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If the input device has any keys that are mapped to KEYCODE_DPAD_UP, KEYCODE_DPAD_DOWN, KEYCODE_DPAD_LEFT, KEYCODE_DPAD_RIGHT, and KEYCODE_DPAD_CENTER (all must be present), then the device is considered to have a directional keypad.
Legacy Unsupported Keys
These mappings appeared in previous versions of Android but were inconsistent with HID or used non-standard Linux key codes. They are no longer supported.
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LKC Linux Key Code Name Version AKC Android Key Code Name Notes 0x00e8 KEY_CENTER 1.6 0x0017 KEYCODE_DPAD_CENTER 4