Add some layout support code to the new widget system and clean-up some code in it.

git-svn-id: svn+ssh://svn.gna.org/svn/warzone/trunk@4944 4a71c877-e1ca-e34f-864e-861f7616d084

lib/betawidget/vector.c

@@ -102,4 +102,3 @@ int vectorSize(vector *v)
 {
 	return v->head;
 }
-

lib/betawidget/widget.c

@@ -34,6 +34,13 @@ static void widgetInitVtbl(widget *self)
 		vtbl.enable				= widgetEnableImpl;
 		vtbl.disable			= widgetDisableImpl;
 		
+		vtbl.getMinSize			= widgetGetMinSizeImpl;
+		vtbl.getMaxSize			= widgetGetMaxSizeImpl;
+		
+		vtbl.setAlign			= widgetSetAlignImpl;
+		
+		vtbl.doLayout			= NULL;
+		
 		vtbl.doDraw		 		= NULL;
 		
 		vtbl.destroy			= widgetDestroyImpl;
@@ -108,7 +115,7 @@ static void widgetDrawChildren(widget *self, cairo_t *cr)
 	// Draw our children
 	for (i = 0; i < vectorSize(self->children); i++)
 	{
-		widget *child = WIDGET(vectorAt(self->children, i));
+		widget *child = vectorAt(self->children, i);
 		cairo_matrix_t current;
 		
 		// Translate such that (0,0) is the location of the widget
@@ -200,12 +207,25 @@ bool widgetAddChildImpl(widget *self, widget *child)
 	// Add the widget
 	vectorAdd(self->children, child);
 	
-	// FIXME: We need to do some arbitration
-	
-	// Set ourself as its parent
-	child->parent = self;
-	
-	return true;
+	// Re-layout ourself
+	if (widgetDoLayout(self))
+	{
+		// Set ourself as its parent
+		child->parent = self;
+		
+		return true;
+	}
+	// Not enough space to fit the widget
+	else
+	{
+		// Remove child
+		widgetRemoveChild(self, child);
+		
+		// Restore the layout
+		widgetDoLayout(self);
+		
+		return false;
+	}
 }
 
 /*
@@ -294,7 +314,7 @@ void widgetEnableImpl(widget *self)
 	// Enable all of our children
 	for (i = 0; i < vectorSize(self->children); i++)
 	{
-		widgetEnable(WIDGET(vectorAt(self->children, i)));
+		widgetEnable(vectorAt(self->children, i));
 	}
 }
 
@@ -380,6 +400,26 @@ void widgetBlurImpl(widget *self)
 	widgetFireCallbacks(self, &evt);
 }
 
+point widgetGetMinSizeImpl(widget *self)
+{
+	return self->minSize;
+}
+
+point widgetGetMaxSizeImpl(widget *self)
+{
+	return self->maxSize;
+}
+
+void widgetSetAlignImpl(widget *self, vAlign v, hAlign h)
+{
+	self->vAlignment = v;
+	self->hAlignment = h;
+	
+	// Re-align our children
+	// TODO: We should check the return value here
+	widgetDoLayout(self);
+}
+
 widget *widgetGetCurrentlyFocused(widget *self)
 {
 	int i;
@@ -495,11 +535,35 @@ void widgetBlur(widget *self)
 	WIDGET_GET_VTBL(self)->blur(self);
 }
 
+point widgetGetMinSize(widget *self)
+{
+	return WIDGET_GET_VTBL(self)->getMinSize(self);
+}
+
+point widgetGetMaxSize(widget *self)
+{
+	return WIDGET_GET_VTBL(self)->getMaxSize(self);
+}
+
+void widgetSetAlign(widget *self, vAlign v, hAlign h)
+{
+	WIDGET_GET_VTBL(self)->setAlign(self, v, h);
+}
+
 void widgetDoDraw(widget *self, cairo_t *cr)
 {
+	WIDGET_CHECK_METHOD(self, doDraw);
+
 	WIDGET_GET_VTBL(self)->doDraw(self, cr);
 }
 
+bool widgetDoLayout(widget *self)
+{
+	WIDGET_CHECK_METHOD(self, doLayout);
+
+	return WIDGET_GET_VTBL(self)->doLayout(self);
+}
+
 bool widgetHandleEvent(widget *self, event *evt)
 {
 	return WIDGET_GET_VTBL(self)->handleEvent(self, evt);

lib/betawidget/widget.h

@@ -1,6 +1,9 @@
 #ifndef WIDGET_H_
 #define WIDGET_H_
 
+// TODO: Make this cross platform (MSVC)
+#include <stdint.h>
+
 #include <cairo.h>
 
 #include "vector.h"
@@ -25,6 +28,9 @@ typedef bool (*callback)		(widget *widget, event *evt, void *userData);
 
 typedef struct _eventTableEntry eventTableEntry;
 
+typedef enum _hAlign			hAlign;
+typedef enum _vAlign			vAlign;
+
 /*
  * The valid event types
  */
@@ -140,7 +146,27 @@ struct _eventTableEntry
 };
 
 /*
- * The widget classes virtual method table.
+ * The possible horizontal sides a child can be aligned to
+ */
+enum _hAlign
+{
+	LEFT,
+	CENTRE,
+	RIGHT
+};
+
+/*
+ * The possible vertical sides a child can be aligned to
+ */
+enum _vAlign
+{
+	TOP,
+	MIDDLE,
+	BOTTOM
+};
+
+/*
+ * The widget classes virtual method table
  */
 struct _widgetVtbl
 {
@@ -160,7 +186,13 @@ struct _widgetVtbl
 	void	(*enable)				(widget *self);
 	void	(*disable)				(widget *self);
 	
+	point	(*getMinSize)			(widget *self);
+	point	(*getMaxSize)			(widget *self);
+	
+	void	(*setAlign)				(widget *self, vAlign v, hAlign h);
+	
 	void	(*doDraw)				(widget *self, cairo_t *cr);
+	bool	(*doLayout)				(widget *self);
 	
 	void	(*destroy)				(widget *self);
 };
@@ -190,6 +222,22 @@ struct _widget
 	 */
 	widget *parent;
 	
+	/*
+	 * The minimum size the widget can be
+	 */
+	point minSize;
+	
+	/*
+	 * The maximum size the widget can be
+	 */
+	point maxSize;
+	
+	/*
+	 * Child alignment
+	 */
+	vAlign vAlignment;
+	hAlign hAlignment; 
+	
 	//--------------------------------------
 	// Public members
 	//--------------------------------------
@@ -203,7 +251,7 @@ struct _widget
 	 * Arbitary user-defined data
 	 */
 	void *pUserData;
-	int userData;
+	int32_t userData;
 	
 	/*
 	 * The offset of the widget relative to its parent
@@ -236,6 +284,7 @@ struct _widget
  */
 #define WIDGET(self) ((widget *) (self))
 #define WIDGET_GET_VTBL(self) ((WIDGET(self))->vtbl)
+#define WIDGET_CHECK_METHOD(self, method) (assert(WIDGET_GET_VTBL(self)->method))
 
 /*
  * Protected methods
@@ -252,6 +301,10 @@ void widgetEnableImpl(widget *self);
 void widgetDisableImpl(widget *self);
 void widgetFocusImpl(widget *self);
 void widgetBlurImpl(widget *self);
+point widgetGetMinSizeImpl(widget *self);
+point widgetGetMaxSizeImpl(widget *self);
+void widgetSetAlignImpl(widget *self, vAlign v, hAlign h);
+void widgetDoAlignImpl(widget *self);
 
 bool widgetHandleEventImpl(widget *instance, event *evt);
 
@@ -297,8 +350,8 @@ widget *windgetGetRoot(widget *self);
 
 /**
  * Attempts to add child as a child widget of self. The exact location of the
- * widget (as well as its dimensions) are decided during an arbitration process
- * between the self and the child.
+ * widget (as well as its dimensions) are decided based off of the min & max
+ * sizes of the child.
  *
  * @param self	The widget to add the child widget to.
  * @param child	The widget to be added.
@@ -399,7 +452,7 @@ widget *widgetGetCurrentlyFocused(widget *self);
 void widgetFocus(widget *self);
 
 /**
-c * Blurs the current widget (removes keyboard focus from it). Before self is
+ * Blurs the current widget (removes keyboard focus from it). Before self is
  * blurred any child widget with focus is blurred first. Finally the EVT_BLUR
  * event handlers for self are fired.
  *
@@ -407,6 +460,33 @@ c * Blurs the current widget (removes keyboard focus from it). Before self is
  */
 void widgetBlur(widget *self);
 
+/**
+ * Returns the minimum size that the widget can be.
+ * 
+ * @param self	The widget to return the miniumum size of.
+ * @return The miniumum (x,y) size of the widget.
+ */
+point widgetGetMinSize(widget *self);
+
+/**
+ * Returns the maxiumum size that the widget can be. A value of -1 for either
+ * the x or y co-ordinate means that there is no maximum size.
+ *
+ * @param self	The widget to return the maximum size of.
+ * @return The maximum (x,y) size of the widget.
+ */
+point widgetGetMaxSize(widget *self);
+
+/**
+ * Sets the alignment of child widgets of self. This is used when the maximum
+ * size of the child widgets is less than that of the size of self.
+ * 
+ * @param self	The widget to set the alignment of.
+ * @param v		The vertical alignment of the widget (TOP, MIDDLE, BOTTOM).
+ * @param h		The horizontal alignment of the widget (LEFT, CENTRE, RIGHT).
+ */
+void widgetSetAlign(widget *self, vAlign v, hAlign h);
+
 /**
  * TODO
  */
@@ -426,6 +506,11 @@ bool widgetHandleEvent(widget *self, event *evt);
  */
 void widgetDoDraw(widget *self, cairo_t *cr);
 
+/**
+ *
+ */
+bool widgetDoLayout(widget *self);
+
 /**
  * Fires all of the event handlers registered for evt->type on the widger self.
  *
@@ -435,4 +520,3 @@ void widgetDoDraw(widget *self, cairo_t *cr);
 bool widgetFireCallbacks(widget *self, event *evt);
 
 #endif /*WIDGET_H_*/
-