Question

我正在构建一个简单的usenet新闻阅读器（好吧，试图构建）。以下代码有效。从SharedPreferences获取用户名，主机，密码并连接到服务器并成功进行身份验证，但是它会锁定UI，直到完成所有任务。

我如何更改此代码，以便它不会锁定UI？

package com.webfoo.newz;

import java.io.IOException;
import java.net.SocketException;

import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import org.apache.commons.net.nntp.NNTPClient;

public class NewzActivity extends Activity {

TextView statusText;
String PREFS_NAME = "MyPrefsFile";
SharedPreferences settings;
NNTPClient nntpClient;
int port;
String username;
String password;
String host;


/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    this.statusText = (TextView)findViewById(R.id.connectionStatusTextView);
    this.nntpClient = new NNTPClient();
    this.settings = getSharedPreferences(PREFS_NAME, 0);
}

public void openSettings(View button){
    Intent settingsIntent = new Intent( NewzActivity.this, SettingsActivity.class );
    startActivity( settingsIntent );
}

public void makeConnection(View button) {

    this.statusText.setText("Connecting...");       
    this.port = settings.getInt("UsenetPort", 563);
    this.host = settings.getString("UsenetHost", "");
    this.nntpClient.setDefaultPort( port );
    this.nntpClient.setDefaultTimeout( 9999 );
    // this.nntpClient.setConnectTimeout( 9999 );
    this.statusText.setText("Connecting to " + host );

    try {
        this.nntpClient.connect( host );
    } catch (SocketException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

    this.statusText.setText("Connected to " + host );

    if( nntpClient.isConnected() ){
        setAuthDetails();
    }else{
        this.statusText.setText("Failed to Connected to " + host );
    }

}

private void setAuthDetails() {

    this.username = settings.getString("UsenetUsername", "");
    this.password = settings.getString("UsenetPassword", "");

    try {
        nntpClient.authinfoUser(username);
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    try {
        nntpClient.authinfoPass(password);
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

    statusText.setText("Authenticated as " + username );

}


}

Answer 1

查看AsyncTask

Answer 2

我相信一些Android专家会指出你想要用来实现这个的各种框架的方向，但基本问题如下。

用户界面是单线程的，该线程通常被称为事件调度线程。因此，当用户点击某个按钮并执行需要很长时间的操作时，会阻止UI同时执行任何其他操作。

您需要做的是在不同的线程中执行任何长时间运行的任务，并确保EDT线程和工作线程之间的通信是线程安全的。

Answer 3

Thread T = new Thread(new Runnable(){
    public void run(){
        ///////////////////////////////
        //YOUR CODE
        ///////////////////////////////
    }
});


        //IF YOU WANT TO MANIPULATE THE UI inside the run()
        //USE:
runOnUiThread(new Runnable() {
@Override
public void run() {
    ///////////////////////////////
    //Your Code
    ///////////////////////////////
    }
});

连接到Socket锁定UI

3 个答案: