Flutter wait for async to finish

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In Flutter, you can use the “async” and “await” keywords to wait for an async function to finish and then continue with the execution of the rest of the code. The “await” keyword can only be used inside an async function.

Here’s an example explaining how to use “await” to wait for an async function to complete: 

    
async function someAsyncFunction() {
  print("Async function started");
  await Future.delayed(Duration(seconds: 2));  // Simulating some async task
  print("Async function completed");
}

void main() {
  print("Before calling async function");
  someAsyncFunction().then((_) {
    print("After async function completes");
  });
  print("After calling async function");
}

The above code demonstrates a simple Flutter application. In the “someAsyncFunction”, we use the “await” keyword to wait for a 2-second delay, simulating an async task. The function prints a message when it starts and completes.

In the “main” function, we print a message before calling the async function, call the async function using “await”, and print another message after the async function completes.

When running the above code, you will see the following output: 

    
Before calling async function
Async function started
After calling async function
Async function completed
After async function completes

As you can see, the code execution pauses at the “await” line inside the async function until the async task (delay) is completed. The rest of the code continues executing outside the async function.

You can apply the same concept in Flutter to wait for async tasks, such as API calls, database operations, or file operations, to complete before continuing with the execution of other parts of your code.

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