android程式設計實例入門 -Sample改寫分享 (2014/10/30)

 

此範例為程式碼(08\Sample04)的改寫，利用一個LinearLayout、一個ImageView和一個TextView來實作GUI界面，利用利用IntentFilter建立監聽系統電池電力訊息的廣播資訊，而且將電池電力轉換成對應數值改變圖片的透明度，程式碼如下所示：

 

 

package com.jashsample;
import java.io.File;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
import java.util.Random;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnCompletionListener;
import android.media.MediaRecorder;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.SearchManager;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.DialogInterface;
import android.content.DialogInterface.OnKeyListener;
import android.content.Intent;
import android.content.IntentFilter;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Camera;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.Typeface;
import android.hardware.Camera.Size;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.speech.RecognizerIntent;
import android.speech.tts.TextToSpeech;
import android.speech.tts.TextToSpeech.OnInitListener;
import android.text.format.DateFormat;
import android.text.method.KeyListener;
import android.view.Display;
import android.view.Gravity;
import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.Surface;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnTouchListener;
import android.view.ViewGroup;
import android.view.WindowManager;
import android.view.animation.AlphaAnimation;
import android.view.animation.Animation;
import android.view.animation.AnimationSet;
import android.view.animation.RotateAnimation;
import android.view.animation.ScaleAnimation;
import android.view.animation.TranslateAnimation;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.CompoundButton.OnCheckedChangeListener;
import android.widget.EditText;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.Spinner;
import android.widget.TableLayout;
import android.widget.TableRow;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.ViewFlipper;
/*
 * 建立ImageView*1+TextView*1，利用IntentFilter建立監聽系統電池電力訊息的廣播資訊，而且將電池電力轉換成對應數值改變圖片的透明度。
 */
public class MainActivity extends Activity {
public static int SAMPLE_APP = 1;
TextView tv;
ImageView iv;
SampleBroadcastReceiver sb;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
LinearLayout ll = new LinearLayout(this);
ll.setOrientation(LinearLayout.VERTICAL);
setContentView(ll);
tv = new TextView(this);
iv = new ImageView(this);
Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.light);
iv.setImageBitmap(bmp);
ll.addView(tv);
ll.addView(iv);
sb = new SampleBroadcastReceiver();
}
protected void onResume()
{
super.onResume();
IntentFilter itf = new IntentFilter();
itf.addAction(Intent.ACTION_BATTERY_CHANGED);//建立監聽系統電池電力訊息的廣播資訊
registerReceiver(sb, itf);
}
protected void onPause()
{
super.onPause();
unregisterReceiver(sb);
}
class SampleBroadcastReceiver extends BroadcastReceiver
{
public void onReceive(Context cn, Intent it)//將電池電力轉換成對應數值改變圖片的透��度
{
String str = it.getAction();
if(str.equals(Intent.ACTION_BATTERY_CHANGED))
{
float level = it.getIntExtra("level", 0);
float scale = it.getIntExtra("scale", 1);
float b = level / scale;
tv.setText("電池殘量" + b *100 + "%");
AlphaAnimation anim = new AlphaAnimation(0, b);
anim.setDuration((long)(1000 / b));
anim.setRepeatMode(Animation.REVERSE);
anim.setRepeatCount(Animation.INFINITE);
iv.startAnimation(anim);
}
}
}
}