Android Studio - Bluetooth 掃描設備程式（三十九）

Android Studio - Bluetooth 掃描設備程式（三十九）：

當設定 Bluetooth 許可權限完成後，便可以開始編寫程式，首先是要設定手機藍牙，然後啟動手機藍牙，再掃描周邊的藍牙設備，顯示藍牙設備資料。

Android Studio Bluetooth 掃描設備程式

操作系統：Windows 7 64-bit 版本
開發環境：Android Studio 4.0.1 版本
原程式：C:\Development\Development_Android\Android_Project\DIY-Android-010-01A Bluetooth Scan
程式：C:\Development\Development_Android\Android_Project\DIY-Android-010-01A Bluetooth Scan

Bluetooth 掃描設備程式編程步驟：

• 設定 Bluetooth 許可權限後
• 設定手機藍牙
• 啟動手機藍牙
• 掃描周邊的藍牙設備
• 顯示周邊藍牙設備資料

MainActivity.java：

import androidx.appcompat.app.AppCompatActivity; import android.os.Bundle; import android.widget.ArrayAdapter; import android.widget.Button; import android.widget.ListView; import android.widget.TextView; import android.widget.Toast; import android.content.Intent; import android.content.Context; import android.content.IntentFilter; import android.view.View;   // Bluetooth API import android.bluetooth.BluetoothAdapter; import android.bluetooth.BluetoothDevice; import android.content.BroadcastReceiver;   public class MainActivity extends AppCompatActivity {       // GUI Components     private TextView mtv_status;     private Button mbtn_on;     private Button mbtn_Scan;     private ListView mlv_device;       private BluetoothAdapter mBTAdapter;     private ArrayAdapter<String> mBTArrayAdapter;       private final static int REQUEST_ENABLE_BT = 1; // used to identify adding bluetooth names       @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);           mbtn_on = (Button) findViewById(R.id.btn_on);         mbtn_Scan = (Button) findViewById(R.id.btn_scan);         mlv_device = (ListView)findViewById(R.id.lv_device);           mBTArrayAdapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1);         mBTAdapter = BluetoothAdapter.getDefaultAdapter(); // get a handle on the bluetooth radio           mlv_device.setAdapter(mBTArrayAdapter); // assign model to view           mbtn_on.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                 bluetoothOn();             }         });           mbtn_Scan.setOnClickListener(new View.OnClickListener(){             @Override             public void onClick(View v){                 scan();             }         });     }       // Bluetooth Turn ON     private void bluetoothOn(){         if (!mBTAdapter.isEnabled()) {             Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);             startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);             //mBluetoothStatus.setText("Bluetooth Enabled");             Toast.makeText(getApplicationContext(),"Bluetooth Turned On",Toast.LENGTH_SHORT).show();         }         else{             Toast.makeText(getApplicationContext(),"Bluetooth is Already On", Toast.LENGTH_SHORT).show();         }     }         // Discovery Bluetooth Device     private void scan(){         // Check if the device is already discovering         if(mBTAdapter.isDiscovering()){             mBTAdapter.cancelDiscovery();             Toast.makeText(getApplicationContext(),"Scan Stopped",Toast.LENGTH_SHORT).show();         }         else{             if(mBTAdapter.isEnabled()) {                 mBTArrayAdapter.clear(); // clear items                 mBTAdapter.startDiscovery();                 Toast.makeText(getApplicationContext(), "Discovery Started", Toast.LENGTH_SHORT).show();                 registerReceiver(blReceiver, new IntentFilter(BluetoothDevice.ACTION_FOUND));             }             else{                 Toast.makeText(getApplicationContext(), "Bluetooth Not On", Toast.LENGTH_SHORT).show();             }         }     }       final BroadcastReceiver blReceiver = new BroadcastReceiver() {         @Override         public void onReceive(Context context, Intent intent) {             String action = intent.getAction();             if(BluetoothDevice.ACTION_FOUND.equals(action)){                 BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);                 mBTArrayAdapter.add(device.getName() + "\n" + device.getAddress());                 mBTArrayAdapter.notifyDataSetChanged();             }         }       }; }

activity_main.xml：

<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"     xmlns:app="http://schemas.android.com/apk/res-auto"     xmlns:tools="http://schemas.android.com/tools"     android:layout_width="match_parent"     android:layout_height="match_parent"     tools:context=".MainActivity">       <TextView         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:layout_alignParentStart="true"         android:layout_alignParentLeft="true"         android:layout_alignParentTop="true"         android:layout_marginStart="132dp"         android:layout_marginLeft="132dp"         android:layout_marginTop="16dp"         android:text="Hello Bluetooth!" />       <Button         android:id="@+id/btn_on"         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:layout_alignParentStart="true"         android:layout_alignParentLeft="true"         android:layout_alignParentTop="true"         android:layout_marginStart="12dp"         android:layout_marginLeft="12dp"         android:layout_marginTop="40dp"         android:text="ON" />       <Button         android:id="@+id/btn_scan"         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:layout_below="@+id/btn_on"         android:layout_alignParentStart="true"         android:layout_alignParentLeft="true"         android:layout_marginStart="12dp"         android:layout_marginLeft="12dp"         android:layout_marginTop="11dp"         android:text="Scan" />       <ListView         android:id="@+id/lv_device"         android:layout_width="384dp"         android:layout_height="548dp"         android:layout_below="@+id/btn_scan"         android:layout_alignParentBottom="true"         android:layout_centerHorizontal="true"         android:layout_marginStart="16dp"         android:layout_marginLeft="16dp"         android:layout_marginTop="5dp" /> </RelativeLayout>

Android Studio Bluetooth 掃描設備程式

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