第三十三天SQLite（數據庫的增、刪、改、查）、讀取手機聯繫人、發送廣播

SQLite

MainActivity：

public class MainActivity extends Activity implements View.OnClickListener{
    private Button mButton;
    private Button mButtonInsert;
    private SQLiteDatabase database;
    private Button mButtonDelete;
    private Button mButtonUpdata;
    private Button mButtonSelect;
    private EditText mEdittextName;
    private EditText mEdittextPassword;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mButton= (Button) findViewById(R.id.button);
        mButtonInsert= (Button) findViewById(R.id.button_insert);
        mButtonDelete= (Button) findViewById(R.id.button_delete);
        mButtonUpdata= (Button) findViewById(R.id.button_updata);
        mButtonSelect= (Button) findViewById(R.id.button_select);
        mEdittextName= (EditText) findViewById(R.id.edittext_name);
        mEdittextPassword= (EditText) findViewById(R.id.edittext_password);
        mButton.setOnClickListener(this);
        mButtonInsert.setOnClickListener(this);
        mButtonDelete.setOnClickListener(this);
        mButtonUpdata.setOnClickListener(this);
        mButtonSelect.setOnClickListener(this);
        MySQLiteOpenHelper helper=new MySQLiteOpenHelper(getApplicationContext(),"MyDataBase");
        database=helper.getWritableDatabase();

    }

    @Override
    public void onClick(View view) {
        switch(view.getId()){
            case R.id.button:
               createDatabase();
                break;
            case R.id.button_insert:
                insertData();
                break;
            case R.id.button_delete:
                deleteData();
                break;
            case R.id.button_updata:
               updataData();
                break;
            case R.id.button_select:
                selectData();
                break;
            default:
                break;
        }
    }

    public void createDatabase(){
        Toast.makeText(MainActivity.this,"創建數據庫",Toast.LENGTH_LONG).show();
    }

    public void insertData(){
        ContentValues values=new ContentValues();
        values.put("nane",mEdittextName.getText().toString());
        values.put("password",mEdittextPassword.getText().toString());
        database.insert("user",null,values);
    }

    public void deleteData(){
        database.delete("user","nane=?",new String[]{"zhangsan"});
    }

    public void updataData(){
        ContentValues values1=new ContentValues();
        values1.put("password","abc");
        database.update("user",values1,"nane=?",new String[]{"zhangsan"});
    }
    public  void selectData(){
        Cursor cursor=database.rawQuery("select * from user",null);
        // Cursor cursor=database.query("user",null,null,null,null,null,"id desc","2");//查詢方式二
        cursor.moveToFirst();
        while(!cursor.isAfterLast()){
            String name=cursor.getString(cursor.getColumnIndex("nane"));
            String password=cursor.getString(cursor.getColumnIndex("password"));
            Log.d("cursor","用戶名： "+name+"  密碼： "+password);
            cursor.moveToNext();
        }
    }

MySQLiteOpenHelper:

public class MySQLiteOpenHelper extends SQLiteOpenHelper {

    public MySQLiteOpenHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) {
        super(context, name, factory, version);
    }

    public MySQLiteOpenHelper(Context context, String name){
        this(context, name,null,1);

    }

    @Override
    public void onCreate(SQLiteDatabase sqLiteDatabase) {
        sqLiteDatabase.execSQL("create table if not exists user(id integer primary key " +
                "autoincrement,nane varchar(20),password varchar(20))");

    }

    @Override
    public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {

    }
}

創建數據庫，插入數據：

---

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修改數據：

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刪除數據：

---

查詢數據：

查詢方式二：（id 降序，兩列）

 Cursor cursor=database.query("user",null,null,null,null,null,"id desc","1,2");1爲偏移量，2爲查詢的行數爲2行

讀取手機聯繫人

public class MainActivity extends Activity {
    private Button mButton;
    public ContentResolver mResolver;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mButton= (Button) findViewById(R.id.button);
        mButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                mResolver=getContentResolver();
                Uri uri= ContactsContract.CommonDataKinds.Phone.CONTENT_URI;
                Cursor cursor=mResolver.query(uri,new String[]{ContactsContract
                        .CommonDataKinds.Phone.NUMBER,ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME},null,null,null);
                cursor.moveToFirst();
                while(!cursor.isAfterLast()){
                    String[] names=cursor.getColumnNames();
                    StringBuffer buffer=new StringBuffer();
                    for(String name:names){
                        String value=cursor.getString(cursor.getColumnIndex(name));
                        buffer.append("字段名："+name+" 字段值："+value);
                    }
                    Log.d("聯繫人",""+buffer);
                    cursor.moveToNext();
                }
            }
        });
    }
}

權限設置：

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

廣播、鬧鐘

標準廣播（MyReceiver需要註冊：兩種方法）

MyReceiver:

public class MyReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        Toast.makeText(context,"接收到了廣播",Toast.LENGTH_SHORT).show();

    }
}

MainActivity:

public class MainActivity extends Activity implements View.OnClickListener{
    private Button mButtonSend;
    private MyReceiver mReceiver;
    private Button mButtonAlarm;
    private Button mButtonCancel;
    private AlarmManager mAlarmManager;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mAlarmManager= (AlarmManager) getSystemService(ALARM_SERVICE);
        mButtonSend= (Button) findViewById(R.id.button_send);
        mButtonAlarm= (Button) findViewById(R.id.button_alarm);
        mButtonCancel= (Button) findViewById(R.id.button_cancel);
        mButtonSend.setOnClickListener(this);
        mButtonAlarm.setOnClickListener(this);
        mButtonCancel.setOnClickListener(this);

        //動態註冊
        mReceiver=new MyReceiver();
        IntentFilter filter=new IntentFilter();
        filter.addAction("android.intent.action.MyReceiver");
        registerReceiver(mReceiver,filter);
    }
    @Override
    protected void onDestroy() {
        super.onDestroy();
        //取消註冊
        unregisterReceiver(mReceiver);
    }
    @Override
    public void onClick(View view) {
        switch (view.getId()){
            case R.id.button_send:
                sendBroadcast();
                break;
            case R.id.button_alarm:
                setAlarm();
                break;
            case R.id.button_cancel:
                cancelAlarm();
                break;
        }
    }

    public void sendBroadcast(){
        Intent intent=new Intent();
        intent.setAction("android.intent.action.MyReceiver");
        sendBroadcast(intent);
    }
    //設置鬧鐘
    public void setAlarm(){
        Intent intent=new Intent();  intent.setAction("android.intent.action.MyReceiver");
        PendingIntent pendingIntent=PendingIntent.getBroadcast(getApplicationContext(),0x13,intent,PendingIntent.FLAG_UPDATE_CURRENT);
        mAlarmManager.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(),3000,pendingIntent);//3000爲毫秒數，這裏鬧鐘按鈕的活動爲：每隔3秒發一次廣播
    }

//取消鬧鐘
    public void cancelAlarm(){
        Intent intent=new Intent();
        intent.setAction("android.intent.action.MyReceiver");
        PendingIntent pendingIntent=PendingIntent.getBroadcast(getApplicationContext(),0x13,intent,PendingIntent.FLAG_UPDATE_CURRENT);
        mAlarmManager.cancel(pendingIntent);
    }
}

MyReceiver除了可以在代碼中動態註冊外，還可在Mainifest中註冊:

<receiver android:name=".MyReceiver">
    <intent-filter>
          <action android:name="android.intent.action.MyReceiver"/>
    </intent-filter>
</receiver>

Service（啓動服務、取消服務）

MyService（需在Mainifest中註冊）

<service android:name=".MyService"></service>

public class MyService extends Service {
    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Log.d("service", "運行到onStartCommand");
        return super.onStartCommand(intent, flags, startId);
    }
    @Override
    public void onCreate() {
        Log.d("service", "運行到onCreate");
        super.onCreate();
    }
    @Override
    public void onDestroy() {
        Log.d("service", "運行到onDestroy");
        super.onDestroy();
    }
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }
}

MainActivity

public class MainActivity extends Activity implements View.OnClickListener{
    private Button mButtonStart;
    private Button mButtonStop;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mButtonStart= (Button) findViewById(R.id.button_start);
        mButtonStop= (Button) findViewById(R.id.button_stop);
        mButtonStart.setOnClickListener(this);
        mButtonStop.setOnClickListener(this);
    }
    @Override
    public void onClick(View view) {
        switch (view.getId()){
            case R.id.button_start:
                Intent intent=new Intent(getApplicationContext(),MyService.class);
                startService(intent);
                break;
            case R.id.button_stop:
                Intent intent1=new Intent(getApplicationContext(),MyService.class);
                stopService(intent1);
                break;
            default:
                break;
        }
    }
}

啓動服務：

取消服務：