android-calculatorpp-114: "Calculator while typing" option is ignored

Fixes#114

android-app/src/main/java/org/solovyev/android/calculator/AndroidCalculator.java

@@ -104,6 +104,11 @@ public class AndroidCalculator implements Calculator, CalculatorEventListener, S
 		return calculator.evaluate(operation, expression, sequenceId);
 	}
 
+	@Override
+	public boolean isCalculateOnFly() {
+		return calculator.isCalculateOnFly();
+	}
+
 	@Override
 	public boolean isConversionPossible(@Nonnull Generic generic, @Nonnull NumeralBase from, @Nonnull NumeralBase to) {
 		return calculator.isConversionPossible(generic, from, to);

core/src/main/java/org/solovyev/android/calculator/Calculator.java

@@ -64,6 +64,8 @@ public interface Calculator extends CalculatorEventContainer, HistoryControl<Cal
 								 @Nonnull String expression,
 								 @Nonnull Long sequenceId);
 
+	boolean isCalculateOnFly();
+
 	/*
 	**********************************************************************
 	*

core/src/main/java/org/solovyev/android/calculator/CalculatorImpl.java

@@ -211,6 +211,11 @@ public class CalculatorImpl implements Calculator, CalculatorEventListener {
 		this.calculateOnFly = calculateOnFly;
 	}
 
+	@Override
+	public boolean isCalculateOnFly() {
+		return calculateOnFly;
+	}
+
 	@Nonnull
 	private CalculatorConversionEventData newConversionEventData(@Nonnull Long sequenceId,
 																 @Nonnull Generic value,

core/src/main/java/org/solovyev/android/calculator/CalculatorSpecialButton.java

@@ -102,6 +102,13 @@ public enum CalculatorSpecialButton {
 	equals("=") {
 		@Override
 		public void onClick(@Nonnull CalculatorKeyboard keyboard) {
+			final Calculator calculator = Locator.getInstance().getCalculator();
+			if (!calculator.isCalculateOnFly()) {
+				// no automatic calculations are => equals button must be used to calculate
+				calculator.evaluate();
+				return;
+			}
+
 			final CalculatorDisplayViewState displayViewState = Locator.getInstance().getDisplay().getViewState();
 			if (displayViewState.isValid()) {
 				final CharSequence text = displayViewState.getText();