Click in HID mouse example

[SamV]

Dear Nordic Team,

I am using HID mouse example code in my nordic dk board.

I can able implemented fallowing logic in my code to do left , right and middle button click.

static void mouse_click_send(uint8_t x, uint8_t y, uint8_t z) { uint32_t err_code; uint8_t * buffer; if (m_in_boot_mode) return;

buffer[0] = x; // Left button (bit 0) pressed
buffer[1] = y; // Scroll value (-127, 128)
buffer[2] = z; // Sideways scroll value (-127, 128)

err_code = ble_hids_inp_rep_send(&m_hids,INPUT_REP_BUTTONS_INDEX, INPUT_REP_BUTTONS_LEN, buffer);
if ((err_code != NRF_SUCCESS) &&
    (err_code != NRF_ERROR_INVALID_STATE) &&
    (err_code != BLE_ERROR_NO_TX_BUFFERS) &&
    (err_code != BLE_ERROR_GATTS_SYS_ATTR_MISSING)
)
{
    APP_ERROR_CHECK(err_code);
}

}

mouse_click_send(1,0,0); // this is changing the screen in my android. mouse_click_send(2,0,0); // Nothing happen mouse_click_send(3,0,0); // Nothing happen

Could you tell me what this function will do exactly in android?.

I also need to do click in my android , so that i can open application.

Could you tell me what is data format i need to send?.

Kindly tell me, your help will be greatly appreciable.

Regards SamV

[Hung Bui]

Hi Sam,

Have you looked at this case ?

If you send mouse_click_send(1,0,0); would it act as a click in Android ?

I don't think Android main screen would handle right click, maybe in your app you can handle that, but I'm not 100% sure.

[SamV]

Yes , i checked that case , could you please let me know , how can i handle click in android.

or what is data need to send for click in android.

Or i also want to develop hid mouse application as absolute mouse ?.

Could you please tell me how to understand the report map data and characteristic?.

[Hung Bui]

Hi Sam, If you want to know how to handle mouse in Android you may have to look into this documentation.

A left mouse click in Android is pretty much the same as a touch on the screen.

Regarding HID report and how to understand, I found a good tutorial here. In that page you will find the link to the HID1_11.pdf spec defined by USB.org.

It's also explained by the answer from Jon Helge in the case I cited above.

[SamV]

I am confused, i went through that documents but not able to understand fully.

i just want to do click in my android by using existing ble hid mouse example.

kindly let me know how to do?.

[Hung Bui]

Hi SamV,

I found one bug with the code you provide. uint8_t * buffer; is not initialized before you use it. You should assign it to an array or do malloc. If you change the code to:

static void mouse_click_send(uint8_t x, uint8_t y, uint8_t z) 
	{ 
		uint32_t err_code; uint8_t buffer[3]; 
		if (m_in_boot_mode) return; 

    buffer[0] = x; // Left button (bit 0) pressed
		buffer[1] = y; // Scroll value (-127, 128)
		buffer[2] = z; // Sideways scroll value (-127, 128)

		err_code = ble_hids_inp_rep_send(&m_hids,INPUT_REP_BUTTONS_INDEX, INPUT_REP_BUTTONS_LEN, buffer);
		if ((err_code != NRF_SUCCESS) &&
				(err_code != NRF_ERROR_INVALID_STATE) &&
				(err_code != BLE_ERROR_NO_TX_BUFFERS) &&
				(err_code != BLE_ERROR_GATTS_SYS_ATTR_MISSING)
			)
		{
				APP_ERROR_CHECK(err_code);
		}
}

It should work.

To make a left click you call mouse_click_send(1,0,0); don't forget to release the key press by calling: mouse_click_send(0,0,0);