android 通过代码设置drawableLeft

/**
     * 
     * @desc 设置左边图标
     * @param @param drw
     * @return void
     */
    public void setAlertLeftIcon(Drawable drw){
        drw.setBounds(0, 0, drw.getMinimumWidth(), drw.getMinimumHeight());  
        alertTitle.setCompoundDrawables(drw, null, null, null);
    }