Detect power button long press

Go with this

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

And when you want to capture that event do this

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_POWER) {
        // this is method which detect press even of button
        event.startTracking(); // Needed to track long presses
        return true;
    }
    return super.onKeyDown(keyCode, event);
}

@Override
public boolean onKeyLongPress(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_POWER) {
        // Here we can detect long press of power button
        return true;
    }
    return super.onKeyLongPress(keyCode, event);
}

It can be done with broadcast receiver. see this answer


I see many answers trying to hookin to the powerbutton. However, wouldn't it be more easy to listen for the shutdown event? I'm not sure if this fits your need, but it seems like it.

Simply register a Broadcastreceiver to the following action(s):

<receiver android:name=".ShutdownReceiver">
    <intent-filter>
        <action android:name="android.intent.action.ACTION_SHUTDOWN" />
        <action android:name="android.intent.action.QUICKBOOT_POWEROFF" />
    </intent-filter>
</receiver>

Don't forget to add the following permission:

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


Sharing my method to do what you would like to achieve.

Basically, what it does is

  1. Asking for system permission to draw overlay (This is not a normal or vulnerable permission). This is not a user permission, so You should really know, what you are doing, by asking for it.

    public class MainActivity extends AppCompatActivity {
    
        public final static int REQUEST_CODE = 10101;
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            if (checkDrawOverlayPermission()) {
                startService(new Intent(this, PowerButtonService.class));
            }
        }
    
        public boolean checkDrawOverlayPermission() {
            if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
                return true;
            }
            if (!Settings.canDrawOverlays(this)) {
                /** if not construct intent to request permission */
                Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION,
                    Uri.parse("package:" + getPackageName()));
            /** request permission via start activity for result */
                startActivityForResult(intent, REQUEST_CODE);
                return false;
            } else {
                return true;
            }
        }
    
        @Override
        @TargetApi(Build.VERSION_CODES.M)
        protected void onActivityResult(int requestCode, int resultCode, Intent data) {
            if (requestCode == REQUEST_CODE) {
                if (Settings.canDrawOverlays(this)) {
                    startService(new Intent(this, PowerButtonService.class));
                }
            }
        }
    }
    
  2. Starting a service and adds a special view to WindowManager

  3. Waiting for an action inside View's onCloseSystemDialogs method.

    public class PowerButtonService extends Service {
    
        public PowerButtonService() {
    
        }
    
        @Override
        public void onCreate() {
            super.onCreate();
            LinearLayout mLinear = new LinearLayout(getApplicationContext()) {
    
                //home or recent button
                public void onCloseSystemDialogs(String reason) {
                    if ("globalactions".equals(reason)) {
                        Log.i("Key", "Long press on power button");
                    } else if ("homekey".equals(reason)) {
                        //home key pressed
                    } else if ("recentapps".equals(reason)) {
                        // recent apps button clicked
                    }
                }
    
                @Override
                public boolean dispatchKeyEvent(KeyEvent event) {
                    if (event.getKeyCode() == KeyEvent.KEYCODE_BACK
                        || event.getKeyCode() == KeyEvent.KEYCODE_VOLUME_UP
                        || event.getKeyCode() == KeyEvent.KEYCODE_VOLUME_DOWN
                        || event.getKeyCode() == KeyEvent.KEYCODE_CAMERA
                        || event.getKeyCode() == KeyEvent.KEYCODE_POWER) {
                        Log.i("Key", "keycode " + event.getKeyCode());
                    }
                    return super.dispatchKeyEvent(event);
                }
            };
    
            mLinear.setFocusable(true);
    
            View mView = LayoutInflater.from(this).inflate(R.layout.service_layout, mLinear);
            WindowManager wm = (WindowManager) getSystemService(WINDOW_SERVICE);
    
            //params
           final WindowManager.LayoutParams params;
    if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
    
        params = new WindowManager.LayoutParams(
                100,
                100,
                WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY,
                WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE
                        | WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN
                        | WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE,
                PixelFormat.TRANSLUCENT);
    } else {
        params = new WindowManager.LayoutParams(
                100,
                100,
                WindowManager.LayoutParams.TYPE_PHONE,
                WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL
                        | WindowManager.LayoutParams.FLAG_FULLSCREEN
                        | WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN
                        | WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON,
                PixelFormat.TRANSLUCENT);
    }
            params.gravity = Gravity.LEFT | Gravity.CENTER_VERTICAL;
            wm.addView(mView, params);
        }
    
        @Override
        public IBinder onBind(Intent intent) {
            return null;
        }
    }
    

Manifest:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="powerbuttonpress">

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

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>

        <service
            android:name=".PowerButtonService"
            android:enabled="true"
            android:exported="true">
        </service>

    </application>

</manifest>

service_layout:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

</LinearLayout>

This simple solution works:

    @Override
public boolean dispatchKeyEvent(KeyEvent event) {
    int keyPressed = event.getKeyCode();
    if(keyPressed==KeyEvent.KEYCODE_POWER){
        Log.d("###","Power button long click");
        Toast.makeText(MainActivity.this, "Clicked: "+keyPressed, Toast.LENGTH_SHORT).show();
        return true;}
    else
        return super.dispatchKeyEvent(event);
}

If you want to stop system pop-up, use the onWindowFocusChangedmethod specified in one of the answers below.

The output will show the toast with "Clicked:26" as attached below.enter image description here

Tags:

Events

Android