pyqtgraph/graphicsItems/LabelItem.py

from pyqtgraph.Qt import QtGui, QtCore
import pyqtgraph.functions as fn
from GraphicsWidget import GraphicsWidget


__all__ = ['LabelItem']

class LabelItem(GraphicsWidget):
    """
    GraphicsWidget displaying text.
    Used mainly as axis labels, titles, etc.
    
    Note: To display text inside a scaled view (ViewBox, PlotWidget, etc) use TextItem
    """
    
    
    def __init__(self, text, parent=None, angle=0, **args):
        GraphicsWidget.__init__(self, parent)
        self.item = QtGui.QGraphicsTextItem(self)
        self.opts = args
        if 'color' not in args:
            self.opts['color'] = 'CCC'
        else:
            if isinstance(args['color'], QtGui.QColor):
                self.opts['color'] = fn.colorStr(args['color'])[:6]
        self.sizeHint = {}
        self.setText(text)
        self.setAngle(angle)
        
            
    def setAttr(self, attr, value):
        """Set default text properties. See setText() for accepted parameters."""
        self.opts[attr] = value
        
    def setText(self, text, **args):
        """Set the text and text properties in the label. Accepts optional arguments for auto-generating
        a CSS style string:
           color:   string (example: 'CCFF00')
           size:    string (example: '8pt')
           bold:    boolean
           italic:  boolean
           """
        self.text = text
        opts = self.opts.copy()
        for k in args:
            opts[k] = args[k]
        
        optlist = []
        if 'color' in opts:
            optlist.append('color: #' + opts['color'])
        if 'size' in opts:
            optlist.append('font-size: ' + opts['size'])
        if 'bold' in opts and opts['bold'] in [True, False]:
            optlist.append('font-weight: ' + {True:'bold', False:'normal'}[opts['bold']])
        if 'italic' in opts and opts['italic'] in [True, False]:
            optlist.append('font-style: ' + {True:'italic', False:'normal'}[opts['italic']])
        full = "<span style='%s'>%s</span>" % ('; '.join(optlist), text)
        #print full
        self.item.setHtml(full)
        self.updateMin()
        
    def resizeEvent(self, ev):
        c1 = self.boundingRect().center()
        c2 = self.item.mapToParent(self.item.boundingRect().center()) # + self.item.pos()
        dif = c1 - c2
        self.item.moveBy(dif.x(), dif.y())
        #print c1, c2, dif, self.item.pos()
        
    def setAngle(self, angle):
        self.angle = angle
        self.item.resetTransform()
        self.item.rotate(angle)
        self.updateMin()
        
    def updateMin(self):
        bounds = self.item.mapRectToParent(self.item.boundingRect())
        self.setMinimumWidth(bounds.width())
        self.setMinimumHeight(bounds.height())
        #print self.text, bounds.width(), bounds.height()
        
        #self.sizeHint = {
            #QtCore.Qt.MinimumSize: (bounds.width(), bounds.height()),
            #QtCore.Qt.PreferredSize: (bounds.width(), bounds.height()),
            #QtCore.Qt.MaximumSize: (bounds.width()*2, bounds.height()*2),
            #QtCore.Qt.MinimumDescent: (0, 0)  ##?? what is this?
        #}
            
        
    #def sizeHint(self, hint, constraint):
        #return self.sizeHint[hint]