From b74bec6cd3fa92b1ccbf3f3da68e54fe7c889bd7 Mon Sep 17 00:00:00 2001
From: Sergey Solovyev <se.solovyev@gmail.com>
Date: Fri, 10 Feb 2012 23:54:03 +0400
Subject: [PATCH] android_calculator-55: Error label is very annoying

---
 res/values/colors.xml                                  |  1 +
 .../solovyev/android/calculator/CalculatorDisplay.java |  3 +++
 .../solovyev/android/calculator/CalculatorModel.java   | 10 ++++++++--
 .../calculator/history/AbstractHistoryActivity.java    |  2 ++
 4 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/res/values/colors.xml b/res/values/colors.xml
index b1e5576f..c45dbe16 100644
--- a/res/values/colors.xml
+++ b/res/values/colors.xml
@@ -10,6 +10,7 @@
 	<color name="button_operator_text_color">#ffffff99</color>
 	<color name="button_ce_text_color">#ffffffff</color>
 	<color name="default_text_color">#ffffffff</color>
+	<color name="display_error_text_color">#44ffffff</color>
 	<color name="selected_angle_unit_text_color">#ffffff99</color>
 	<color name="default_background">#ff000000</color>
 </resources>
\ No newline at end of file
diff --git a/src/main/java/org/solovyev/android/calculator/CalculatorDisplay.java b/src/main/java/org/solovyev/android/calculator/CalculatorDisplay.java
index e4992d08..7e684d3a 100644
--- a/src/main/java/org/solovyev/android/calculator/CalculatorDisplay.java
+++ b/src/main/java/org/solovyev/android/calculator/CalculatorDisplay.java
@@ -133,6 +133,9 @@ public class CalculatorDisplay extends AutoResizeTextView implements ICalculator
 		this.valid = valid;
 		if (valid) {
 			errorMessage = null;
+			setTextColor(getResources().getColor(R.color.default_text_color));
+		} else {
+			setTextColor(getResources().getColor(R.color.display_error_text_color));
 		}
 	}
 
diff --git a/src/main/java/org/solovyev/android/calculator/CalculatorModel.java b/src/main/java/org/solovyev/android/calculator/CalculatorModel.java
index a7c7871f..29c7c441 100644
--- a/src/main/java/org/solovyev/android/calculator/CalculatorModel.java
+++ b/src/main/java/org/solovyev/android/calculator/CalculatorModel.java
@@ -172,9 +172,10 @@ public enum CalculatorModel implements CursorControl, HistoryControl<CalculatorH
 
 		final CalculatorHistoryState localHistoryState;
 		if (historyState == null) {
-			this.display.setText("");
+			//this.display.setText("");
 			localHistoryState = getCurrentHistoryState();
 		} else {
+			this.display.setText(historyState.getDisplayState().getEditorState().getText());
 			localHistoryState = historyState;
 		}
 
@@ -263,7 +264,12 @@ public enum CalculatorModel implements CursorControl, HistoryControl<CalculatorH
 										   @NotNull JsclOperation operation,
 										   @NotNull Message e) {
 		Log.d(CalculatorModel.class.getName(), "Evaluation failed for : " + expression + ". Error message: " + e);
-		localDisplay.setText(R.string.c_syntax_error);
+		if ( StringUtils.isEmpty(localDisplay.getText()) ) {
+			// if previous display state was empty -> show error
+			localDisplay.setText(R.string.c_syntax_error);
+		} else {
+			// show previous result instead of error caption (actually previous result will be greyed)
+		}
 		localDisplay.setJsclOperation(operation);
 		localDisplay.setGenericResult(null);
 		localDisplay.setValid(false);
diff --git a/src/main/java/org/solovyev/android/calculator/history/AbstractHistoryActivity.java b/src/main/java/org/solovyev/android/calculator/history/AbstractHistoryActivity.java
index 7acdee4c..fea99c8d 100644
--- a/src/main/java/org/solovyev/android/calculator/history/AbstractHistoryActivity.java
+++ b/src/main/java/org/solovyev/android/calculator/history/AbstractHistoryActivity.java
@@ -171,6 +171,8 @@ public abstract class AbstractHistoryActivity extends ListActivity {
 
 	public static void useHistoryItem(@NotNull final CalculatorHistoryState historyState, @NotNull AbstractHistoryActivity activity) {
 
+		// before evaluating history item - clear display (in order to get Error message in display if evaluation fail)
+		CalculatorModel.instance.getDisplay().setText("");
 		CalculatorModel.instance.doTextOperation(new CalculatorModel.TextOperation() {
 			@Override
 			public void doOperation(@NotNull EditText editor) {