var activity

res/layout/var.xml

@@ -29,4 +29,13 @@
 
 	</LinearLayout>
 
+	<TextView a:id="@+id/var_description"
+			  a:layout_width="match_parent"
+			  a:layout_height="match_parent"
+			  a:paddingBottom="6dp"
+			  a:paddingLeft="6dp"
+			  a:paddingRight="6dp"
+			  a:paddingTop="0dp">
+	</TextView>
+
 </LinearLayout>

res/layout/var_edit.xml

@@ -16,7 +16,7 @@
 			  a:layout_width="wrap_content"
 			  a:text="Name"/>
 
-	<EditText a:id="@+id/var_name"
+	<EditText a:id="@+id/var_edit_name"
 			  a:layout_width="match_parent"
 			  a:layout_height="match_parent"
 			  a:textSize="20dp">
@@ -26,7 +26,7 @@
 			  a:layout_width="wrap_content"
 			  a:text="Value"/>
 
-	<EditText a:id="@+id/var_value"
+	<EditText a:id="@+id/var_edit_value"
 			  a:layout_width="match_parent"
 			  a:layout_height="match_parent"
 			  a:inputType="number"
@@ -37,7 +37,7 @@
 			  a:layout_width="wrap_content"
 			  a:text="Description"/>
 
-	<EditText a:id="@+id/var_description"
+	<EditText a:id="@+id/var_edit_description"
 			  a:layout_width="match_parent"
 			  a:layout_height="match_parent"
 			  a:textSize="20dp">

res/menu/main_menu.xml

@@ -2,9 +2,12 @@
 
 <menu xmlns:a="http://schemas.android.com/apk/res/android">
 
-	<item a:id="@+id/menu_item_settings"
+	<item a:id="@+id/main_menu_item_settings"
 		  a:title="@string/c_settings"/>
 
-	<item a:id="@+id/menu_item_about"
+	<item a:id="@+id/main_menu_item_about"
 		  a:title="@string/c_about"/>
+
+	<item a:id="@+id/main_menu_item_exit"
+		  a:title="@string/c_exit"/>
 </menu>

res/menu/var_menu.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+  ~ For more information, please, contact se.solovyev@gmail.com
+  ~ or visit http://se.solovyev.org
+  -->
+
+<menu xmlns:a="http://schemas.android.com/apk/res/android">
+
+	<item a:id="@+id/var_menu_add_var"
+		  a:title="@string/c_add"/>
+</menu>

res/values/colors.xml

@@ -1,4 +1,5 @@
 <resources>
     <color name="magic_flame">#00ffffff</color>
-    <color name="button_text">#ffffffff</color>
+    <color name="button_text_color">#ffffffff</color>
+    <color name="text_color">#ffffffff</color>
 </resources>

res/values/strings.xml

@@ -33,4 +33,8 @@
 
 	<string name="c_calc_color_display_title">Color expressions</string>
 	<string name="p_calc_result_precision_title">Precision of result</string>
+	<string name="c_exit">Exit</string>
+	<string name="c_add">Add</string>
+	<string name="c_cancel">Cancel</string>
+	<string name="c_save">Save</string>
 </resources>

res/values/styles.xml

@@ -29,7 +29,7 @@
     <style name="display_style">
         <item name="android:textSize">25dp</item>
         <item name="android:background">#000000</item>
-        <item name="android:textColor">#ffffff</item>
+        <item name="android:textColor">@color/text_color</item>
         <item name="android:gravity">left|top</item>
 		<item name="android:padding">5dp</item>
         <item name="android:layout_width">match_parent</item>

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

@@ -234,14 +234,18 @@ public class CalculatorActivity extends Activity implements FontSizeAdjuster, Sh
 		boolean result;
 
 		switch (item.getItemId()) {
-			case R.id.menu_item_settings:
+			case R.id.main_menu_item_settings:
 				showSettings();
 				result = true;
 				break;
-			case R.id.menu_item_about:
+			case R.id.main_menu_item_about:
 				showAbout();
 				result = true;
 				break;
+			case R.id.main_menu_item_exit:
+				this.finish();
+				result = true;
+				break;
 			default:
 				result = super.onOptionsItemSelected(item);
 		}

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

@@ -5,9 +5,7 @@
 
 package org.solovyev.android.calculator;
 
-import android.content.Intent;
 import android.os.Bundle;
-import android.preference.Preference;
 import android.preference.PreferenceActivity;
 
 /**
@@ -21,6 +19,6 @@ public class CalculatorPreferencesActivity extends PreferenceActivity {
 	protected void onCreate(Bundle savedInstanceState) {
 		super.onCreate(savedInstanceState);
 
-		addPreferencesFromResource(R.xml.preferences);
+		addPreferencesFromResource(R.xml.main_preferences);
 	}
 }

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

@@ -12,10 +12,10 @@ import android.content.Context;
 import android.content.DialogInterface;
 import android.content.Intent;
 import android.os.Bundle;
-import android.view.LayoutInflater;
+import android.view.*;
-import android.view.View;
-import android.view.ViewGroup;
 import android.widget.*;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 import org.solovyev.common.utils.StringUtils;
 
 import java.util.ArrayList;
@@ -26,13 +26,17 @@ import java.util.List;
  * Date: 9/28/11
  * Time: 10:55 PM
  */
-public class CalculatorVarsActivity extends ListActivity implements DialogInterface.OnClickListener {
+public class CalculatorVarsActivity extends ListActivity {
+
+	@NotNull
+	private VarsArrayAdapter adapter;
 
 	@Override
 	protected void onCreate(Bundle savedInstanceState) {
 		super.onCreate(savedInstanceState);
 
-		setListAdapter(new VarsArrayAdapter(this, R.layout.var, R.id.var_text, new ArrayList<Var>(CalculatorModel.getInstance().getVarsRegister().getVars())));
+		adapter = new VarsArrayAdapter(this, R.layout.var, R.id.var_text, new ArrayList<Var>(CalculatorModel.getInstance().getVarsRegister().getVars()));
+		setListAdapter(adapter);
 
 		final ListView lv = getListView();
 		lv.setTextFilterEnabled(true);
@@ -41,23 +45,8 @@ public class CalculatorVarsActivity extends ListActivity implements DialogInterf
 		lv.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
 			@Override
 			public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
-				final LayoutInflater layoutInflater = (LayoutInflater) getSystemService(LAYOUT_INFLATER_SERVICE);
-				final View editView = layoutInflater.inflate(R.layout.var_edit, null);
-
 				final Var var = (Var) parent.getItemAtPosition(position);
-
+				createEditVariableDialog(var, var.getName(), var.getValue(), var.getDescription());
-				final EditText editName = (EditText)editView.findViewById(R.id.var_name);
-				editName.setText(var.getName());
-				final EditText editValue = (EditText)editView.findViewById(R.id.var_value);
-				editValue.setText(var.getValue());
-				final EditText editDescription = (EditText)editView.findViewById(R.id.var_description);
-				editDescription.setText(var.getDescription());
-
-
-				new AlertDialog.Builder(CalculatorVarsActivity.this)
-						.setCancelable(true)
-						.setPositiveButton("Save", CalculatorVarsActivity.this)
-						.setView(editView).create().show();
 				return true;
 			}
 		});
@@ -75,9 +64,118 @@ public class CalculatorVarsActivity extends ListActivity implements DialogInterf
 
 	}
 
+	private void createEditVariableDialog(@Nullable Var var, @Nullable String name, @Nullable String value, @Nullable String description) {
+		if (var == null || !var.isSystem()) {
+
+			final LayoutInflater layoutInflater = (LayoutInflater) getSystemService(LAYOUT_INFLATER_SERVICE);
+			final View editView = layoutInflater.inflate(R.layout.var_edit, null);
+
+			final EditText editName = (EditText) editView.findViewById(R.id.var_edit_name);
+			editName.setText(name);
+
+			final EditText editValue = (EditText) editView.findViewById(R.id.var_edit_value);
+			editValue.setText(value);
+
+			final EditText editDescription = (EditText) editView.findViewById(R.id.var_edit_description);
+			editDescription.setText(description);
+
+			final Var.Builder varBuilder;
+			if (var != null) {
+				varBuilder = new Var.Builder(var);
+			} else {
+				varBuilder = new Var.Builder();
+			}
+
+			new AlertDialog.Builder(this)
+					.setCancelable(true)
+					.setNegativeButton(getString(R.string.c_cancel), new DialogInterface.OnClickListener() {
 						@Override
 						public void onClick(DialogInterface dialog, int which) {
-		//To change body of implemented methods use File | Settings | File Templates.
+							// do nothing
+						}
+					})
+					.setPositiveButton(getString(R.string.c_save), new VarEditorSaver(varBuilder, var, editView))
+					.setView(editView).create().show();
+		} else {
+			Toast.makeText(this, "System variable cannot be changed!", Toast.LENGTH_LONG).show();
+		}
+	}
+
+	private class VarEditorSaver implements DialogInterface.OnClickListener {
+
+		@NotNull
+		private Var.Builder varBuilder;
+
+		@Nullable
+		private final Var editedInstance;
+
+		@NotNull
+		private View editView;
+
+		public VarEditorSaver(@NotNull Var.Builder varBuilder, @Nullable Var editedInstance, @NotNull View editView) {
+			this.varBuilder = varBuilder;
+			this.editedInstance = editedInstance;
+			this.editView = editView;
+		}
+
+		@Override
+		public void onClick(DialogInterface dialog, int which) {
+			if (which == DialogInterface.BUTTON_POSITIVE) {
+				final String error;
+
+				final EditText editName = (EditText) editView.findViewById(R.id.var_edit_name);
+				String name = editName.getText().toString();
+
+				final EditText editValue = (EditText) editView.findViewById(R.id.var_edit_value);
+				String value = editValue.getText().toString();
+
+				final EditText editDescription = (EditText) editView.findViewById(R.id.var_edit_description);
+				String description = editDescription.getText().toString();
+
+
+				final VarsRegister varsRegister = CalculatorModel.getInstance().getVarsRegister();
+				if (!StringUtils.isEmpty(name)) {
+					final Var varFromRegister = varsRegister.getVar(name);
+					if (varFromRegister == null || varFromRegister == editedInstance) {
+
+						boolean correctDouble = true;
+						try {
+							Double.valueOf(value);
+						} catch (NumberFormatException e) {
+							correctDouble = false;
+						}
+
+						if (correctDouble) {
+							varBuilder.setName(name);
+							varBuilder.setValue(value);
+							varBuilder.setDescription(description);
+							error = null;
+						} else {
+							error = "Value is not a number!";
+						}
+					} else {
+						error = "Variable with same name already exist!";
+					}
+				} else {
+					error = "Name is empty!";
+				}
+
+				if (error != null) {
+					Toast.makeText(CalculatorVarsActivity.this, error, Toast.LENGTH_LONG).show();
+					createEditVariableDialog(editedInstance, name, value, description);
+				} else {
+					if (editedInstance != null && !editedInstance.getName().equals(name)) {
+						varsRegister.addVar(editedInstance.getName(), varBuilder);
+					} else {
+						CalculatorVarsActivity.this.adapter.add(varsRegister.addVar(null, varBuilder));
+					}
+
+					varsRegister.save(CalculatorVarsActivity.this);
+
+					CalculatorVarsActivity.this.adapter.notifyDataSetChanged();
+				}
+			}
+		}
 	}
 
 	private class VarsArrayAdapter extends ArrayAdapter<Var> {
@@ -86,26 +184,54 @@ public class CalculatorVarsActivity extends ListActivity implements DialogInterf
 			super(context, resource, textViewResourceId, objects);
 		}
 
-		public VarsArrayAdapter(Context context, int resource, List<Var> objects) {
-			super(context, resource, objects);
-		}
-
 		@Override
 		public View getView(int position, View convertView, ViewGroup parent) {
 			final ViewGroup result = (ViewGroup) super.getView(position, convertView, parent);
 
-			if (convertView == null) {
 			final Var var = getItem(position);
 
 			if (!StringUtils.isEmpty(var.getDescription())) {
-					final TextView description = new TextView(getContext());
+				TextView description = (TextView) result.findViewById(R.id.var_description);
-					description.setText(var.getDescription());
+				if (description == null) {
-					description.setPadding(6, 0, 6, 6);
+					final LayoutInflater layoutInflater = (LayoutInflater) getSystemService(LAYOUT_INFLATER_SERVICE);
-					result.addView(description, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
+					final ViewGroup itemView = (ViewGroup) layoutInflater.inflate(R.layout.var, null);
+					description = (TextView) itemView.findViewById(R.id.var_description);
+					itemView.removeView(description);
+					result.addView(description);
 				}
+				description.setText(var.getDescription());
+			} else {
+				TextView description = (TextView) result.findViewById(R.id.var_description);
+				if (description != null) {
+					result.removeView(description);
+				}
+			}
+
+
+			return result;
+		}
+	}
+
+	@Override
+	public boolean onCreateOptionsMenu(Menu menu) {
+		final MenuInflater menuInflater = getMenuInflater();
+		menuInflater.inflate(R.menu.var_menu, menu);
+		return true;
+	}
+
+	@Override
+	public boolean onOptionsItemSelected(MenuItem item) {
+		boolean result;
+
+		switch (item.getItemId()) {
+			case R.id.var_menu_add_var:
+				createEditVariableDialog(null, null, null, null);
+				result = true;
+				break;
+			default:
+				result = super.onOptionsItemSelected(item);
 		}
 
 		return result;
 	}
 }
-}

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

@@ -28,23 +28,83 @@ public class Var {
 	@NotNull
 	private String value;
 
+	@Element
 	private boolean system;
 
 	@Element(required = false)
 	@Nullable
 	private String description;
 
-	public Var() {
+	public static class Builder {
+
+		@NotNull
+		private String name;
+
+		@NotNull
+		private String value;
+
+		private boolean system = false;
+
+		@Nullable
+		private String description;
+
+		public Builder() {
 		}
 
-	public Var(@NotNull String name, @NotNull Double value, boolean system) {
+		public Builder(@NotNull Var var) {
-		this(name, String.valueOf(value), system);
+			this.name = var.name;
+			this.value = var.value;
+			this.system = var.system;
+			this.description = var.description;
 		}
 
-	public Var(@NotNull String name, @NotNull String value, boolean system) {
+		public Builder(@NotNull String name, @NotNull Double value) {
+			this(name, String.valueOf(value));
+		}
+
+		public Builder(@NotNull String name, @NotNull String value) {
 			this.name = name;
 			this.value = value;
+		}
+
+		public void setName(@NotNull String name) {
+			this.name = name;
+		}
+
+		public void setValue(@NotNull String value) {
+			this.value = value;
+		}
+
+		protected Builder setSystem(boolean system) {
 			this.system = system;
+			return this;
+		}
+
+		public Builder setDescription(@Nullable String description) {
+			this.description = description;
+			return this;
+		}
+
+		protected Var create () {
+			final Var var = new Var();
+
+			var.name = name;
+			var.value = value;
+			var.system = system;
+			var.description = description;
+
+			return var;
+		}
+	}
+
+	private Var() {
+	}
+
+	public void copy(@NotNull Var var) {
+		this.name = var.name;
+		this.value = var.value;
+		this.description = var.description;
+		this.system = var.system;
 	}
 
 	@NotNull
@@ -52,27 +112,15 @@ public class Var {
 		return value;
 	}
 
-	public void setValue(@NotNull String value) {
-		this.value = value;
-	}
-
 	public boolean isSystem() {
 		return system;
 	}
 
-	public void setSystem(boolean system) {
-		this.system = system;
-	}
-
 	@NotNull
 	public String getName() {
 		return name;
 	}
 
-	public void setName(@NotNull String name) {
-		this.name = name;
-	}
-
 	@Nullable
 	public String getDescription() {
 		return description;

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

@@ -16,7 +16,7 @@ import java.util.List;
 public class Vars {
 
 	@ElementList
-	private final List<Var> vars = new ArrayList<Var>();
+	private List<Var> vars = new ArrayList<Var>();
 
 	public Vars() {
 	}

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

@@ -43,6 +43,19 @@ public class VarsRegister {
 		return Collections.unmodifiableList(systemVars);
 	}
 
+	public Var addVar(@Nullable String name, @NotNull Var.Builder builder) {
+		final Var var = builder.create();
+
+		final Var varFromRegister = getVar(name == null ? var.getName() : name);
+		if (varFromRegister == null) {
+			vars.add(var);
+		} else {
+			varFromRegister.copy(var);
+		}
+
+		return var;
+	}
+
 	@Nullable
 	public Var getVar(@NotNull final String name) {
 		return CollectionsUtils.get(vars, new Finder<Var>() {
@@ -53,6 +66,15 @@ public class VarsRegister {
 		});
 	}
 
+	public boolean contains(@NotNull final String name) {
+		return CollectionsUtils.get(vars, new Finder<Var>() {
+			@Override
+			public boolean isFound(@Nullable Var var) {
+				return var != null && name.equals(var.getName());
+			}
+		}) != null;
+	}
+
 	public void merge(@NotNull final List<Var> varsParam) {
 		final Set<Var> result = new HashSet<Var>(varsParam);
 
@@ -71,17 +93,6 @@ public class VarsRegister {
 		this.vars.clear();
 		this.systemVars.clear();
 
-		Var t = new Var("T", 0d, false);
-		t.setDescription("Some text description!");
-		this.vars.add(t);
-
-		Var t2 = new Var("T2", 2d, false);
-		this.vars.add(t2);
-
-		Var t1 = new Var("T1", 1d, false);
-		t1.setDescription("Не так давно в рунете появились упоминания англоязычного проекта DearPhotograph.com. Сайт нас растрогал, зарядил идеей и вдохновением.");
-		this.vars.add(t1);
-
 		if (context != null) {
 			final SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(context);
 
@@ -98,7 +109,18 @@ public class VarsRegister {
 		}
 
 
-		for (Var systemVar : MathEntityType.constants) {
+		for (String systemVarName : MathEntityType.constants) {
+
+			final Var systemVar;
+			if ( systemVarName.equals("e") ){
+				systemVar = new Var.Builder(systemVarName, Math.E).setSystem(true).create();
+			} else if (systemVarName.equals("π")) {
+				systemVar = new Var.Builder(systemVarName, Math.PI).setSystem(true).create();
+			} else if (systemVarName.equals("i")) {
+				systemVar = new Var.Builder(systemVarName, "√(-1)").setSystem(true).create();
+			} else {
+				throw new IllegalArgumentException(systemVarName + " is not supported yet!");
+			}
 
 			systemVars.add(systemVar);
 			if (!vars.contains(systemVar)) {

src/main/java/org/solovyev/android/calculator/math/MathEntityType.java

@@ -29,14 +29,7 @@ public enum MathEntityType {
 	group_symbols,
 	group_symbol;
 	
-	public static final List<Var> constants;
+	public static final List<String> constants = Arrays.asList("e", "π", "i");
-	static {
-		final List<Var> result = new ArrayList<Var>();
-		result.add(new Var("e", Math.exp(1), true));
-		result.add(new Var("π", Math.PI, true));
-		result.add(new Var("i", "√(-1)", true));
-		constants = Collections.unmodifiableList(result);
-	}
 
 	public static final List<Character> dots = Arrays.asList('.');
 

src/main/java/org/solovyev/android/view/widgets/ColorButton.java

@@ -30,6 +30,7 @@ import android.util.AttributeSet;
 import android.view.MotionEvent;
 import android.widget.Button;
 import org.jetbrains.annotations.NotNull;
+import org.solovyev.android.calculator.R;
 import org.solovyev.android.view.FontSizeAdjuster;
 import org.solovyev.common.utils.Point2d;
 
@@ -68,7 +69,7 @@ public class ColorButton extends Button {
 		mFeedbackPaint = new Paint();
 		mFeedbackPaint.setStyle(Style.STROKE);
 		mFeedbackPaint.setStrokeWidth(2);
-		getPaint().setColor(res.getColor(org.solovyev.android.calculator.R.color.button_text));
+		getPaint().setColor(res.getColor(R.color.button_text_color));
 
 		mAnimStart = -1;