      android:versionName="1.0">
    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".WifiManagerExample"
                  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>
    <uses-permission android:name="android.permission.CHANGE_WIFI_STATE"></uses-permission>
    <uses-permission android:name="android.permission.WAKE_LOCK"></uses-permission>
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"></uses-permission>
</manifest> 


5. 執行畫面

2011年2月6日 星期日

Android - 錄音(MediaRecorder)

1. 要進行錄音需先取得錄音的權限,加上需將錄音檔寫到記憶卡,因此需在AndroidManifest.xml允許存取android.permission.RECORD_AUDIO及android.permission.WRITE_EXTERNAL_STORAGE這二個權限。

2.MediaRecorderExample.java
package tw.nicky;
import java.io.File;
import java.io.IOException;
import android.app.Activity;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.widget.Button;

public class MediaRecorderExample extends Activity {
 private Button recordButn;
 private Button stopButn;
 private MediaRecorder mediaRecorder = null;

 @Override
 public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.main);
  recordButn = (Button) findViewById(R.id.recordButn);
  stopButn = (Button) findViewById(R.id.stopButn);

  //錄音
  recordButn.setOnClickListener(new View.OnClickListener() {
   public void onClick(View v) {
    //設定錄音檔名
    String fileName = "record.amr";
    try {
     File SDCardpath = Environment.getExternalStorageDirectory();
                    File myDataPath = new File( SDCardpath.getAbsolutePath() + "/download" );
                    if( !myDataPath.exists() ) myDataPath.mkdirs();
     File recodeFile = new File(SDCardpath.getAbsolutePath() + "/download/"+fileName);
     
     mediaRecorder = new MediaRecorder();

     //設定音源
     mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
     //設定輸出檔案的格式
     mediaRecorder
       .setOutputFormat(MediaRecorder.OutputFormat.RAW_AMR);
     //設定編碼格式
     mediaRecorder
       .setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
     //設定錄音檔位置
     mediaRecorder
       .setOutputFile(recodeFile.getAbsolutePath());

     mediaRecorder.prepare();

     //開始錄音
     mediaRecorder.start();
    } catch (IOException e) {
     e.printStackTrace();
    }
   }
  });

  //停止錄音
  stopButn.setOnClickListener(new View.OnClickListener() {
   public void onClick(View v) {
    if(mediaRecorder != null) {
     mediaRecorder.stop();
     mediaRecorder.release();
     mediaRecorder = null;
    }
   }
  });

 }
}
3. main.xml(Layout)
<?xml version="1.0" encoding="utf-8"?>
<AbsoluteLayout
android:id="@+id/widget0"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android"
>
<Button
android:id="@+id/recordButn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="錄音"
android:layout_x="68px"
android:layout_y="44px"
>
</Button>
<Button
android:id="@+id/stopButn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="停止"
android:layout_x="170px"
android:layout_y="43px"
>
</Button>
</AbsoluteLayout>

4. AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="tw.nicky"
      android:versionCode="1"
      android:versionName="1.0">
    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".MediaRecorderExample"
                  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>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>
    <uses-permission android:name="android.permission.RECORD_AUDIO"></uses-permission>
</manifest> 


5. 執行畫面