jaroslav@141:
jaroslav@141:
jaroslav@141:
jaroslav@141:
jaroslav@141:
jaroslav@141: Simple Calculator in HTML5 and Java
jtulach@197:
jtulach@197:
jtulach@197:
jaroslav@141:
jaroslav@198: Java and HTML5 - Together at Last!
jaroslav@141:
jaroslav@141:
jaroslav@141:
jtulach@197:
jtulach@197:
jaroslav@198:
jaroslav@198: package org.apidesign.bck2brwsr.mavenhtml;
jaroslav@198:
jaroslav@198: import org.apidesign.bck2brwsr.htmlpage.api.OnClick;
jaroslav@198: import org.apidesign.bck2brwsr.htmlpage.api.Page;
jaroslav@198:
jaroslav@198: annotation processors
jaroslav@198:
jaroslav@198:
jaroslav@198:
jaroslav@198: @author <jaroslav.tulach@apidesign.org>
jaroslav@198:
jaroslav@198: @Page(xhtml="Calculator.xhtml")
jaroslav@198: public class App {
jaroslav@198: private static double memory;
jaroslav@198: private static String operation;
jaroslav@198:
jaroslav@198: @OnClick(id="clear")
jaroslav@198: static void clear() {
jaroslav@198: memory = 0;
jaroslav@198: operation = null;
jaroslav@198: Calculator.DISPLAY.setValue("0");
jaroslav@198: }
jaroslav@198:
jaroslav@198: @OnClick(id= { "plus", "minus", "mul", "div" })
jaroslav@198: static void applyOp(String op) {
jaroslav@198: memory = getValue();
jaroslav@198: operation = op;
jaroslav@198: Calculator.DISPLAY.setValue("0");
jaroslav@198: }
jaroslav@198:
jaroslav@198: @OnClick(id="result")
jaroslav@198: static void computeTheValue() {
jaroslav@198: switch (operation) {
jaroslav@198: case "plus": setValue(memory + getValue()); break;
jaroslav@198: case "minus": setValue(memory - getValue()); break;
jaroslav@198: case "mul": setValue(memory * getValue()); break;
jaroslav@198: case "div": setValue(memory / getValue()); break;
jaroslav@198: default: throw new IllegalStateException(operation);
jaroslav@198: }
jaroslav@198: }
jaroslav@198:
jaroslav@198: @OnClick(id={"n0", "n1", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9"})
jaroslav@198: static void addDigit(String digit) {
jaroslav@198: digit = digit.substring(1);
jaroslav@198: String v = Calculator.DISPLAY.getValue();
jaroslav@198: if (getValue() == 0.0) {
jaroslav@198: Calculator.DISPLAY.setValue(digit);
jaroslav@198: } else {
jaroslav@198: Calculator.DISPLAY.setValue(v + digit);
jaroslav@198: }
jaroslav@198: }
jaroslav@198:
jaroslav@198: private static void setValue(double v) {
jaroslav@198: StringBuilder sb = new StringBuilder();
jaroslav@198: sb.append(v);
jaroslav@198: Calculator.DISPLAY.setValue(sb.toString());
jaroslav@198: }
jaroslav@198:
jaroslav@198: private static double getValue() {
jaroslav@198: try {
jaroslav@198: return Double.parseDouble(Calculator.DISPLAY.getValue());
jaroslav@198: } catch (NumberFormatException ex) {
jaroslav@198: Calculator.DISPLAY.setValue("err");
jaroslav@198: return 0.0;
jaroslav@198: }
jaroslav@198: }
jaroslav@198: }
jaroslav@198:
jaroslav@198:
jaroslav@141:
jaroslav@141: