良心推荐：优化你的App，实现安卓非媒体文件上传下载！

2023-09-04 22:20:06

1. 迈出第一步：理解文件上传与下载

在开始操作之前，让我们先了解一下文件上传和下载的概念。文件上传是指将文件从设备发送到服务器，而文件下载则是将文件从服务器传输到设备。在Android应用程序中，我们通常会使用HTTP请求来实现文件上传和下载。

2. 从头开始：建立Android应用程序

如果你还没有一个Android应用程序，现在就开始创建一个吧！打开Android Studio，创建一个新的项目，并选择“Empty Activity”作为模板。在你的项目中，创建一个名为“MainActivity”的Java类。这将是你的应用程序的主活动。

3. 准备就绪：添加文件选择器

为了让用户能够选择要上传的文件，我们需要添加一个文件选择器。你可以使用原生的文件路径选取api来实现这一点。在你的“MainActivity”类中，添加以下代码：

import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {
    private static final int FILE_SELECT_CODE = 1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button chooseFileButton = (Button) findViewById(R.id.choose_file_button);
        chooseFileButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
                intent.setType("*/*");
                startActivityForResult(intent, FILE_SELECT_CODE);
            }
        });
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == FILE_SELECT_CODE && resultCode == RESULT_OK) {
            Uri fileUri = data.getData();
            // Do something with the file
        }
    }
}

4. 挥洒创造力：构建文件上传功能

现在，我们已经有了文件选择器，接下来就让我们构建文件上传功能。可以使用uniapp文件上传api来实现这一点。在你的“MainActivity”类中，添加以下代码：

import com.alibaba.sdk.android.oss.OSS;
import com.alibaba.sdk.android.oss.OSSClient;
import com.alibaba.sdk.android.oss.common.auth.OSSCredentialProvider;
import com.alibaba.sdk.android.oss.common.auth.OSSStsTokenCredentialProvider;
import com.alibaba.sdk.android.oss.model.PutObjectRequest;

public class MainActivity extends AppCompatActivity {

    private OSS ossClient;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Initialize the OSS client
        OSSCredentialProvider credentialProvider = new OSSStsTokenCredentialProvider("<your-access-key-id>", "<your-access-key-secret>", "<your-security-token>");
        ossClient = new OSSClient(this, "<your-endpoint>", credentialProvider);

        // Handle the file upload
        Button uploadFileButton = (Button) findViewById(R.id.upload_file_button);
        uploadFileButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // Get the file path from the file selector
                Uri fileUri = Uri.parse("file:///storage/emulated/0/Download/file.txt");

                // Upload the file to OSS
                PutObjectRequest putObjectRequest = new PutObjectRequest("<your-bucket-name>", "file.txt", fileUri.getPath());
                ossClient.asyncPutObject(putObjectRequest, new OSSAsyncTaskHandler<PutObjectRequest, PutObjectResult>() {
                    @Override
                    public void onSuccess(PutObjectRequest request, PutObjectResult result) {
                        // Handle the upload success
                    }

                    @Override
                    public void onFailure(PutObjectRequest request, ClientException clientException, ServiceException serviceException) {
                        // Handle the upload failure
                    }
                });
            }
        });
    }
}

5. 锦上添花：实现文件下载功能

最后，让我们实现文件下载功能。同样可以使用uniapp文件下载api来实现这一点。在你的“MainActivity”类中，添加以下代码：

import com.alibaba.sdk.android.oss.OSS;
import com.alibaba.sdk.android.oss.OSSClient;
import com.alibaba.sdk.android.oss.common.auth.OSSCredentialProvider;
import com.alibaba.sdk.android.oss.common.auth.OSSStsTokenCredentialProvider;
import com.alibaba.sdk.android.oss.model.GetObjectRequest;

public class MainActivity extends AppCompatActivity {

    private OSS ossClient;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Initialize the OSS client
        OSSCredentialProvider credentialProvider = new OSSStsTokenCredentialProvider("<your-access-key-id>", "<your-access-key-secret>", "<your-security-token>");
        ossClient = new OSSClient(this, "<your-endpoint>", credentialProvider);

        // Handle the file download
        Button downloadFileButton = (Button) findViewById(R.id.download_file_button);
        downloadFileButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // Get the file path where the file will be downloaded
                String filePath = "/storage/emulated/0/Download/file.txt";

                // Download the file from OSS
                GetObjectRequest getObjectRequest = new GetObjectRequest("<your-bucket-name>", "file.txt");
                ossClient.asyncGetObject(getObjectRequest, filePath, new OSSAsyncTaskHandler<GetObjectRequest, GetObjectResult>() {
                    @Override
                    public void onSuccess(GetObjectRequest request, GetObjectResult result) {
                        // Handle the download success
                    }

                    @Override
                    public void onFailure(GetObjectRequest request, ClientException clientException, ServiceException serviceException) {
                        // Handle the download failure
                    }
                });
            }
        });
    }
}