I have a very old Android 2.3.5 device (HTC Evo 4G) which has an HDMI cable connector. I am interested in using the wired HDMI connection to mirror the phone's screen or otherwise display images on an external monitor.
I have developed a simple slideshow application, but I don't know how to get the images to show on the external display.
When the HDMI cable is connected, the monitor 'knows' something is there, but the external monitor screen is blank. There used to be a tool on the play store (FullHDMI by TeamWin) that apparently allowed mirroring, but that tool is gone now. I thought that if that source code were available, I could see if there was device specific code or learn more about what needs to be done to enable external displays.
What needs to be done in the Android code so that the content is displayed on the external monitor when that external monitor is connected via an HDMI cable?