Simple calculator for OC implementation

<P> // Note: only simple addition, subtraction, multiplication, division, and continuous operation are allowed. </P> <p> # define kbutton_color [uicolor cyancolor] // defines the background color macro of the key, easy to change color </P> @ interface yjappdelegate () {uiview * _ containter; uibutton * _ numberbutton; uilabel * _ label; cgfloat num1, operators, result, digital; nsmutablestring * _ string; nsstring * _ symboltext;} @ end <PRE name = "code" class = "objc"> _ containter = [[uiview alloc] initwithframe: cgrectmake (0, 0,320,568)]; _ containter. backgroundcolor = [uicolor graycolor]; [self. window addsubview: _ containter]; [_ containter release]; // set the number nsarray * array = [nsarray arraywithobjects: @ "1", @ "2", @ "3 ", @ "4", @ "5", @ "6", @ "7", @ "8", @ "9", nil]; int n = 0; for (INT I = 0; I <3; I ++) {for (Int J = 0; j <3; j ++) {_ numberbutton = [uibutton buttonwithtype: uibuttontypesystem]; _ numberbutton. frame = cgrectmake (J * 80), 180 + (I * 80), 78, 78); [_ numberbutton settitle: [array objectatindex: N ++] forstate: uicontrolstatenormal]; _ numberbutton. backgroundcolor = kbutton_color; _ numberbutton. titlelabel. font = [uifont systemfontofsize: 22]; _ numberbutton. layer. cornerradius = 30; [_ numberbutton addtarget: Self action: @ selector (number :) forcontrolevents: uicontroleventtouchupinside]; [_ containter addsubview: _ numberbutton];} // set the return key uibutton * backbutton = [uibutton buttonwithtype: uibuttontypesystem]; backbutton. frame = cgrectmake (240,180, 78, 78); [backbutton settitle: @ "back" forstate: uicontrolstatenormal]; backbutton. backgroundcolor = kbutton_color; backbutton. titlelabel. font = [uifont systemfontofsize: 22]; backbutton. layer. cornerradius = 30; [backbutton addtarget: Self action: @ selector (Back :) forcontrolevents: uicontroleventtouchupinside]; [_ containter addsubview: backbutton]; // set the symbol key nsarray * array2 = [nsarray arraywithobjects: @ "+", @ "-", @ "*", @ "/", nil]; for (INT I = 0; I <4; I ++) {uibutton * symbolbutton = [uibutton buttonwithtype: uibuttontypesystem]; symbolbutton. frame = cgrectmake (240,260 + (I * 80), 78, 78); [symbolbutton settitle: [array2 objectatindex: I] forstate: uicontrolstatenormal]; symbolbutton. backgroundcolor = kbutton_color; symbolbutton. titlelabel. font = [uifont systemfontofsize: 22]; symbolbutton. layer. cornerradius = 30; [symbolbutton addtarget: Self action: @ selector (symbol :) forcontrolevents: uicontroleventtouchupinside]; [_ containter addsubview: symbolbutton];} // set 0 and. nsarray * array3 = [nsarray arraywithobjects: @ "0 ",@". ", nil]; for (INT I = 0; I <2; I ++) {uibutton * button = [uibutton buttonwithtype: uibuttontypesystem]; button. frame = cgrectmake (80 + (I * 80), 420, 78, 78); button. backgroundcolor = kbutton_color; button. titlelabel. font = [uifont systemfontofsize: 22]; button. layer. cornerradius = 30; [Button settitle: [array3 objectatindex: I] forstate: uicontrolstatenormal]; [Button addtarget: Self action: @ selector (Button :) forcontrolevents: uicontroleventtouchupinside]; [_ containter addsubview: button];} // set uibutton * acbutton = [uibutton buttonwithtype: uibuttontypesystem]; acbutton. frame = cgrectmake (0,420, 78, 78); acbutton. backgroundcolor = kbutton_color; acbutton. layer. cornerradius = 30; acbutton. titlelabel. font = [uifont systemfontofsize: 22]; [acbutton settitle: @ "AC" forstate: uicontrolstatenormal]; [acbutton addtarget: Self action: @ selector (AC :) forcontrolevents: uicontroleventtouchupinside]; [_ containter addsubview: acbutton]; // set the uibutton * symbol button = [uibutton buttonwithtype: uibuttontypesystem]; symbol button. frame = cgrectmake (0,500,240, 68); reset button. backgroundcolor = kbutton_color; Specify button. titlelabel. font = [uifont systemfontofsize: 22]; then button. layer. cornerradius = 30; [using button settitle: @ "=" forstate: uicontrolstatenormal]; [using button addtarget: Self action: @ selector (equal :) forcontrolevents: uicontroleventtouchupinside]; [_ containter addsubview: export button]; // set the display window _ label = [[uilabel alloc] initwithframe: cgrectmake (10, 80,300, 60)]; _ label. backgroundcolor = [uicolor whitecolor]; _ label. textcolor = [uicolor bluecolor]; _ label. layer. cornerradius = 3; _ label. textalignment = nstextalignmentleft; _ label. font = [uifont systemfontofsize: 20]; [_ containter addsubview: _ label]; [_ label release]; // set the displayed text to string _ string = [[nsmutablestring alloc] init];

// Configure the number key trigger-(void) number :( uibutton *) number {[_ string appendstring: [number currenttitle]; _ label. TEXT = [nsstring stringwithstring: _ string]; num1 = [_ label. text doublevalue];} // configure 0 and. -(void) button :( uibutton *) button {[_ string appendstring: [Button currenttitle]; _ label. TEXT = [nsstring stringwithstring: _ string]; num1 = [_ label. text doublevalue];} // configure the trigger of the operator key-(void) symbol :( uibutton *) symbol {[_ St Ring setstring: @ ""]; [_ string appendstring: [Symbol currenttitle]; _ label. TEXT = [nsstring stringwithstring: _ string]; If ([_ string hasprefix: @ "+"]) {digital = num1; // store the operators = 1 number entered for the first time; // store the input operator [_ string setstring: @ ""]; // clear the interface after the input operator} else if ([_ string hasprefix: @ "-"]) {digital = num1; operators = 2; // [_ string setstring: @ ""];} else if ([_ string hasprefix: @ "*"]) {digital = num1; operato Rs = 3; [_ string setstring: @ ""];} else if ([_ string hassuffix: @ "/"]) {digital = num1; operators = 4; [_ string setstring: @ ""] ;}// configure the equal key trigger-(void) equal :( uibutton *) equal {If (operators = 1) {result = digital + [_ label. text doublevalue]; // [_ label. text doublevalue] is the second input number _ label. TEXT = [nsstring stringwithformat: @ "% G", result]; // display the result [_ string setstring: @ ""]; // clear the result} else if (operators = 2 ){ Result = digital-(-[_ label. text doublevalue]); _ label. TEXT = [nsstring stringwithformat: @ "% G", result]; [_ string setstring: @ ""];} else if (operators = 3) {result = digital * [_ label. text doublevalue]; _ label. TEXT = [nsstring stringwithformat: @ "% G", result]; [_ string setstring: @ ""];} else if (operators = 4) {result = digital/[_ label. text doublevalue]; _ label. TEXT = [nsstring stringwithfo Rmat: @ "% G", result]; [_ string setstring: @ ""] ;}// configure the trigger of the zeroth key-(void) AC :( uibutton *) AC {[_ string setstring: @ ""]; Result = 0; operators = 0; _ label. TEXT = @ "0";} // configure the trigger of the Return key-(void) Back :( uibutton *) back {If (! [_ Label. text isequal: @ ""]) {[_ string deletecharactersinrange: nsmakerange ([_ String Length]-1, 1)]; // Delete the last character _ label. TEXT = [nsstring stringwithstring: _ string]; // display the deleted string num1 = [_ label. text floatvalue]; // receives the deleted number }}