For 1, ColorOS 3.0 and above, settings-other settings-auxiliary functions-press the power button to end the call, and just press the power button to hang up when opening, provided that the switch must be turned on);
2. For ColorOS and below, set-general-second "more"-auxiliary function-press the power button to end the call and turn it on;
3. non-ColorOS models: enter settings-general-auxiliary functions-press the power button to end the call switch.