android - 在 Android 后台服务中静默 Google 登录

Question

我正在我的 Android 应用程序中运行后台服务。我使用从登录 Activity 中获取的 IdToken 在后端服务器上进行身份验证。该服务以 START_STICKY 模式运行，因此即使应用程序关闭，该服务也会继续在后台运行以从后端服务器获取任何通知。我面临的问题是当 IdToken 过期时，我无法在服务本身中更新它。如果 token 已过期，回调函数不会收到任何结果。如果 token 还没有过期，它会立即得到结果。

这是 signIn 函数和 handleSignIn 函数的代码。

private void signIn() {
        new Thread(new Runnable() { public void run() {
        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestEmail()
                .requestIdToken("<My server_client_id>")
                .build();
        GoogleApiClient mGoogleApiClient = new GoogleApiClient.Builder(context)
                .addApi(Auth.GOOGLE_SIGN_IN_API, gso)
                .build();

        OptionalPendingResult<GoogleSignInResult> opr = Auth.GoogleSignInApi.silentSignIn
                (mGoogleApiClient);
        if (opr.isDone()) {
            // If the user's cached credentials are valid, the OptionalPendingResult will be "done"

            // and the GoogleSignInResult will be available instantly.
            Log.d(TAG, "Got cached sign-in");
            GoogleSignInResult result = opr.get();
            handleSignInResult(result);
        } else {
            // If the user has not previously signed in on this device or the sign-in has
            // expired,
            // this asynchronous branch will attempt to sign in the user silently.  Cross-device
            // single sign-on will occur in this branch.
            Log.d(TAG, "had to sign in again");
            opr.setResultCallback(new ResultCallback<GoogleSignInResult>() {
                @Override
                public void onResult(GoogleSignInResult googleSignInResult) {
                    Log.d(TAG, "got result");
                    handleSignInResult(googleSignInResult);
                }
            });
        }}}).start();
    }

Answer 1

尝试移动

opr.setResultCallback(new ResultCallback<GoogleSignInResult>() {
            @Override
            public void onResult(GoogleSignInResult googleSignInResult) {
                Log.d(TAG, "got result");
                handleSignInResult(googleSignInResult);
            }
        });

在其 if 语句之前。我知道谷歌文档说要按照你的方式使用它，我也这样做了，直到我意识到如果 ResultCallback 只在 else block 中初始化，在 opr 已经运行之后，它就永远不会被调用.

按照我的建议，你的代码应该是这样的:

private void signIn() {
    new Thread(new Runnable() { public void run() {
    GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
            .requestEmail()
            .requestIdToken("<My server_client_id>")
            .build();
    GoogleApiClient mGoogleApiClient = new GoogleApiClient.Builder(context)
            .addApi(Auth.GOOGLE_SIGN_IN_API, gso)
            .build();

    OptionalPendingResult<GoogleSignInResult> opr = Auth.GoogleSignInApi.silentSignIn
            (mGoogleApiClient);
    opr.setResultCallback(new ResultCallback<GoogleSignInResult>() {
            @Override
            public void onResult(GoogleSignInResult googleSignInResult) {
                Log.d(TAG, "got result");
                handleSignInResult(googleSignInResult);
            }
        });}}).start();
}