Edittext在android中的oncreate中获取空值

Question

- (AWSTask *)initializeClients:(NSDictionary *)logins {

NSLog(@"initializing clients...");

[AWSLogger defaultLogger].logLevel = AWSLogLevelError; //AWSLogLevelVerbose;
[AWSServiceConfiguration addGlobalUserAgentProductToken:AWS_MOBILEHUB_USER_AGENT];

NSString *email = [JNKeychain loadValueForKey:@"email"]; 
NSDictionary *logins = [NSDictionary dictionaryWithObject:email forKey:developerProvider];

    id<AWSCognitoIdentityProvider> identityProvider = [[CBDeveloperAuthenticatedIdentityProvider alloc]
                                                       initWithRegionType:AMAZON_COGNITO_REGION
                                                       identityId:nil
                                                       identityPoolId:AMAZON_COGNITO_IDENTITY_POOL_ID
                                                       logins:logins
                                                       providerName:developerProvider];


    self.credentialsProvider = [[AWSCognitoCredentialsProvider alloc]
                                initWithRegionType:AMAZON_COGNITO_REGION
                                identityProvider:identityProvider
                                unauthRoleArn:nil
                                authRoleArn:nil];

   //I have AWS_COGNITO_UNAUTH_ROLE and AWS_COGNITO_AUTH_ROLE but the docs don't seem to use them... and when I do there is no change
   //http://docs.aws.amazon.com/cognito/latest/developerguide/developer-authenticated-identities.html





AWSServiceConfiguration *configuration = [[AWSServiceConfiguration alloc] initWithRegion:AMAZON_COGNITO_REGION
                                                                     credentialsProvider:self.credentialsProvider];

[AWSServiceManager defaultServiceManager].defaultServiceConfiguration = configuration;


return [self.credentialsProvider getIdentityId];
}

字符串EditText edituname = (EditText) findViewById(R.id.username); EditText editpassword = (EditText) findViewById(R.id.password); String s1 = edituname.getText().toString(); String s2 = editpassword.getText().toString(); Toast.makeText(Main2Activity.this, s1, Toast.LENGTH_LONG).show(); 显示空值，因为代码位于s1方法内。我希望它在onCreate而非onCreate。所以请告诉我一个解决方案，以便在buttonclick中获得EditText的价值。

Answer 1

The value of edittext will be null at the time of initialization thats why it is null. If you want the value without any button click you can set TextWatcher的纯文本电子邮件