ImageView.setImageURI does not work for file URIs

The following code fails:

File f = ...

ImageView imageView = ...

imgView.setImageURI(Uri.fromFile(f));

Workaround:

imgView.setImageDrawable(Drawable.createFromPath(f.getAbsolutePath()));

Android Bluetooth scanning

Discovering Bluetooth devices in Android is fairly simple, there are a lot of examples on the internet. What not all of those examples show you, and what got me into trouble was the bold bit in the code snippet below: I didn't realise that BluetoothAdapter.getDefaultAdapter() will return null when the user turns Bluetooth of in the phone settings. That got me a nice NullPointerException ...

BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (bluetoothAdapter == null) {
    // bluetooth disabled/not available
}
else {
    context.registerReceiver(new BluetoothListener(), new IntentFilter(BluetoothDevice.ACTION_FOUND));

    bluetoothAdapter.startDiscovery();
}

private class BluetoothListener extends BroadcastReceiver {
    @Override
    public void onReceive(Context c, Intent intent) {
        BluetoothDevice rbd = (BluetoothDevice)intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);

        // ...
    }
}

Download an Android apk file from your site

This will probably never happen to you but, if you're in a similar situation as me, which is:

• you've got a website
• the website uses HTTPS and a self-signed certificate
• you try to download an APK file from that website directly onto your phone
  

Then you'll notice that the download starts but never completes, you'll get a perpetual "Waiting for data connection..." message. Took me a while to find out, but this is a known issue.

Install Android USB Driver for Windows to connect to a HTC Wildfire

I tried to install the Android USB Driver for Windows whilst my HTC Wildfire was connected to my PC. This failed. After some head-scratching and searching, I found out that I had to change the android_winusb.inf file (which is part of the installation files) so that it would recognize the device:

[Google.NTx86]
; HTC Dream
%SingleAdbInterface% = USB_Install, USB\VID_0BB4&PID_0C01
%CompositeAdbInterface% = USB_Install, USB\VID_0BB4&PID_0C02&MI_01
%SingleBootLoaderInterface% = USB_Install, USB\VID_0BB4&PID_0FFF
; HTC Magic
%CompositeAdbInterface% = USB_Install, USB\VID_0BB4&PID_0C03&MI_01
; HTC Wildfire
%SingleAdbInterface% = USB_Install, USB\VID_0BB4&PID_0C8B
%CompositeAdbInterface% = USB_Install, USB\VID_0BB4&PID_0C8B&MI_01
%SingleBootLoaderInterface% = USB_Install, USB\VID_0BB4&PID_0C8B

The bold lines are the ones I added: VID_0BB4 means Vendor ID = HTC, PID_0C8B means Product ID = Wildfire.