Usb Permissions Without Prompt

I have 2 activities within my app. Say FirstActivity and SecondActivity. FirstActivity is the MAIN and LAUNCHER activity. SecondActivity uses usb devices. I want the prompt for US

Solution 1:

Try "remove" intent filter <action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" /> from FirstActivity like in this question

Update

FirstActivity triggers on every USB_DEVICE_ATTACHED (even SecondActivity is running) because You set <action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" /> filter for it in AndroidManifest.xml file. So You should disable this filter when SecondActivity running. You can do this by that way:

1) add (e.g. AliasFirstActivity) in AndroidManifest.xml to your FirstActivity and move <action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" /> filter to alias description (You should remove <action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" />from FirstActivity description) like that:

<activity-aliasandroid:targetActivity=".FirstActivity"android:name=".AliasFirstActivity"android:label="@string/app_name"><intent-filter><actionandroid:name="android.intent.action.MAIN"/><categoryandroid:name="android.intent.category.LAUNCHER"/></intent-filter><intent-filter><actionandroid:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" /></intent-filter><meta-dataandroid:name="android.hardware.usb.action.USB_DEVICE_ATTACHED"android:resource="@xml/device_filter" /></activity-alias>

2) add this code to onCreate() (or to onResume()) of SecondActivity

PackageManagerpm= getApplicationContext().getPackageManager();
        ComponentNamecompName=newComponentName(getPackageName(), getPackageName() + ".AliasFirstActivity");
        pm.setComponentEnabledSetting(
                compName,
                PackageManager.COMPONENT_ENABLED_STATE_DISABLED,
                PackageManager.DONT_KILL_APP);

to suppress intent filter USB_DEVICE_ATTACHED for FirstActivity. You should have in SecondActivity something like that:

@OverrideprotectedvoidonCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_second);

        triggerReceiver = newTriggerReceiver();

        IntentFilterfilter=newIntentFilter();
        filter.addAction(UsbManager.ACTION_USB_DEVICE_ATTACHED);
        registerReceiver(triggerReceiver, filter);

        PackageManagerpm= getApplicationContext().getPackageManager();
        ComponentNamecompName=newComponentName(getPackageName(), getPackageName() + ".AliasFirstActivity");
        pm.setComponentEnabledSetting(
                compName,
                PackageManager.COMPONENT_ENABLED_STATE_DISABLED,
                PackageManager.DONT_KILL_APP);
    }

That should solve Your issue. 3) if it is needed, You can restore <action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" /> filter for FirstActivity in onDestroy() (or in onPause()) of SecondActivity by using this code:

PackageManagerpm= getApplicationContext().getPackageManager();
    ComponentNamecompName=newComponentName(getPackageName(), getPackageName() + ".AliasFirstActivity");
    pm.setComponentEnabledSetting(
            compName,
            PackageManager.COMPONENT_ENABLED_STATE_ENABLED,
            PackageManager.DONT_KILL_APP);

Solution 2:

But the problem is FirstActivity gets relaunched again when usb device is attached while SecondActivity is running. How do I avoid this?

This is not hard to answer. In your AndroidManifest.xml you literally declare that your FirstActivity should be launched when the event android.hardware.usb.action.USB_DEVICE_ATTACHED occurs.

If you want to handle this event in SecondActivity only, then you have to declare it in the manifest accordingly, for example:

<activityandroid:name=".FirstActivity"><intent-filter><actionandroid:name="android.intent.action.MAIN" /><categoryandroid:name="android.intent.category.LAUNCHER" /></intent-filter></activity><activityandroid:name=".SecondActivity"android:launchMode="singleTask"><intent-filter><actionandroid:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" /></intent-filter><meta-dataandroid:name="android.hardware.usb.action.USB_DEVICE_ATTACHED"android:resource="@xml/device_filter" /></activity>

Now, whenever your USB device is plugged in, SecondActivity will be launched only. If SecondActivity is already running, then it won't be launched again (or multiple times) because of the attribute android:launchMode="singleTask" specified for SecondActivity. You can read more about the different launch modes here if you're interested.

Since you declared in your manifest that SecondActivity should be launched when a USB device is plugged in, the Android system will ask you the following question:

After ticking the checkbox "Use by default for this USB device", it won't ask you again. Now, everytime you plug in the USB device, your SecondActivity will be launched and it will automatically receive the required USB permissions too.

Let me know if that answers your question.

Solution 3:

This answer might be helpful: USB device access pop-up suppression?

Code snippet:

publicclassUsbEventReceiverActivityextendsActivity
     {   
        publicstaticfinalStringACTION_USB_DEVICE_ATTACHED="com.example.ACTION_USB_DEVICE_ATTACHED";
        @OverrideprotectedvoidonCreate(Bundle savedInstanceState)
        {
            super.onCreate(savedInstanceState);
        }

    @OverrideprotectedvoidonResume()
    {
        super.onResume();

        Intentintent= getIntent();
        if (intent != null)
        {
            if (intent.getAction().equals(UsbManager.ACTION_USB_DEVICE_ATTACHED))
            {
                ParcelableusbDevice= intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);

                // Create a new intent and put the usb device in as an extraIntentbroadcastIntent=newIntent(ACTION_USB_DEVICE_ATTACHED);
                broadcastIntent.putExtra(UsbManager.EXTRA_DEVICE, usbDevice);

                // Broadcast this event so we can receive it
                sendBroadcast(broadcastIntent);
            }
        }

        // Close the activity
        finish();
    }
}