Xamarin.Android中AlertDialog点击确认后触发外部方法的实现

Got it, let's get this sorted for you! The main issue with your current code is that you're not properly triggering MyMethod() in the positive button's click handler, and you can simplify the dialog setup to make it cleaner. Here's how to adjust your code so that clicking "Yes" closes the dialog and runs your method right after:

Step-by-Step Fixed Code #

First, let's rewrite the dialog creation to be more straightforward, and ensure MyMethod() is called correctly:

// Call this method wherever you want to show the confirmation dialog (e.g., a button click)
private void ShowTransferConfirmationDialog()
{
    // Build the alert dialog
    AlertDialog.Builder alertBuilder = new AlertDialog.Builder(this);
    alertBuilder.SetMessage("Confirm transfer");

    // Handle "Yes" button click
    alertBuilder.SetPositiveButton("Yes", (sender, args) => 
    {
        // Close the dialog first
        ((AlertDialog)sender).Dismiss();
        // Now call your custom method
        MyMethod();
    });

    // Handle "No" button click
    alertBuilder.SetNegativeButton("No", (sender, args) => 
    {
        // Just close the dialog
        ((AlertDialog)sender).Dismiss();
    });

    // Create and show the dialog
    AlertDialog confirmDialog = alertBuilder.Create();
    confirmDialog.Show();
}

// Your existing method (make sure it's a member of MainActivity)
private void MyMethod()
{
    // Put your desired code here—this will run after clicking "Yes"
    Toast.MakeText(this, "Transfer confirmed! Executing MyMethod...", ToastLength.Short).Show();
}

Why This Works #

• Lambda Expressions: Using lambdas instead of delegates makes the code more readable, and lets you directly access the sender (which is the AlertDialog itself) to call Dismiss() to close it.
• Proper Method Call: By placing MyMethod() right after Dismiss(), the dialog closes first, then your method executes immediately after.
• Simplified Setup: You don't need a separate Dialog variable—using AlertDialog directly is cleaner and avoids confusion.

If You Prefer Using Delegates #

If you want to stick with the delegate syntax instead of lambdas, here's the adjusted version:

alertBuilder.SetPositiveButton("Yes", delegate(object sender, DialogClickEventArgs args) 
{
    ((AlertDialog)sender).Dismiss();
    MyMethod();
});

alertBuilder.SetNegativeButton("No", delegate(object sender, DialogClickEventArgs args) 
{
    ((AlertDialog)sender).Dismiss();
});

How to Trigger the Dialog #

Don't forget to call ShowTransferConfirmationDialog() from somewhere in your MainActivity, like a button click event:

// Example: Attach to a button's click handler
Button transferButton = FindViewById<Button>(Resource.Id.yourTransferButtonId);
transferButton.Click += (s, e) => ShowTransferConfirmationDialog();

That's it! Now when the user clicks "Yes", the dialog will close, and MyMethod() will run exactly as you want.

内容的提问来源于stack exchange，提问作者Profile2ForStack