在Cordova+TypeScript+Webpack的Android应用中实现JS异步任务求助

Hey there! I totally get how async code can feel overwhelming at first—especially when you're juggling Cordova's plugin ecosystem, TypeScript, and Webpack. Let's break this down and get your getAllSMS function working asynchronously properly.

First: Rule Out Configuration Issues #

Let's start with the good news: your problem is almost certainly not related to TypeScript/Cordova/Webpack configuration—all three tools fully support Promises and async/await out of the box (as long as your TS config is set to target a modern enough ES version, which we'll touch on later). The issue is likely how you're structuring the async logic for your SMS function.

Step 1: Wrap Your Cordova Plugin Call in a Promise #

Most Cordova plugins use callback-based APIs, which is probably why you're confused. The fix is to wrap that callback logic into a Promise, which makes it easy to use async/await (the most readable way to handle async code these days).

Here's how to refactor your getAllSMS function:

// First, define a TypeScript interface for your SMS data to avoid "any" (optional but highly recommended)
interface SMSMessage {
  id: string;
  address: string;
  body: string;
  timestamp: number;
  // Add any other fields your plugin returns
}

function getAllSMS(): Promise<SMSMessage[]> {
  return new Promise((resolve, reject) => {
    // Call the Cordova SMS plugin's native method
    cordova.plugins.sms.getAllSMS(
      // Success callback: resolve the Promise with the SMS data
      (smsData: SMSMessage[]) => resolve(smsData),
      // Error callback: reject the Promise with an error message
      (error) => reject(new Error(`Failed to fetch SMS: ${error}`))
    );
  });
}

Step 2: Call the Function with Async/Await #

Now that getAllSMS returns a Promise, you can use async/await to wait for it to finish—no more nested callbacks!

Important note: You must always call Cordova plugins after the deviceready event fires—this is a common gotcha that makes it seem like your async code is broken when it's just timing.

// Create an async function to handle loading SMS data
async function loadAndProcessSMS() {
  try {
    // Wait for getAllSMS to finish and get the actual data
    const allSMS = await getAllSMS();
    
    // Now you can work with the SMS data (this runs after the async task completes)
    console.log("Fetched SMS count:", allSMS.length);
    // Update your UI, store the data, etc.
  } catch (error) {
    // Handle any errors (e.g., permission issues, plugin errors)
    console.error("Error loading SMS:", error);
    alert("Oops! Failed to load your SMS messages.");
  }
}

// Trigger the function only after Cordova is fully ready
document.addEventListener("deviceready", () => {
  loadAndProcessSMS();
});

Step 3: Double-Check Your TypeScript Config #

To make sure async/await works smoothly, verify your tsconfig.json has these settings (targeting ES2017 or newer supports async/await natively):

{
  "compilerOptions": {
    "target": "ES2017",
    "module": "ESNext",
    "lib": ["ES2017", "DOM"],
    "strict": true, // Optional but recommended for TypeScript
    // Other existing config...
  }
}

Webpack doesn't need special config for this—if you're using ts-loader or babel-loader, it will transpile the async code correctly for Android.

What If You Can't Use Async/Await? #

If for some reason you prefer the .then() syntax (e.g., working in a non-async context), you can use that too:

document.addEventListener("deviceready", () => {
  getAllSMS()
    .then((smsData) => {
      console.log("SMS data:", smsData);
    })
    .catch((error) => {
      console.error(error);
    });
});

Common Mistakes to Avoid #

• Calling plugins before deviceready: This will cause errors because Cordova hasn't initialized the plugin yet. Always wrap plugin calls in the deviceready event listener.
• Forgetting await: If you just write const sms = getAllSMS();, you'll get a Promise object instead of the actual SMS data—you need await to resolve it.
• Ignoring errors: Always use try/catch (or .catch()) to handle failures, like if the user denies SMS permissions.

内容的提问来源于stack exchange，提问作者neiya