TextLCD_ostream.h

00001 #ifndef TEXTLCD_OSTREAM_H
00002 #define TEXTLCD_OSTREAM_H
00003 
00004 #include <ostream>
00005 #include <streambuf>
00006 
00007 /** ostream wrapper for TextLCD.
00008 LCDCLASS(TextLCD) need to have putc(),locate(),cls() function.
00009 @code
00010 #include "mbed.h"
00011 #include "TextLCD.h"
00012 #include "TextLCD_ostream.h"
00013  
00014 I2C i2c(p28,p27); // SDA, SCL
00015 TextLCD_I2C_N lcd(&i2c, ST7032_SA, TextLCD::LCD16x2, NC, TextLCD::ST7032_3V3);
00016 TextLCD_ostream<TextLCD_I2C_N> lcdstream(&lcd);
00017 
00018 int main() {
00019     using namespace std;
00020     lcd.setContrast(32);
00021     lcdstream.cls() << "Hello world" << endl << "LCD ostream";
00022 }
00023 @endcode
00024  */
00025 template <class LCDCLASS>
00026 class TextLCD_ostream : public std::ostream {
00027 public:
00028     /// @param p pointer to object of LCD class
00029     TextLCD_ostream (LCDCLASS *p)
00030       : std::ostream(&lcd_buf),lcdp(p),lcd_buf(p) {}
00031     /// access LCD object  
00032     LCDCLASS& lcd() {return *lcdp;}
00033     /// set cursor position.
00034     /// same as LCDCLASS::locate(), except return value type
00035     TextLCD_ostream& locate(int column, int row) {
00036         lcdp->locate(column,row);
00037         return *this;
00038     }
00039     /// clear screen
00040     /// same as LCDCLASS::cls(), except return value type
00041     TextLCD_ostream& cls(){
00042         lcdp->cls();
00043         return *this;
00044     }
00045 private:
00046     LCDCLASS* const lcdp;
00047     class TextLCD_streambuf : public std::streambuf {
00048     public:
00049         TextLCD_streambuf(LCDCLASS *p) : lcdp(p) {}
00050         virtual int_type overflow( int_type c = EOF ) {
00051             if( c != EOF ) lcdp->putc(c);
00052             return c;
00053         }
00054 
00055     private:
00056         LCDCLASS *lcdp;
00057     } lcd_buf;
00058 };
00059 
00060 #ifndef NOTextLCD_h
00061 //for compatibility to previous version
00062 #include "TextLCD.h"
00063 // specialized version
00064 typedef TextLCD_ostream<TextLCD_Base> lcd_ostream;
00065 #endif
00066 
00067 #endif