added static validColorString function, returns true if the color string is in valid color format

2 files changed, 17 insertions, 5 deletions

diff --git a/src/FbTk/Color.cc b/src/FbTk/Color.cc
index 7d050d3..dd80bd3 100644
--- a/src/FbTk/Color.cc
+++ b/src/FbTk/Color.cc
@@ -31,11 +31,9 @@
 using namespace std;
 
 namespace {
-unsigned char maxValue(unsigned short colval) {
-    if (colval == 65535) 
-        return 0xFF;
 
-    return static_cast<unsigned char>(colval/0xFF);
+inline unsigned char maxValue(unsigned short colval) {
+   return colval == 65535 ? 0xFF : static_cast<unsigned char>(colval/0xFF);
 }
 
 };
@@ -106,6 +104,17 @@ bool Color::setFromString(const char *color_string, int screen) {
     return true;
 }
 
+bool Color::validColorString(const char *color_string, int screen) {
+    XColor color;
+    Display *disp = App::instance()->display();
+    Colormap colm = DefaultColormap(disp, screen);   
+    // trim white space
+    string color_string_tmp = color_string;
+    StringUtil::removeFirstWhitespace(color_string_tmp);
+    StringUtil::removeTrailingWhitespace(color_string_tmp);
+
+    return XParseColor(disp, colm, color_string_tmp.c_str(), &color) != 0;
+}
 
 Color &Color::operator  = (const Color &col_copy) {
     // check for aliasing
diff --git a/src/FbTk/Color.hh b/src/FbTk/Color.hh
index b17dd95..7536d89 100644
--- a/src/FbTk/Color.hh
+++ b/src/FbTk/Color.hh
@@ -54,7 +54,10 @@ public:
     inline unsigned short green() const { return m_green; }
     inline unsigned short blue() const { return m_blue; }
     inline unsigned long pixel() const { return m_pixel; }
-        
+
+    /// @return true if the color name in color_string is resolved, else false
+    static bool validColorString(const char *color_string, int screen);
+
 private:
     void free();
     void copy(const Color &col);