Android客戶端與Python服務器端的簡單通信

最近在做一個APP，需要與服務器通信，一點一點的嘗試，記錄一下。

本文使用了OkHttp和Flask框架。

參考博文：https://ai-exception.com/2018/06/13/%E4%BD%BF%E7%94%A8python%E6%90%AD%E5%BB%BA%E6%9C%8D%E5%8A%A1%E5%99%A8%E5%B9%B6%E5%AE%9E%E7%8E%B0Android%E7%AB%AF%E4%B8%8E%E4%B9%8B%E9%80%9A%E4%BF%A1/

Android客戶端：

實現功能輸入完點擊OK按鈕后會toast成功的信息。

 

 Python服務端：

 

 各部分代碼如下：

activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <EditText
        android:id="@+id/username"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:hint="username" />

    <EditText
        android:id="@+id/password"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:hint="password" />

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:layout_marginTop="10dp"
        android:id="@+id/ok"
        android:text="ok" />

</LinearLayout>

為了使用OkHttp，需要在build.gradle中添加：implementation 'com.squareup.okhttp3:okhttp:3.11.0'

MainActivity.java:

package com.example.vesper.userpwd;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import java.io.IOException;

import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.FormBody;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;

public class MainActivity extends AppCompatActivity {

    private Button ok;
    private EditText username;
    private EditText password;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ok = findViewById(R.id.ok);
        username = findViewById(R.id.username);
        password = findViewById(R.id.password);


        ok.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String name = String.valueOf(username.getText());
                String pass = String.valueOf(password.getText());
                String url = "http://192.168.xxx.xxx:5000/register";//替換成自己的服務器地址
                SendMessage(url, name, pass);
            }
        });
    }


    private void SendMessage(String url, final String userName, String passWord) {
        OkHttpClient client = new OkHttpClient();
        FormBody.Builder formBuilder = new FormBody.Builder();
        formBuilder.add("username", userName);
        formBuilder.add("password", passWord);
        Request request = new Request.Builder().url(url).post(formBuilder.build()).build();
        Call call = client.newCall(request);
        call.enqueue(new Callback() {
            @Override
            public void onFailure(Call call, IOException e) {
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        runOnUiThread(new Runnable() {
                            @Override
                            public void run() {
                                Toast.makeText(MainActivity.this, "服務器錯誤", Toast.LENGTH_SHORT).show();
                            }
                        });
                    }
                });
            }

            @Override
            public void onResponse(Call call, final Response response) throws IOException {
                final String res = response.body().string();
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        if (res.equals("0")) {
                            runOnUiThread(new Runnable() {
                                @Override
                                public void run() {
                                    Toast.makeText(MainActivity.this, "該用戶名已被注冊", Toast.LENGTH_SHORT).show();
                                }
                            });
                        } else {
                            runOnUiThread(new Runnable() {
                                @Override
                                public void run() {
                                    Toast.makeText(MainActivity.this, "成功", Toast.LENGTH_SHORT).show();
                                }
                            });

                        }

                    }
                });
            }
        });

    }
}

 

 服務器端：userpwd.py:

from flask import Flask
from flask import request
import os

app = Flask(__name__)

@app.route('/')
def test():
    return '服務器正常運行'



#此方法處理用戶注冊
@app.route('/register',methods=['POST'])
def register():
    username=request.form['username']
    password=request.form['password']

    print('username:'+username)
    print('password:'+password)
    return '注冊成功'

if __name__ == '__main__':
    app.run(host='0.0.0.0')

遇到的問題：

1.一開始總是通信不上，提示服務器錯誤，原來是因為沒有增加一條權限：<uses-permission android:name="android.permission.INTERNET"/>