try session.setCategory(AVAudioSessionCategoryPlayAndRecord, with: .mixWithOthers) 改为只从麦克风录音
时间: 2024-03-01 08:56:19 浏览: 103
将代码改为以下形式即可只从麦克风录音:
```
let session = AVAudioSession.sharedInstance()
do {
try session.setCategory(AVAudioSessionCategoryPlayAndRecord, with: .mixWithOthers)
try session.setMode(AVAudioSessionModeMeasurement)
try session.setPreferredSampleRate(44100)
try session.setInputGain(1.0)
let input = session.availableInputs!.first
try session.setPreferredInput(input)
} catch let error {
print(error.localizedDescription)
}
```
这里使用 `session.setPreferredInput` 将音频输入源设置为系统中可用的第一个音频输入源,通常是麦克风。
相关问题
Caused by: com.jcraft.jsch.JSchException: Session.connect: java.net.SocketException: Connection reset
根据提供的引用内容,你遇到的问题是`Caused by: com.jcraft.jsch.JSchException: Session.connect: java.net.SocketException: Connection reset`。这个错误通常是由于网络连接问题引起的。可能有以下几个原因导致这个错误:
1. 服务器端口未打开或被防火墙阻止:请确保你的SFTP服务器端口已正确打开,并且没有被防火墙阻止。
2. 服务器地址错误:请确保你的SFTP服务器地址是正确的,可以尝试使用ping命令来测试服务器的连通性。
3. 服务器连接超时:如果服务器连接超时,可能是由于网络延迟或服务器负载过高导致的。你可以尝试增加连接超时时间或者优化服务器性能。
4. 客户端配置错误:请确保你的Java代码中的SFTP配置是正确的,包括服务器地址、端口、用户名、密码等。
以下是一个示例代码,演示了如何使用JSch库进行SFTP上传文件:
```java
import com.jcraft.jsch.*;
public class SftpExample {
public static void main(String[] args) {
String host = "sftp.example.com";
int port = 22;
String username = "your-username";
String password = "your-password";
String localFilePath = "/path/to/local/file.txt";
String remoteFilePath = "/path/to/remote/file.txt";
try {
JSch jsch = new JSch();
Session session = jsch.getSession(username, host, port);
session.setPassword(password);
session.setConfig("StrictHostKeyChecking", "no");
session.connect();
ChannelSftp channel = (ChannelSftp) session.openChannel("sftp");
channel.connect();
channel.put(localFilePath, remoteFilePath);
channel.disconnect();
session.disconnect();
} catch (JSchException | SftpException e) {
e.printStackTrace();
}
}
}
```
with transaction.atomic():
`with transaction.atomic():` is a Python context manager that ensures that a group of database operations are executed as a single transaction. It's commonly used in Django web applications to ensure that database changes are atomic and consistent.
When `with transaction.atomic():` is used, all the database operations inside the block will either be committed together if all operations are successful, or rolled back if any operation fails. This is useful to maintain data integrity and consistency in the face of errors or exceptions.
For example, suppose you have a Django view that needs to update two models, `ModelA` and `ModelB`. You can use `with transaction.atomic():` to ensure that both updates are either committed or rolled back together:
```
from django.db import transaction
from myapp.models import ModelA, ModelB
@transaction.atomic
def my_view(request):
try:
a = ModelA.objects.get(id=1)
b = ModelB.objects.get(id=2)
a.field = 'new value'
b.field = 'new value'
a.save()
b.save()
except Exception as e:
# Handle exception
pass
```
In this example, if either `a.save()` or `b.save()` raises an exception, both updates will be rolled back and the database will remain unchanged.