deveco studio实现 ### 1. 简易天气预报应用 **技术点**： - **ArkUI框架**：用于构建用户界面。 - **HTTP API请求**：用于从天气服务提供商获取数据。 -

好的,我来为您介绍如何使用DevEco Studio实现一个简易的天气预报应用。

### 1. 准备工作

首先,确保您已经安装了DevEco Studio和相关的SDK。

### 2. 创建新项目

打开DevEco Studio,选择"Create New Project",然后选择"Empty Ability"模板。

### 3. 设计用户界面

使用ArkUI框架来构建用户界面。在`resources/base/layout`目录下找到`ability_main.xml`文件,并修改如下:

<?xml version="1.0" encoding="utf-8"?>
<DirectionalLayout
    xmlns:ohos="http://schemas.huawei.com/res/ohos"
    ohos:orientation="vertical"
    ohos:width="match_parent"
    ohos:height="match_parent"
    ohos:padding="16vp">

    <Text
        ohos:id="$+id/cityText"
        ohos:text="City"
        ohos:textSize="24vp"
        ohos:layout_width="match_parent"
        ohos:layout_height="wrap_content"/>

    <Text
        ohos:id="$+id/weatherText"
        ohos:text="Weather"
        ohos:textSize="18vp"
        ohos:layout_width="match_parent"
        ohos:layout_height="wrap_content"/>

    <Button
        ohos:id="$+id/refreshButton"
        ohos:text="Refresh"
        ohos:layout_width="match_parent"
        ohos:layout_height="wrap_content"/>
</DirectionalLayout>

### 4. 实现逻辑

在`MainAbilitySlice.java`文件中添加以下代码:

import ohos.aafwk.ability.AbilitySlice;
import ohos.aafwk.content.Intent;
import ohos.agp.components.Button;
import ohos.agp.components.Text;
import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
import org.json.JSONObject;
import java.io.IOException;

public class MainAbilitySlice extends AbilitySlice {
    private Text cityText;
    private Text weatherText;
    private Button refreshButton;

    @Override
    public void onStart(Intent intent) {
        super.onStart(intent);
        super.setUIContent(ResourceTable.Layout_ability_main);

        cityText = (Text) findComponentById(ResourceTable.Id_cityText);
        weatherText = (Text) findComponentById(ResourceTable.Id_weatherText);
        refreshButton = (Button) findComponentById(ResourceTable.Id_refreshButton);

        refreshButton.setClickedListener(component -> fetchWeatherData());

        fetchWeatherData();
    }

    private void fetchWeatherData() {
        OkHttpClient client = new OkHttpClient();
        Request request = new Request.Builder()
                .url("https://api.openweathermap.org/data/2.5/weather?q=Beijing&appid=YOUR_API_KEY")
                .build();

        client.newCall(request).enqueue(new Callback() {
            @Override
            public void onFailure(Call call, IOException e) {
                runOnUiThread(() -> weatherText.setText("Failed to load weather data"));
            }

            @Override
            public void onResponse(Call call, Response response) throws IOException {
                if (response.isSuccessful()) {
                    try {
                        JSONObject json = new JSONObject(response.body().string());
                        String weather = json.getJSONArray("weather").getJSONObject(0).getString("description");
                        runOnUiThread(() -> weatherText.setText(weather));
                    } catch (Exception e) {
                        runOnUiThread(() -> weatherText.setText("Error parsing weather data"));
                    }
                } else {
                    runOnUiThread(() -> weatherText.setText("Failed to load weather data"));
                }
            }
        });
    }
}

### 5. 添加网络权限

在`config.json`文件中添加网络权限:

{
  "module": {
    ...
    "reqPermissions": [
      {
        "name": "ohos.permission.INTERNET"
      }
    ],
    ...
  },
  ...
}

### 6. 运行应用

连接一台华为设备或使用模拟器,点击运行按钮即可。

这样,您就完成了一个简易的天气预报应用。这个应用使用了ArkUI框架来构建用户界面,并使用OkHttp库来发送HTTP请求获取天气数据。