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Heltec-Aaron-Lee / WiFi_Kit_series

Arduino source codes and toolchain for WiFi_Kit_series made by HelTecAutomation.
GNU Lesser General Public License v2.1
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unable to print WiFi.localIP().toString() to oled screen #2

Closed SmUrF3R5 closed 7 years ago

SmUrF3R5 commented 7 years ago

display.print(WiFi.localIP().toString(),3,0);

when i compile with this code get this error

/tmp/arduino_modified_sketch_829310/AdvancedWebServer.ino: In function 'void setup()': AdvancedWebServer:129: error: no matching function for call to 'OLED::print(String, int, int)' display.print(WiFi.localIP().toString(),3,0); ^ /tmp/arduino_modified_sketch_829310/AdvancedWebServer.ino:129:46: note: candidate is: In file included from /tmp/arduino_modified_sketch_829310/AdvancedWebServer.ino:35:0: /home/arduino-1.8.5/hardware/heltec/esp8266/libraries/OLED/OLED.h:32:8: note: void OLED::print(char, uint8_t, uint8_t) void print(char s, uint8_t r=0, uint8_t c=0); ^ /home/arduino-1.8.5/hardware/heltec/esp8266/libraries/OLED/OLED.h:32:8: note: no known conversion for argument 1 from 'String' to 'char*' exit status 1 no matching function for call to 'OLED::print(String, int, int)'

stelb commented 7 years ago

because print takes a pointer to char and toString returns an Object String.

display.print(WiFi.localIP().toString().c_str(),3,0);

should work

see also: https://forum.arduino.cc/index.php?topic=228884.msg3102705#msg3102705

SmUrF3R5 commented 7 years ago

hmm yeah sorry I am new to this platform and C. It seems i have to do this display.print((char*) WiFi.localIP().toString().c_str(),3,0);

saargrin commented 6 years ago

thanks @SmUrF3R5 ,that works