vault backup: 2023-04-17 11:58:20

.obsidian/workspace.json

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04. Programming/QT/timer.md

@@ -0,0 +1,19 @@
+使用QTimer來反覆執行工作。
+QTimer可以單次執行，也可以多次執行。
+
+使用概念如下：
+1. 建立 QTimer 物件，例如叫做 timer。
+2. 連接QTimer的timeout signal到你的反應 function
+3. 呼叫 timer->start()
+
+Example:
+```cpp
+QTimer* timer = new QTimer(this);
+connect(timer, SIGNAL(timeout()), this, SLOT(update()));
+timer->start(1000);
+```
+
+QTimer可以單次執行：
+```cpp
+QTimer::singleShot(200, this, SLOT(update());
+```