Detect Bluetooth state

Introduced from API Level 5, BluetoothAdapter lets you perform fundamental Bluetooth tasks, such as initiate device discovery, query a list of bonded (paired) devices, instantiate a BluetoothDevice using a known MAC address, and create a BluetoothServerSocket to listen for connection requests from other devices.

It's a exercise to detect Bluetooth state.



Modify AndroidManifest.xml to grant permission of "android.permission.BLUETOOTH".

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.exercise.AndroidBluetooth"
    android:versionCode="1"
    android:versionName="1.0">
  <uses-sdk android:minSdkVersion="7" />
  <uses-permission android:name="android.permission.BLUETOOTH"></uses-permission>

  <application android:icon="@drawable/icon" android:label="@string/app_name">
      <activity android:name=".AndroidBluetooth"
                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>
</manifest>

Main.xml

<?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"
  >
<TextView
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:text="@string/hello"
  />
<TextView
  android:id="@+id/bluetoothstate"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  />
</LinearLayout>

AndroidBluetooth.java

package com.exercise.AndroidBluetooth;

import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.os.Bundle;
import android.widget.TextView;

public class AndroidBluetooth extends Activity {
  /** Called when the activity is first created. */

TextView stateBluetooth;
BluetoothAdapter bluetoothAdapter;

  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.main);
    
      stateBluetooth = (TextView)findViewById(R.id.bluetoothstate);
      bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
    
      if (bluetoothAdapter == null){
       stateBluetooth.setText("Bluetooth NOT support");
      }else{
       if (bluetoothAdapter.isEnabled()){
        if(bluetoothAdapter.isDiscovering()){
         stateBluetooth.setText("Bluetooth is currently in device discovery process.");
        }else{
         stateBluetooth.setText("Bluetooth is Enabled.");
        }
       }else{
        stateBluetooth.setText("Bluetooth is NOT Enabled!");
       }
      }
    
    
    
  }
}

Download the files.

next:
- Turn-On BlueTooth using intent of BluetoothAdapter.ACTION_REQUEST_ENABLE