"First Line of Code" Notification + Receive, Intercept, Send SMS

 

13. Notification

There are relatively few scenarios in which notifications are created in activities, because generally we only need to use notifications when the program enters the background.

 

The getSystemService() method receives a string parameter to determine which service of the system to obtain 

 

The parameterized constructor of Notification accepts three parameters,

The first parameter is used to specify the icon of the notification

The second parameter is used to specify the ticker content of the notification. When the notification is just created, it will flash in the status bar of the system, which is a kind of instantaneous prompt information.

The third parameter is used to specify the time when the notification is created, in milliseconds. When the system status bar is pulled down, the time specified here will be displayed on the corresponding notification.

 

Notification's setLatestEventInfo() method can set a standard layout for the notification.

This method accepts four parameters, the first parameter is Context.

The second parameter is used to specify the title content of the notification, which can be seen by pulling down the system status bar.

The third parameter is used to specify the body content of the notification, which can be seen by pulling down the system status bar as well.

We don't need the fourth parameter yet, you can pass in null first

 

The notify() method accepts two parameters. The first parameter is the id. Make sure that the id specified for each notification is different.

 

 

Old spelling:

NotificationManager manager = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
Notification notification = new Notification(R.drawable.ic_launcher, "This is ticker text",
 System.currentTimeMillis());
notification.setLatestEventInfo(this, "This is content title","This is content text", null);
manager.notify(1, notification);

 

New spelling:

Notification.Builder builder1 = new Notification.Builder(MainActivity.this);
	builder1.setSmallIcon(R.drawable.advise2); //Set the icon
	builder1.setTicker("Show the second notification");
	builder1.setContentTitle("Notification"); //Set the title
	builder1.setContentText("Click to view details"); //Message content
	builder1.setWhen(System.currentTimeMillis()); //Send time
	builder1.setDefaults(Notification.DEFAULT_ALL);
//Set the default tone, vibration mode, light
	builder1.setAutoCancel(true);//The icon disappears after opening the program
	
	//jump
Intent intent =new Intent (MainActivity.this,NotificationActivity.class);
PendingIntent pendingIntent =PendingIntent.getActivity(MainActivity.this, 0, intent, 0);
builder1.setContentIntent(pendingIntent);
	
Notification notification1 = builder1.build();
notificationManager.notify(124, notification1); // Send notification via notification manager

 

Intent is more inclined to perform an action immediately, while PendingIntent is more inclined to perform an action at a suitable time . Therefore, PendingIntent can also be simply understood as a delayed Intent.

You can choose whether to use the getActivity() method, the getBroadcast() method, or the getService() method according to your needs.

 

The first parameter is still Context. The second parameter is generally not used, usually 0 can be passed in. The third parameter is an Intent object through which we can construct the "intent" of the PendingIntent. The fourth parameter is used to determine the behavior of the PendingIntent. There are four optional values: FLAG_ONE_SHOT, FLAG_NO_CREATE, FLAG_CANCEL_CURRENT and FLAG_UPDATE_CURRENT

 

Cancellation notice:

Receive notification activity NotificationActivity onCreate():

 

NotificationManager manager = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
manager.cancel(124);

 

The setLatestEventInfo method does not exist:

In systems lower than API Level 11, that is, Android 2.3.3 or lower, the setLatestEventInfo() function is the only implementation method.

notification.setLatestEventInfo(context, title, message, pendingIntent);          

 

In systems higher than API Level 11 and lower than API Level 16 (Android 4.1.2), Notification.Builder can be used to construct functions. But use getNotification() to make the notification come true. At this point, the Flags, icon and other attributes set in the notification in the previous version are invalid and must be set in the builder.

Notification.Builder builder = new Notification.Builder(context)  
            .setAutoCancel(true)  
            .setContentTitle("title")  
            .setContentText("describe")  
            .setContentIntent(pendingIntent)  
            .setSmallIcon(R.drawable.ic_launcher)  
            .setWhen(System.currentTimeMillis())  
            .setOngoing (true);  
	notification=builder.getNotification();

 

For versions higher than API Level 16, you can use the Builder and build() functions to facilitate the use of notifications.

 

Notification notification = new Notification.Builder(context)    
         .setAutoCancel(true)    
         .setContentTitle("title")    
         .setContentText("describe")    
         .setContentIntent(pendingIntent)    
         .setSmallIcon(R.drawable.ic_launcher)    
         .setWhen(System.currentTimeMillis())    
         .build();   

 

【接收短信】

声明权限：

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

 

当手机接收到一条短信的时候，系统会发出一条值为

android.provider.Telephony.SMS_RECEIVED 的广播，这条广播里携带着与短信相关的所有

数据。每个应用程序都可以在广播接收器里对它进行监听，收到广播时再从中解析出短信的内容即可

	class MessageReceiver extends BroadcastReceiver {
		@Override
		public void onReceive(Context context, Intent intent) {
			Bundle bundle = intent.getExtras();
			Object[] pdus = (Object[]) bundle.get("pdus"); // 提取短信消息
			SmsMessage[] messages = new SmsMessage[pdus.length];
			
			for (int i = 0; i < messages.length; i++) {
				messages[i] = SmsMessage.createFromPdu((byte[]) pdus[i]);
			}
			String address = messages[0].getOriginatingAddress(); // 获取发送方号码
			String fullMessage = "";
			for (SmsMessage message : messages) {
				fullMessage += message.getMessageBody(); 、
			}
			sender.setText(address);
			content.setText(fullMessage);
		}
	}
	
	//MainActivity中动态注册接收器广播：
	receiveFilter = new IntentFilter();
	receiveFilter.addAction("android.provider.Telephony.SMS_RECEIVED");
	messageReceiver = new MessageReceiver();
	registerReceiver(messageReceiver, receiveFilter);
	
	protected void onDestroy() {
		super.onDestroy();
		unregisterReceiver(messageReceiver);
	}

 

拦截短信：

你会发现在系统状态栏出现了一个通知图标，这个通知图标是由 Android自带的短信程序产生的。也就是说当短信到来时，不仅我们的程序会接收到这条短信，系统的短信程序同样也会收到。同样一条短信被重复接收两遍就会造成比较差的用户体验

 

系统发出的短信广播正是一条有序广播，所以可以拦截。

 

步骤：

一是提高 MessageReceiver 的优先级，让它能够先于系统短信程序接收到短信广播。

二是在 onReceive()方法中调用 abortBroadcast()方法

 

 

发送短信：

发送短信也是需要声明权限的

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

 

法1：

万能的intent能够帮我们做很多事，只要你有“意图”它就会满足你。

private void sendMessageViaSystem() {
        Uri uri = Uri.parse("smsto:"+etNumber.getText());
        Intent intent = new Intent(Intent.ACTION_VIEW,uri);
        intent.putExtra("sms_body",etMessage.getText().toString());
		//intent.setType("rnd");
        startActivity(intent);
    }

 

法2：

SmsManager smsManager = SmsManager.getDefault();
smsManager.sendTextMessage(to.getText().toString(), null, msgInput.getText().toString(), null, null);
	
	//sendTextMessage()方法接收五个参数，
	public void sendTextMessage(
            String destinationAddress, String scAddress, String text,
            PendingIntent sentIntent, PendingIntent deliveryIntent) 

 

其中第一个参数用于指定接收人的手机号码，

第三个参数用于指定短信的内容

第四个参数来对短信的发送状态进行监控

 

后两个参数是PendingIntent,我们要监听发送状态就要用到这两个参数。与这个两个PendingIntent联系的是两个Broadcast Receiver

 

 

发送后提示发送成功：

1、动态注册
	sendFilter = new IntentFilter();
	sendFilter.addAction("SENT_SMS_ACTION");
	sendStatusReceiver = new SendStatusReceiver();
	registerReceiver(sendStatusReceiver, sendFilter);
	
	2、发送短信
	SmsManager smsManager = SmsManager.getDefault();
	Intent sentIntent = new Intent("SENT_SMS_ACTION");
	PendingIntent pi = PendingIntent.getBroadcast(MainActivity.this, 0, sentIntent, 0);
	smsManager.sendTextMessage(to.getText().toString(), null,msgInput.getText().toString(), pi, null);
	
	3、广播接收器
	class SendStatusReceiver extends BroadcastReceiver {
		@Override
		public void onReceive(Context context, Intent intent) {
			if (getResultCode() == RESULT_OK) {
				// 短信发送成功
				Toast.makeText(context, "Send succeeded",Toast.LENGTH_LONG).show();
			} else {
				// 短信发送失败
				Toast.makeText(context, "Send failed",Toast.LENGTH_LONG).show();
			}
		}
	}

 

发送接收短信示例：

https://blog.csdn.net/lincyang/article/details/47686693

http://www.androidchina.net/3316.html

 

 

调用摄像头拍照

点击按钮后拍照，然后拍完后调用剪裁，剪裁完成后放入按钮下图片控件中。

 

调 用 Environment 的getExternalStorageDirectory()方法获取到的就是手机 SD 卡的根目录

涉及到了向 SD卡中写数据的操作,需要声明权限

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

@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		
		takePhoto = (Button) findViewById(R.id.take_photo);
		picture = (ImageView) findViewById(R.id.picture);
		
		takePhoto.setOnClickListener(new OnClickListener() {
			@Override
			public void onClick(View v) {
				// 创建File对象，用于存储拍照后的图片
				File outputImage = new File(Environment.getExternalStorageDirectory(), "tempImage.jpg");
				try {
					if (outputImage.exists()) {
						outputImage.delete();
					}
					outputImage.createNewFile();
				} catch (IOException e) {
					e.printStackTrace();
				}
				
				//调用摄像头拍照
				//将 File 对象转换成 Uri 对象,这个 Uri 对象标识着 output_image.jpg 这张图片的唯一地址
				imageUri = Uri.fromFile(outputImage);
				Intent intent = new Intent("android.media.action. IMAGE_CAPTURE");
				//指定图片的输出地址
				intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
				
				startActivityForResult(intent, TAKE_PHOTO); // 启动相机程序
			}
		});
	}
	
	@Override
	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
		switch (requestCode) {
		case TAKE_PHOTO:
			if (resultCode == RESULT_OK) {
				//这个 Intent 是用于对拍出的照片进行裁剪
				Intent intent = new Intent("com.android.camera.action.CROP");
				intent.setDataAndType(imageUri, "image/*");
				intent.putExtra("scale", true);
				intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
				
				 // 启动裁剪程序
				startActivityForResult(intent, CROP_PHOTO);
			}
			break;
		case CROP_PHOTO:
			if (resultCode == RESULT_OK) {
				try {
					Bitmap bitmap = BitmapFactory.decodeStream(getContentResolver().openInputStream(imageUri));
					picture.setImageBitmap(bitmap); // 将裁剪后的照片显示出来
				} catch (FileNotFoundException e) {
					e.printStackTrace();
				}
			}
			break;
		default:
			break;
		}
	}

 

从相册选取照片剪裁：

chooseFromAlbum.setOnClickListener(new OnClickListener() {
		@Override
		public void onClick(View v) {
			// 创建File对象，用于存储选择的照片
			File outputImage = new File(Environment.getExternalStorageDirectory(), "output_image.jpg");
			try {
				if (outputImage.exists()) {
					outputImage.delete();
				}
				outputImage.createNewFile();
			} catch (IOException e) {
				e.printStackTrace();
			}
			
			// 上面跟调用摄像头一样
			// 选取照片
			imageUri = Uri.fromFile(outputImage);
			Intent intent = new Intent("android.intent.action.GET_CONTENT");
			intent.setType("image/*");
			intent.putExtra("crop", true);
			intent.putExtra("scale", true);
			intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
			startActivityForResult(intent, CROP_PHOTO);
		}
	});

 

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