functions

calculatorpp-core/src/main/java/org/solovyev/android/calculator/CalculatorFunctionsMathRegistry.java

@@ -16,6 +16,7 @@ import org.solovyev.android.calculator.model.MathEntityBuilder;
 import org.solovyev.common.JBuilder;
 import org.solovyev.common.math.MathRegistry;
 
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.Map;
@@ -96,7 +97,7 @@ public class CalculatorFunctionsMathRegistry extends AbstractCalculatorMathRegis
 			final AFunction result = new AFunction();
 			result.setName(entity.getName());
 			result.setContent(((CustomFunction) entity).getContent());
-			result.setParameterNames(((CustomFunction) entity).getParameterNames());
+			result.setParameterNames(new ArrayList<String>(((CustomFunction) entity).getParameterNames()));
 			return result;
 		} else {
 			return null;

calculatorpp-core/src/main/java/org/solovyev/android/calculator/ToJsclTextProcessor.java

@@ -72,12 +72,6 @@ public class ToJsclTextProcessor implements TextProcessor<PreparedExpression, St
 				}
 			}
 
-			if (mathTypeBefore != null &&
-					(mathTypeBefore.getMathType() == MathType.function || mathTypeBefore.getMathType() == MathType.operator) &&
-						CollectionsUtils.find(MathType.openGroupSymbols, startsWithFinder) != null) {
-                throw new CalculatorParseException(i, s, new CalculatorMessage(CalculatorMessages.msg_005, MessageType.error, mathTypeBefore.getMatch()));
-			}
-
 			i = mathTypeResult.processToJscl(result, i);
 		}
 		return result;

calculatorpp-core/src/main/java/org/solovyev/android/calculator/model/AFunction.java

@@ -6,16 +6,18 @@
 
 package org.solovyev.android.calculator.model;
 
-import jscl.math.function.IConstant;
 import jscl.math.function.IFunction;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.simpleframework.xml.Element;
+import org.simpleframework.xml.ElementList;
 import org.simpleframework.xml.Root;
 import org.simpleframework.xml.Transient;
 import org.solovyev.android.calculator.MathPersistenceEntity;
 import org.solovyev.common.math.MathEntity;
+import org.solovyev.common.text.StringUtils;
 
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 
@@ -25,7 +27,7 @@ import java.util.List;
  * Time: 5:25 PM
  */
 
-@Root
+@Root(name = "function")
 public class AFunction implements IFunction, MathPersistenceEntity {
 
 	/*
@@ -42,20 +44,20 @@ public class AFunction implements IFunction, MathPersistenceEntity {
 	@NotNull
 	private String name;
 
-	@Element
+	@Element(name = "body")
 	@NotNull
 	private String content;
 
-	@Element(required = false)
+	@ElementList
 	@NotNull
-	private List<String> parameterNames = Collections.emptyList();
+	private List<String> parameterNames = new ArrayList<String>();
 
 	@Element
 	private boolean system;
 
 	@Element(required = false)
-	@Nullable
+	@NotNull
-	private String description;
+	private String description = "";
 
 	/*
 	**********************************************************************
@@ -86,7 +88,7 @@ public class AFunction implements IFunction, MathPersistenceEntity {
 			final IFunction that = ((IFunction) mathEntity);
 			this.name = that.getName();
 			this.content = that.getContent();
-			this.description = this.getContent();
+			this.description = StringUtils.getNotEmpty(this.getDescription(), "");
 			this.system = that.isSystem();
 			if (that.isIdDefined()) {
 				this.id = that.getId();
@@ -104,7 +106,7 @@ public class AFunction implements IFunction, MathPersistenceEntity {
 	/*
 	**********************************************************************
 	*
-	*                           GETTERS/SEETTERS
+	*                           GETTERS/SETTERS
 	*
 	**********************************************************************
 	*/
@@ -144,7 +146,7 @@ public class AFunction implements IFunction, MathPersistenceEntity {
 		return content;
 	}
 
-	@Nullable
+	@NotNull
     @Override
 	public String getDescription() {
 		return this.description;
@@ -201,28 +203,14 @@ public class AFunction implements IFunction, MathPersistenceEntity {
 			this.id = function.getId();
 		}
 
-		public Builder(@NotNull IConstant function) {
+        public Builder(@NotNull String name,
-			this.name = function.getName();
+                       @NotNull String value,
-
+                       @NotNull List<String> parameterNames) {
-			this.value = function.getValue();
-
-			this.system = function.isSystem();
-			this.description = function.getDescription();
-			if (function.isIdDefined()) {
-				this.id = function.getId();
-			}
-		}
-
-		public Builder(@NotNull String name, @NotNull Double value) {
-			this(name, String.valueOf(value));
-		}
-
-		public Builder(@NotNull String name, @Nullable String value) {
             this.name = name;
             this.value = value;
+            this.parameterNames = parameterNames;
         }
 
-
         @NotNull
 		public Builder setName(@NotNull String name) {
 			this.name = name;
@@ -262,8 +250,8 @@ public class AFunction implements IFunction, MathPersistenceEntity {
 			result.name = name;
 			result.content = value;
 			result.system = system;
-			result.description = description;
+			result.description = StringUtils.getNotEmpty(description, "");
-			result.parameterNames = parameterNames;
+			result.parameterNames = new ArrayList<String>(parameterNames);
 
 			return result;
 		}

calculatorpp-core/src/test/java/org/solovyev/android/calculator/model/FunctionsTest.java

@@ -0,0 +1,155 @@
+package org.solovyev.android.calculator.model;
+
+import jscl.util.ExpressionGenerator;
+import org.hamcrest.BaseMatcher;
+import org.hamcrest.Description;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.junit.Assert;
+import org.junit.Test;
+import org.simpleframework.xml.Serializer;
+import org.simpleframework.xml.core.Persister;
+import org.solovyev.common.equals.CollectionEqualizer;
+import org.solovyev.common.equals.EqualsUtils;
+import org.solovyev.common.text.StringUtils;
+
+import java.io.StringWriter;
+import java.util.*;
+
+/**
+ * User: serso
+ * Date: 11/14/12
+ * Time: 8:06 PM
+ */
+public class FunctionsTest {
+
+    private static final String xml = "<functions>\n" +
+            "   <functions class=\"java.util.ArrayList\">\n" +
+            "      <function>\n" +
+            "         <name>test</name>\n" +
+            "         <body>x+y</body>\n" +
+            "         <parameterNames class=\"java.util.ArrayList\">\n" +
+            "            <string>x</string>\n" +
+            "            <string>y</string>\n" +
+            "         </parameterNames>\n" +
+            "         <system>false</system>\n" +
+            "         <description>description</description>\n" +
+            "      </function>\n" +
+            "      <function>\n" +
+            "         <name>z_2</name>\n" +
+            "         <body>e^(z_1^2+z_2^2)</body>\n" +
+            "         <parameterNames class=\"java.util.ArrayList\">\n" +
+            "            <string>z_1</string>\n" +
+            "            <string>z_2</string>\n" +
+            "         </parameterNames>\n" +
+            "         <system>true</system>\n" +
+            "         <description></description>\n" +
+            "      </function>\n" +
+            "      <function>\n" +
+            "         <name>z_2</name>\n" +
+            "         <body>e^(z_1^2+z_2^2)</body>\n" +
+            "         <parameterNames class=\"java.util.ArrayList\">\n" +
+            "            <string>z_1</string>\n" +
+            "            <string>z_2</string>\n" +
+            "         </parameterNames>\n" +
+            "         <system>true</system>\n" +
+            "         <description></description>\n" +
+            "      </function>\n" +
+            "   </functions>\n" +
+            "</functions>";
+
+    @Test
+    public void testXml() throws Exception {
+        final Functions in = new Functions();
+
+        AFunction first = new AFunction.Builder("test", "x+y", Arrays.asList("x", "y")).setDescription("description").setSystem(false).create();
+        in.getEntities().add(first);
+
+        AFunction second = new AFunction.Builder("z_2", "e^(z_1^2+z_2^2)", Arrays.asList("z_1", "z_2")).setSystem(true).create();
+        in.getEntities().add(second);
+
+        AFunction third = new AFunction.Builder("z_2", "e^(z_1^2+z_2^2)", Arrays.asList("z_1", "z_2")).setSystem(true).setDescription("").create();
+        in.getEntities().add(third);
+
+        final Functions out = testXml(in, xml);
+
+        Assert.assertTrue(!out.getEntities().isEmpty());
+
+        final AFunction firstOut = out.getEntities().get(0);
+        final AFunction secondOut = out.getEntities().get(1);
+
+        assertEquals(first, firstOut);
+        assertEquals(second, secondOut);
+
+    }
+
+    @NotNull
+    private Functions testXml(@NotNull Functions in, @Nullable String expectedXml) throws Exception {
+        final String actualXml = toXml(in);
+
+        if (expectedXml != null) {
+            Assert.assertEquals(expectedXml, actualXml);
+        }
+
+        final Serializer serializer = new Persister();
+        final Functions out = serializer.read(Functions.class, actualXml);
+        final String actualXml2 = toXml(out);
+        Assert.assertEquals(actualXml, actualXml2);
+        return out;
+    }
+
+    private String toXml(Functions in) throws Exception {
+        final StringWriter sw = new StringWriter();
+        final Serializer serializer = new Persister();
+        serializer.write(in, sw);
+        return sw.toString();
+    }
+
+    @Test
+    public void testRandomXml() throws Exception {
+        final Functions in = new Functions();
+
+        final Random random = new Random(new Date().getTime());
+
+        ExpressionGenerator generator = new ExpressionGenerator(10);
+        for (  int i = 0; i < 1000; i++ ) {
+            final String content = generator.generate();
+
+            final String paramsString = StringUtils.generateRandomString(random.nextInt(10));
+            final List<String> parameterNames = new ArrayList<String>();
+            for (int j = 0; j < paramsString.length(); j++) {
+                parameterNames.add(String.valueOf(paramsString.charAt(j)));
+            }
+
+            final AFunction.Builder builder = new AFunction.Builder("test_" + i, content, parameterNames);
+
+            if ( random.nextBoolean() ) {
+                builder.setDescription(StringUtils.generateRandomString(random.nextInt(100)));
+            }
+
+            builder.setSystem(random.nextBoolean());
+
+            in.getEntities().add(builder.create());
+        }
+
+        testXml(in, null);
+    }
+
+    private void assertEquals(@NotNull final AFunction expected,
+                              @NotNull AFunction actual) {
+        //Assert.assertEquals(expected.getId(), actual.getId());
+        Assert.assertEquals(expected.getContent(), actual.getContent());
+        Assert.assertEquals(expected.getDescription(), actual.getDescription());
+        Assert.assertEquals(expected.getName(), actual.getName());
+        Assert.assertThat(actual.getParameterNames(), new BaseMatcher<List<String>>() {
+            @Override
+            public boolean matches(Object item) {
+                return EqualsUtils.areEqual(expected.getParameterNames(), (List<String>)item, new CollectionEqualizer<String>(null));
+            }
+
+            @Override
+            public void describeTo(Description description) {
+            }
+        });
+    }
+}

calculatorpp/res/values-es/text_strings.xml

@@ -49,7 +49,7 @@
 	<string name="c_remove">Borrar</string>
 	<string name="c_yes">Si</string>
 	<string name="c_no">No</string>
-	<string name="c_var_removal_confirmation">Confirmación de Borrado</string>
+	<string name="removal_confirmation">Confirmación de Borrado</string>
 	<string name="c_var_removal_confirmation_question">¿Realmente desea borrar la variable \'%s\'?</string>
 	<string name="c_var_name">Nombre</string>
 	<string name="c_var_value">Valor</string>

calculatorpp/res/values-it/text_strings.xml

@@ -49,7 +49,7 @@
 	<string name="c_remove">Rimuovi</string>
 	<string name="c_yes">Sì</string>
 	<string name="c_no">No</string>
-	<string name="c_var_removal_confirmation">Conferma rimozione</string>
+	<string name="removal_confirmation">Conferma rimozione</string>
 	<string name="c_var_removal_confirmation_question">Vuoi davvero cancellare la variabile \'%s\'?</string>
 	<string name="c_var_name">Nome</string>
 	<string name="c_var_value">Valore</string>

calculatorpp/res/values-ru/text_strings.xml

@@ -54,7 +54,7 @@
 	<string name="c_remove">Удалить</string>
 	<string name="c_yes">Да</string>
 	<string name="c_no">Нет</string>
-	<string name="c_var_removal_confirmation">Подтверждение удаления</string>
+	<string name="removal_confirmation">Подтверждение удаления</string>
 	<string name="c_var_removal_confirmation_question">Вы действительно хотите удалить переменную \'%s\'?</string>
 	<string name="c_var_name">Имя</string>
 	<string name="c_var_value">Значение</string>

calculatorpp/res/values-uk/text_strings.xml

@@ -54,7 +54,7 @@
 	<string name="c_remove">Вилучити</string>
 	<string name="c_yes">Так</string>
 	<string name="c_no">Ні</string>
-	<string name="c_var_removal_confirmation">Підтвердження вилучення</string>
+	<string name="removal_confirmation">Підтвердження вилучення</string>
 	<string name="c_var_removal_confirmation_question">Ви дійсно хочете вилучити змінну \'%s\'?</string>
 	<string name="c_var_name">Ім’я</string>
 	<string name="c_var_value">Значення</string>

calculatorpp/res/values-zh-rtw/text_strings.xml

@@ -54,7 +54,7 @@
 	<string name="c_remove">移除</string>
 	<string name="c_yes">是</string>
 	<string name="c_no">否</string>
-	<string name="c_var_removal_confirmation">確認移除</string>
+	<string name="removal_confirmation">確認移除</string>
 	<string name="c_var_removal_confirmation_question">您真的要移除變數 \'%s\' 嗎?</string>
 	<string name="c_var_name">名稱</string>
 	<string name="c_var_value">值</string>

calculatorpp/res/values/text_strings.xml

@@ -54,7 +54,7 @@
 	<string name="c_remove">Remove</string>
 	<string name="c_yes">Yes</string>
 	<string name="c_no">No</string>
-	<string name="c_var_removal_confirmation">Removal confirmation</string>
+	<string name="removal_confirmation">Removal confirmation</string>
 	<string name="c_var_removal_confirmation_question">Do you really want to delete \'%s\' variable?</string>
 	<string name="c_var_name">Name</string>
 	<string name="c_var_value">Value</string>
@@ -246,5 +246,6 @@
 	<string name="function_name_clashes">Function name clashes with function name!</string>
 	<string name="function_is_empty">Function body could not be empty!</string>
 	<string name="function_param_not_empty">Function parameter should not be empty!</string>
+    <string name="function_removal_confirmation_question">Do you really want to delete \'%s\' function?</string>
 
 </resources>

calculatorpp/src/main/java/org/solovyev/android/calculator/function/FunctionEditDialogFragment.java

@@ -6,20 +6,19 @@ import android.support.v4.app.FragmentManager;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
+import android.widget.EditText;
 import jscl.math.function.CustomFunction;
 import jscl.math.function.Function;
 import jscl.math.function.IFunction;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.solovyev.android.AndroidUtils2;
-import org.solovyev.android.calculator.CalculatorEventData;
+import org.solovyev.android.calculator.*;
-import org.solovyev.android.calculator.CalculatorEventListener;
-import org.solovyev.android.calculator.CalculatorEventType;
-import org.solovyev.android.calculator.CalculatorLocatorImpl;
-import org.solovyev.android.calculator.R;
 import org.solovyev.android.calculator.math.edit.MathEntityRemover;
 import org.solovyev.android.calculator.model.AFunction;
 
+import java.util.List;
+
 /**
  * User: serso
  * Date: 11/13/12
@@ -30,9 +29,6 @@ public class FunctionEditDialogFragment extends DialogFragment implements Calcul
     @NotNull
     private final Input input;
 
-	@NotNull
-	private FunctionParamsView paramsView;
-
     public FunctionEditDialogFragment() {
         this(Input.newInstance());
     }
@@ -50,18 +46,34 @@ public class FunctionEditDialogFragment extends DialogFragment implements Calcul
     public void onViewCreated(@NotNull View root, Bundle savedInstanceState) {
         super.onViewCreated(root, savedInstanceState);
 
-		paramsView = (FunctionParamsView) root.findViewById(R.id.function_params_layout);
+        final FunctionParamsView paramsView = (FunctionParamsView) root.findViewById(R.id.function_params_layout);
 
 		final AFunction.Builder builder;
 		final IFunction function = input.getFunction();
 		if (function != null) {
 			builder = new AFunction.Builder(function);
-			paramsView.init(function.getParameterNames());
 		} else {
 			builder = new AFunction.Builder();
+        }
+
+        final List<String> parameterNames = input.getParameterNames();
+        if (parameterNames != null) {
+            paramsView.init(parameterNames);
+        } else {
             paramsView.init();
         }
 
+        final EditText editName = (EditText) root.findViewById(R.id.function_edit_name);
+        // show soft keyboard automatically
+        editName.requestFocus();
+        editName.setText(input.getName());
+
+        final EditText editDescription = (EditText) root.findViewById(R.id.function_edit_description);
+        editDescription.setText(input.getDescription());
+
+        final EditText editContent = (EditText) root.findViewById(R.id.function_edit_value);
+        editContent.setText(input.getContent());
+
 		root.findViewById(R.id.cancel_button).setOnClickListener(new View.OnClickListener() {
 			@Override
 			public void onClick(View v) {
@@ -81,7 +93,7 @@ public class FunctionEditDialogFragment extends DialogFragment implements Calcul
 			getDialog().setTitle(R.string.function_edit_function);
 
 			Function customFunction = new CustomFunction.Builder(function).create();
-			root.findViewById(R.id.remove_button).setOnClickListener(new MathEntityRemover<Function>(customFunction, null, CalculatorLocatorImpl.getInstance().getEngine().getFunctionsRegistry(), getActivity(), this));
+			root.findViewById(R.id.remove_button).setOnClickListener(MathEntityRemover.newFunctionRemover(customFunction, null, this.getActivity(), FunctionEditDialogFragment.this));
 		}
 	}
 
@@ -105,7 +117,7 @@ public class FunctionEditDialogFragment extends DialogFragment implements Calcul
 			case function_removed:
 			case function_added:
 			case function_changed:
-				if ( calculatorEventData.getSource() == this ) {
+				if ( calculatorEventData.getSource() == FunctionEditDialogFragment.this ) {
 					dismiss();
 				}
 				break;
@@ -134,11 +146,14 @@ public class FunctionEditDialogFragment extends DialogFragment implements Calcul
         private String name;
 
         @Nullable
-        private String value;
+        private String content;
 
         @Nullable
         private String description;
 
+        @Nullable
+        private List<String> parameterNames;
+
         private Input() {
         }
 
@@ -157,16 +172,20 @@ public class FunctionEditDialogFragment extends DialogFragment implements Calcul
         @NotNull
         public static Input newFromValue(@Nullable String value) {
             final Input result = new Input();
-            result.value = value;
+            result.content = value;
             return result;
         }
 
         @NotNull
-        public static Input newInstance(@Nullable IFunction function, @Nullable String name, @Nullable String value, @Nullable String description) {
+        public static Input newInstance(@Nullable IFunction function,
+                                        @Nullable String name,
+                                        @Nullable String value,
+                                        @Nullable String description) {
+
             final Input result = new Input();
             result.function = function;
             result.name = name;
-            result.value = value;
+            result.content = value;
             result.description = description;
             return result;
         }
@@ -182,13 +201,18 @@ public class FunctionEditDialogFragment extends DialogFragment implements Calcul
         }
 
         @Nullable
-        public String getValue() {
+        public String getContent() {
-            return value == null ? (function == null ? null : function.getContent()) : value;
+            return content == null ? (function == null ? null : function.getContent()) : content;
         }
 
         @Nullable
         public String getDescription() {
-            return description == null ? (function == null ? null : function.getContent()) : description;
+            return description == null ? (function == null ? null : function.getDescription()) : description;
+        }
+
+        @Nullable
+        public List<String> getParameterNames() {
+            return parameterNames == null ? (function == null ? null : function.getParameterNames()) : parameterNames;
         }
     }
 }

calculatorpp/src/main/java/org/solovyev/android/calculator/function/FunctionEditorSaver.java

@@ -11,7 +11,6 @@ import org.solovyev.android.calculator.CalculatorFunctionsMathRegistry;
 import org.solovyev.android.calculator.CalculatorLocatorImpl;
 import org.solovyev.android.calculator.CalculatorMathRegistry;
 import org.solovyev.android.calculator.R;
-import org.solovyev.android.calculator.math.MathType;
 import org.solovyev.android.calculator.math.edit.VarEditorSaver;
 import org.solovyev.android.calculator.model.AFunction;
 import org.solovyev.android.calculator.model.MathEntityBuilder;
@@ -84,9 +83,6 @@ public class FunctionEditorSaver implements View.OnClickListener {
 
 			if (canBeSaved) {
 				if (validateParameters(parameterNames)) {
-					final MathType.Result mathType = MathType.getType(name, 0, false);
-
-					if (mathType.getMathType() == MathType.text || mathType.getMathType() == MathType.function ) {
 
                     if (!StringUtils.isEmpty(content)) {
                         builder.setParameterNames(parameterNames);
@@ -97,9 +93,6 @@ public class FunctionEditorSaver implements View.OnClickListener {
                     } else {
                         error = R.string.function_is_empty;
                     }
-					} else {
-						error = R.string.function_name_clashes;
-					}
                 } else {
 					error = R.string.function_param_not_empty;
 				}

calculatorpp/src/main/java/org/solovyev/android/calculator/math/edit/CalculatorVarsFragment.java

@@ -234,7 +234,7 @@ public class CalculatorVarsFragment extends AbstractMathEntityListFragment<ICons
         remove(R.string.c_remove) {
             @Override
             public void onClick(@NotNull IConstant constant, @NotNull Context context) {
-                new MathEntityRemover<IConstant>(constant, null, CalculatorLocatorImpl.getInstance().getEngine().getVarsRegistry(), context, context).showConfirmationDialog();
+                MathEntityRemover.newConstantRemover(constant, null, context, context).showConfirmationDialog();
             }
         },
 

calculatorpp/src/main/java/org/solovyev/android/calculator/math/edit/MathEntityRemover.java

@@ -11,6 +11,8 @@ import android.content.Context;
 import android.content.DialogInterface;
 import android.view.View;
 import android.widget.TextView;
+import jscl.math.function.Function;
+import jscl.math.function.IConstant;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.solovyev.android.calculator.CalculatorEventType;
@@ -43,40 +45,66 @@ public class MathEntityRemover<T extends MathEntity> implements View.OnClickList
     @NotNull
     private final Object source;
 
-    public MathEntityRemover(@NotNull T mathEntity,
+    @NotNull
-                             @Nullable DialogInterface.OnClickListener callbackOnCancel,
+    private final Params params;
-                             @NotNull CalculatorMathRegistry<? super T> varsRegistry,
-                             @NotNull Context context,
-                             @NotNull Object source) {
-		this(mathEntity, callbackOnCancel, false, varsRegistry, context, source);
-	}
 
-	public MathEntityRemover(@NotNull T mathEntity,
+    /*
+    **********************************************************************
+    *
+    *                           CONSTRUCTORS
+    *
+    **********************************************************************
+    */
+
+	private MathEntityRemover(@NotNull T mathEntity,
                              @Nullable DialogInterface.OnClickListener callbackOnCancel,
                              boolean confirmed,
                              @NotNull CalculatorMathRegistry<? super T> varsRegistry,
                              @NotNull Context context,
-                             @NotNull Object source) {
+                             @NotNull Object source,
+                             @NotNull Params params) {
 		this.mathEntity = mathEntity;
 		this.callbackOnCancel = callbackOnCancel;
 		this.confirmed = confirmed;
 		this.varsRegistry = varsRegistry;
         this.context = context;
         this.source = source;
+        this.params = params;
     }
 
+    public static MathEntityRemover<IConstant> newConstantRemover(@NotNull IConstant constant,
+                                                                  @Nullable DialogInterface.OnClickListener callbackOnCancel,
+                                                                  @NotNull Context context,
+                                                                  @NotNull Object source) {
+        return new MathEntityRemover<IConstant>(constant, callbackOnCancel, false, CalculatorLocatorImpl.getInstance().getEngine().getVarsRegistry(), context, source, Params.newConstantInstance());
+    }
+
+    public static MathEntityRemover<Function> newFunctionRemover(@NotNull Function function,
+                                                                  @Nullable DialogInterface.OnClickListener callbackOnCancel,
+                                                                  @NotNull Context context,
+                                                                  @NotNull Object source) {
+        return new MathEntityRemover<Function>(function, callbackOnCancel, false, CalculatorLocatorImpl.getInstance().getEngine().getFunctionsRegistry(), context, source, Params.newFunctionInstance());
+    }
+
+    /*
+    **********************************************************************
+    *
+    *                           METHODS
+    *
+    **********************************************************************
+    */
 
 
     public void showConfirmationDialog() {
         final TextView question = new TextView(context);
-		question.setText(String.format(context.getString(R.string.c_var_removal_confirmation_question), mathEntity.getName()));
+        question.setText(String.format(context.getString(params.getRemovalConfirmationQuestionResId()), mathEntity.getName()));
         question.setPadding(6, 6, 6, 6);
         final AlertDialog.Builder builder = new AlertDialog.Builder(context)
                 .setCancelable(true)
                 .setView(question)
-				.setTitle(R.string.c_var_removal_confirmation)
+                .setTitle(params.getRemovalConfirmationTitleResId())
                 .setNegativeButton(R.string.c_no, callbackOnCancel)
-				.setPositiveButton(R.string.c_yes, new MathEntityRemover<T>(mathEntity, callbackOnCancel, true, varsRegistry, context, source));
+                .setPositiveButton(R.string.c_yes, new MathEntityRemover<T>(mathEntity, callbackOnCancel, true, varsRegistry, context, source, params));
 
         builder.create().show();
     }
@@ -89,7 +117,7 @@ public class MathEntityRemover<T extends MathEntity> implements View.OnClickList
             varsRegistry.remove(mathEntity);
             varsRegistry.save();
 
-            CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(CalculatorEventType.constant_removed, mathEntity, source);
+            CalculatorLocatorImpl.getInstance().getCalculator().fireCalculatorEvent(params.getCalculatorEventType(), mathEntity, source);
         }
     }
 
@@ -97,4 +125,52 @@ public class MathEntityRemover<T extends MathEntity> implements View.OnClickList
     public void onClick(DialogInterface dialog, int which) {
         onClick(null);
     }
+
+    /*
+    **********************************************************************
+    *
+    *                           STATIC
+    *
+    **********************************************************************
+    */
+
+    private static final class Params {
+
+        private int removalConfirmationTitleResId;
+
+        private int removalConfirmationQuestionResId;
+
+        private CalculatorEventType calculatorEventType;
+
+        private Params() {
+        }
+
+        public int getRemovalConfirmationTitleResId() {
+            return removalConfirmationTitleResId;
+        }
+
+        public int getRemovalConfirmationQuestionResId() {
+            return removalConfirmationQuestionResId;
+        }
+
+        public CalculatorEventType getCalculatorEventType() {
+            return calculatorEventType;
+        }
+
+        private static <T extends MathEntity> Params newConstantInstance() {
+            final Params result = new Params();
+            result.removalConfirmationTitleResId = R.string.removal_confirmation;
+            result.removalConfirmationQuestionResId = R.string.c_var_removal_confirmation_question;
+            result.calculatorEventType = CalculatorEventType.constant_removed;
+            return result;
+        }
+
+        private static <T extends MathEntity> Params newFunctionInstance() {
+            final Params result = new Params();
+            result.removalConfirmationTitleResId = R.string.removal_confirmation;
+            result.removalConfirmationQuestionResId = R.string.function_removal_confirmation_question;
+            result.calculatorEventType = CalculatorEventType.function_removed;
+            return result;
+        }
+    }
 }

calculatorpp/src/main/java/org/solovyev/android/calculator/math/edit/VarEditDialogFragment.java

@@ -121,7 +121,7 @@ public class VarEditDialogFragment extends DialogFragment implements CalculatorE
             // EDIT MODE
             getDialog().setTitle(R.string.c_var_edit_var);
 
-            root.findViewById(R.id.remove_button).setOnClickListener(new MathEntityRemover<IConstant>(constant, null, CalculatorLocatorImpl.getInstance().getEngine().getVarsRegistry(), getActivity(), this));
+            root.findViewById(R.id.remove_button).setOnClickListener(MathEntityRemover.newConstantRemover(constant, null, getActivity(), VarEditDialogFragment.this));
         }
     }