13.单选框UIRadioButton类

UIRadioButton和CheckBox的唯一区别是左侧图像不同，所以只需从CheckBox继承即可，只不过在构造函数中需要改变使用的图像。

单选框使用的图像如下：

单选框代码非常简单：

namespace StunEngine.SceneNodes.UI
...{
    /**//// <summary>
    /// 单选框控件
    /// </summary>
    public class UIRadioButton:UICheckBox 
    ...{
        /**//// <summary>
        /// 创建一个单选框控件
        /// </summary>
        public UIRadioButton(StunXnaGE engine, Scene setScene)
            : base(engine, setScene,"RadioButton", "Textures/UI/UIRadioButton")
        ...{ }
    }
}

但在实际应用中，单选框通常都是成组应用的，所以需要新建一个RadiuButtonGroup类，用以管理多个RadiuButton。

RadiuButtonGroup类的主要功能是：

• 依次排列每个radioButton；
• 当选择其中一个radioButton时要将它的Checked属性设为true，将其余的radioButton的Checked属性设为false，并引发ChangeSelection事件。

RadiuButtonGroup类代码如下：

namespace StunEngine.SceneNodes.UI
...{
    /**//// <summary>
    /// radioButton组
    /// </summary>
    public  class UIRadioButtonGroup:UISceneNode
    ...{
        /**//// <summary>
        /// 单选框数组
        /// </summary>
        UIRadioButton[] radioButtons;

        /**//// <summary>
        /// 各radioButton之间的垂直间距。
        /// </summary>
        float verticalSpace = 10.0f;        

        /**//// <summary>
        /// 被选中的单选框索引，初始时为-1，即没有单选框被选中。
        /// </summary>
        int selectedIndex = -1;       

        /**//// <summary>
        /// 创建一组单选框
        /// </summary>        
        /// <param name="engine">引擎</param>
        /// <param name="setScene">控件所属的scene</param>
        /// <param name="setPosition">2D屏幕位置</param>
        /// <param name="radiobutton">单选框数组</param>
        public UIRadioButtonGroup(StunXnaGE engine, Scene setScene, Vector2 setPosition, UIRadioButton[] radiobuttons)
            : base(engine,setScene ,setPosition ,null)
        ...{
            //UIRadioButtonGroup没有焦点
            this.TabStop = false;
            
            this.radioButtons = radiobuttons;
            
            //向下依次放置各个radioButton
            float radioButtonY = 0;            
            for (int i = 0; i < radiobuttons.Length; i++)
            ...{
                radiobuttons[i].CheckedChanged+=new EventHandler(OnCheckedChanged);
                radiobuttons[i].CanUncheck = false;
                if (radiobuttons[i].Checked  == true)
                    selectedIndex = i;                
                
                radiobuttons[i].Position =new Vector2 (setPosition.X, setPosition.Y + radioButtonY);
                radioButtonY += radiobuttons[i].Size.Y + verticalSpace;                
            }
            
        }        

        属性#region 属性     

        /**//// <summary>
        /// 获取或设置各radioButton之间的垂直间距，当此间距发生改变时需要重新调整各radioButton的位置。
        /// </summary>
        public float VerticalSpace
        ...{
            get ...{ return verticalSpace; }
            set
            ...{
                verticalSpace = value;
                ResetRadioButtons();
            }
        }

        /**//// <summary>
        /// 获取或设置被选中的单选框，返回选中单选框上的文字，或根据设置的文字选中单选框
        /// </summary>
        public string Selected
        ...{
            get
            ...{
                //遍历单选框数组
                for (int i = 0; i < radioButtons.Length; i++)
                    //如果找到第一个为选中状态的单选框，则返回这个单选框的文字
                    if (radioButtons[i].Checked == true)
                        return radioButtons[i].Text;
                //否则返回""
                return "";
            }
            set
            ...{
                //遍历单选框数组
                for (int i = 0; i < radioButtons.Length; i++)
                    //如果单选框的文字为设定的文字，则将这个单选框的Checked属性设为true
                    if (radioButtons[i].Text.ToLower() == value.ToLower())
                        radioButtons[i].Checked = true;
                    //将其他单选框的Checked设为false
                    else
                        radioButtons[i].Checked = false;
            }
        }

        #endregion

        事件相关处理程序#region 事件相关处理程序

        /**//// <summary>
        /// 选中项改变时引发的事件
        /// </summary>
        public event EventHandler ChangeSelection;

        /**//// <summary>
        /// 选中项改变时引发的事件的处理程序
        /// </summary>
        private void OnCheckedChanged(object obj, EventArgs e)
        ...{
            UIRadioButton radiobutton = (UIRadioButton)obj;            
            //将选中的单选框索引重置为-1
            int checkIndex = -1;
            
            //遍历单选框数组找到选中的单选框的索引
            for (int i = 0; i < this.radioButtons.Length; i++)
            ...{
                if (this.radioButtons[i] == radiobutton)
                ...{
                    checkIndex = i;                    
                    break;
                }
            }

            //如果当前被选中的单选框索引不等于前面选中的单选框索引，则引发ChangeSelection事件
            if(checkIndex != selectedIndex)
                if (ChangeSelection != null)
                    ChangeSelection(radiobutton.Text, null);

            //重新设置选中的单选框索引
            selectedIndex = checkIndex;
            //将其余单选框的Checked属性设为false
            for (int i = 0; i < this.radioButtons.Length; i++)
                if (i != checkIndex)
                    this.radioButtons[i].Checked  = false;
        }

        /**//// <summary>
        /// 如果2D位置发生改变则重新放置各radioButton的位置
        /// </summary>
        protected override void OnLocationChanged()
        ...{
            ResetRadioButtons();
            base.OnLocationChanged();
        }

        /**//// <summary>
        /// 切换每个radioButton的IsVisible属性
        /// </summary>
        /// <param name="e"></param>
        protected override void OnVisibleChanged(EventArgs e)
        ...{
            for (int i = 0; i < radioButtons.Length; i++)
                radioButtons[i].IsVisible = !radioButtons[i].IsVisible;
            base.OnVisibleChanged(e);
        }

        /**//// <summary>
        /// 重新设置每个单选框的位置
        /// </summary>
        private void ResetRadioButtons()
        ...{
            //将radioButton的竖直位置初始化为0            
            float radioButtonY = 0;

            for (int i = 0; i < this.radioButtons.Length; i++)
            ...{
                //向下依次放置各个radioButton
                radioButtons[i].Position = new Vector2(position.X, position.Y + radioButtonY);
                radioButtonY += radioButtons[i].Size.Y + verticalSpace;
            }
        }
        
        #endregion

        单元测试#region 单元测试

#if DEBUG
        /**//// <summary>
        /// 测试UIRadioButtonGroup类
        /// </summary>
        public static void TestUIRadioButtonGroup()
        ...{
            UIRadioButton[] radioButtons = null;
            UIRadioButtonGroup radioGroup=null;

            //显示相关信息
            UILabel lblMessage = null;

            TestGame.Start("测试UIRadioButtonGroup类，可按数字1，2，3键，Right、Down键，空格键",
                delegate
                ...{
                    radioButtons = new UIRadioButton[3];
                    
                    radioButtons[0]=new UIRadioButton(TestGame.engine, TestGame.scene);                    
                    radioButtons[0].Text = "First";
                    radioButtons[0].Checked = true;
                    TestGame.scene.AddNode(radioButtons [0]);

                    radioButtons[1] = new UIRadioButton(TestGame.engine, TestGame.scene);
                    radioButtons[1].Text = "Second";                    
                    TestGame.scene.AddNode(radioButtons[1]);

                    radioButtons[2] = new UIRadioButton(TestGame.engine, TestGame.scene);
                    radioButtons[2].Text = "Third";
                    TestGame.scene.AddNode(radioButtons[2]);                   


                    lblMessage = new UILabel(TestGame.engine, TestGame.scene);
                    lblMessage.Position = new Vector2(100, 250);
                    TestGame.scene.AddNode(lblMessage);

                    radioGroup = new UIRadioButtonGroup(TestGame.engine, TestGame.scene, new Vector2(100,100), radioButtons);                    

                    //关闭相机控制器
                    TestGame.scene.fpsCamCtrl.Enabled = false;
                },
                delegate
                ...{
                    //显示被选中的单选框上的文字
                    lblMessage.Text = "You Select RadioButton:"+radioGroup.Selected;
                    
                    //按1，2，3切换选中的单选框
                    if (Input.KeyboardKeyJustPressed (Keys.D1 ))
                        radioGroup.Selected = "First";
                    if (Input.KeyboardKeyJustPressed(Keys.D2))
                        radioGroup.Selected = "Second";
                    if (Input.KeyboardKeyJustPressed(Keys.D3))
                        radioGroup.Selected = "Third";
                    
                    //按Right键移动控件
                    if (Input.KeyboardRightJustPressed)
                        radioGroup.Position += new Vector2(5, 5);
                    //按Downt键增加各radioButton间距
                    if (Input.KeyboardDownJustPressed)
                        radioGroup.VerticalSpace  += 2;
                    
                    //按空格键切换控件的显示与否
                    if(Input .KeyboardSpaceJustPressed )
                        radioGroup .IsVisible =!radioGroup .IsVisible ;
                }
                );
        }
#endif
        #endregion
    }
        
}

单元测试截图如下：

发布时间：2010/1/20 下午4:42:39  阅读次数：7017