Widget/password field

include/nanogui/textbox.h

@@ -73,6 +73,9 @@ class NANOGUI_EXPORT TextBox : public Widget {
     /// Specify a placeholder text to be displayed while the text box is empty.
     void set_placeholder(const std::string &placeholder) { m_placeholder = placeholder; }
 
+    /// Turn the textbox into a password field.
+    void set_password_field(bool enable, char mask = '*');
+
     /// Set the \ref Theme used to draw this widget
     virtual void set_theme(Theme *theme) override;
 
@@ -105,6 +108,8 @@ class NANOGUI_EXPORT TextBox : public Widget {
     int position_to_cursor_index(float posx, float lastx,
                                  const NVGglyphPosition *glyphs, int size);
 
+    std::string value_or_mask_str(const std::string& str) const;
+
     /// The location (if any) for the spin area.
     enum class SpinArea { None, Top, Bottom };
     SpinArea spin_area(const Vector2i &pos);
@@ -113,6 +118,8 @@ class NANOGUI_EXPORT TextBox : public Widget {
     bool m_editable;
     bool m_spinnable;
     bool m_committed;
+    bool m_password;
+    char m_password_mask;
     std::string m_value;
     std::string m_default_value;
     Alignment m_alignment;

src/textbox.cpp

@@ -27,6 +27,8 @@ TextBox::TextBox(Widget *parent, const std::string &value)
       m_editable(false),
       m_spinnable(false),
       m_committed(true),
+      m_password(false),
+      m_password_mask('*'),
       m_value(value),
       m_default_value(""),
       m_alignment(Alignment::Center),
@@ -211,7 +213,11 @@ void TextBox::draw(NVGcontext* ctx) {
     draw_pos.x() += m_text_offset;
 
     if (m_committed) {
-        nvgText(ctx, draw_pos.x(), draw_pos.y(), m_value.empty() ? m_placeholder.c_str() : m_value.c_str(), nullptr);
+        nvgText(ctx, draw_pos.x(), draw_pos.y(),
+                m_value.empty()
+                ? m_placeholder.c_str()
+                : value_or_mask_str(m_value).c_str()
+                  , nullptr);
     } else {
         const int max_glyphs = 1024;
         NVGglyphPosition glyphs[max_glyphs];
@@ -240,13 +246,18 @@ void TextBox::draw(NVGcontext* ctx) {
         draw_pos.x() = old_draw_pos.x() + m_text_offset;
 
         // draw text with offset
-        nvgText(ctx, draw_pos.x(), draw_pos.y(), m_value_temp.c_str(), nullptr);
-        nvgTextBounds(ctx, draw_pos.x(), draw_pos.y(), m_value_temp.c_str(),
-                      nullptr, text_bound);
+        nvgText(ctx, draw_pos.x(), draw_pos.y(),
+                value_or_mask_str(m_value_temp).c_str()
+                , nullptr);
+
+        nvgTextBounds(ctx, draw_pos.x(), draw_pos.y(),
+                      value_or_mask_str(m_value_temp).c_str()
+                      ,nullptr, text_bound);
 
         // recompute cursor positions
         nglyphs = nvgTextGlyphPositions(ctx, draw_pos.x(), draw_pos.y(),
-                m_value_temp.c_str(), nullptr, glyphs, max_glyphs);
+                                         value_or_mask_str(m_value_temp).c_str()
+                                        , nullptr, glyphs, max_glyphs);
 
         if (m_cursor_pos > -1) {
             if (m_selection_pos > -1) {
@@ -630,4 +641,16 @@ TextBox::SpinArea TextBox::spin_area(const Vector2i & pos) {
     return SpinArea::None;
 }
 
+void TextBox::set_password_field(bool enable, char mask) {
+    m_password = enable;
+    m_password_mask = mask;
+}
+
+std::string TextBox::value_or_mask_str(const std::string& str) const
+{
+    return m_password
+            ? std::string(str.length(), m_password_mask).c_str()
+            : str.c_str();
+}
+
 NAMESPACE_END(nanogui)