context menu for display

src/main/java/org/solovyev/android/calculator/CalculatorDisplay.java

@@ -11,14 +11,21 @@ import android.text.Html;
 import android.util.AttributeSet;
 import android.util.Log;
 import jscl.math.Generic;
+import jscl.math.function.Constant;
+import jscl.math.function.IConstant;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.solovyev.android.calculator.jscl.JsclOperation;
 import org.solovyev.android.calculator.model.CalculatorEngine;
 import org.solovyev.android.calculator.model.CalculatorParseException;
 import org.solovyev.android.calculator.model.TextProcessor;
+import org.solovyev.android.view.AMenuBuilder;
+import org.solovyev.android.view.AMenuItem;
 import org.solovyev.android.view.AutoResizeTextView;
 
+import java.util.HashSet;
+import java.util.Set;
+
 /**
  * User: serso
  * Date: 9/17/11
@@ -26,6 +33,69 @@ import org.solovyev.android.view.AutoResizeTextView;
  */
 public class CalculatorDisplay extends AutoResizeTextView implements ICalculatorDisplay{
 
+	public static enum Menu implements AMenuItem<CalculatorDisplay> {
+		to_bin(0) {
+			@Override
+			public void doAction(@NotNull CalculatorDisplay data, @NotNull Context context) {
+				//To change body of implemented methods use File | Settings | File Templates.
+			}
+
+			@Override
+			protected boolean isItemVisibleFor(@NotNull Generic generic, @NotNull JsclOperation operation) {
+				return false;
+			}
+		},
+
+		plot(R.string.c_plot_graph) {
+			@Override
+			public void doAction(@NotNull CalculatorDisplay data, @NotNull Context context) {
+				//To change body of implemented methods use File | Settings | File Templates.
+			}
+
+			@Override
+			protected boolean isItemVisibleFor(@NotNull Generic generic, @NotNull JsclOperation operation) {
+				boolean result = false;
+
+				if (operation == JsclOperation.simplify) {
+					final Set<Constant> notSystemConstants = new HashSet<Constant>();
+					for (Constant constant : generic.getConstants()) {
+						IConstant var = CalculatorEngine.instance.getVarsRegistry().get(constant.getName());
+						if (var != null && !var.isSystem() && !var.isDefined()) {
+							notSystemConstants.add(constant);
+						}
+					}
+
+					if (notSystemConstants.size() == 1) {
+						result = true;
+					}
+				}
+
+				return result;
+			}
+		};
+
+		private final int captionId;
+
+		Menu(int captionId) {
+			this.captionId = captionId;
+		}
+
+		public final boolean isItemVisible(@NotNull CalculatorDisplay display) {
+			//noinspection ConstantConditions
+			return display.isValid() && display.getGenericResult() != null && isItemVisibleFor(display.getGenericResult(), display.getJsclOperation());
+		}
+
+		protected boolean isItemVisibleFor(@NotNull Generic generic, @NotNull JsclOperation operation) {
+			return true;
+		}
+
+		@NotNull
+		@Override
+		public String getCaption(@NotNull Context context) {
+			return context.getString(captionId);
+		}
+	}
+
 	private boolean valid = true;
 
 	@Nullable