我正在尝试为我的Windows应用商店应用创建一个计时器, 我已经能够更新secondes,但不是分钟, 分钟从组合框中获取其价值
我在这里做错了什么?
public sealed partial class MainPage : Page
{
int secCount = 0;
DispatcherTimer timerCount = new DispatcherTimer();
TextBlock time = new TextBlock();
int m;
public MainPage()
{
this.InitializeComponent();
timerCount.Interval = new TimeSpan(0, 0, 0, 1, 0);
timerCount.Tick += new EventHandler<object>(timer_tick);
m = Convert.ToInt32(cMinutes.SelectedValue);
}
private void timer_tick(object sender, object e)
{
time.Text = cHours.SelectedItem + ":" + m + ":" + secCount;
timer.Children.Add(time); //timer is the main grid
secCount--;
if(secCount < 0)
{
secCount = 59;
m--;
}
}
答案 0 :(得分:0)
首先,您的代码中存在一个问题,即您反复将TextBlock time
添加到timer
网格,并且您应该得到一个例外,抱怨TextBlock已经是Grid&#39之一小孩子。
您的问题的答案
您需要更新cMinutes&#39; SelectedValue或SelectedIndex。
一些增强功能:
我将字段timerCount
和time
的初始化移动到MainPage的构造函数中,最好在一个位置初始化所有字段。
由于int(secCount
和m
)默认为0,因此您无需为整数设置初始值。
public sealed partial class MainPage : Page
{
int secCount;
int m;
DispatcherTimer timerCount; //declare here, initialize in constructor
TextBlock time; //declare here, initialize in constructor
public MainPage()
{
this.InitializeComponent();
time = new TextBlock();
timer.Children.Add(time); //fix: only add ONCE
//populate the Combobox
cMinutes.Items.Add(0);
cMinutes.Items.Add(1);
cMinutes.Items.Add(2);
cMinutes.SelectedIndex = 2;
m = Convert.ToInt32(cMinutes.SelectedValue);
timerCount = new DispatcherTimer();
timerCount.Interval = new TimeSpan(0, 0, 0, 1, 0);
timerCount.Tick += new EventHandler<object>(timer_tick);
timerCount.Start();
}
private void timer_tick(object sender, object e)
{
time.Text = cHours.SelectedItem + ":" + m + ":" + secCount;
secCount--;
if (secCount < 0)
{
secCount = 59;
m--;
if (cMinutes.Items.Contains(m)) //fix: update Combobox's selected value
cMinutes.SelectedValue = m;
}
}
}