NoHttp封装--05 文件下载

xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical" >

    <ProgressBar
        android:id="@+id/pb_progress"
        style="?android:attr/progressBarStyleHorizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="10dp" />

    <TextView
        android:id="@+id/tv_result"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

    <Button
        android:id="@+id/btn_start_download"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:text="下载" />

</LinearLayout>

java:

import com.yolanda.nohttp.Headers;
import com.yolanda.nohttp.NoHttp;
import com.yolanda.nohttp.download.DownloadListener;
import com.yolanda.nohttp.download.DownloadRequest;
import com.yolanda.nohttp.error.ArgumentError;
import com.yolanda.nohttp.error.ClientError;
import com.yolanda.nohttp.error.NetworkError;
import com.yolanda.nohttp.error.ServerError;
import com.yolanda.nohttp.error.StorageReadWriteError;
import com.yolanda.nohttp.error.StorageSpaceNotEnoughError;
import com.yolanda.nohttp.error.TimeoutError;
import com.yolanda.nohttp.error.URLError;
import com.yolanda.nohttp.error.UnKnownHostError;
import com.yolanda.nohttp5.R;
import com.yolanda.nohttp5.config.AppConfig;
import com.yolanda.nohttp5.nohttp.CallServer;
import com.yolanda.nohttp5.util.Toast;

import android.app.Activity;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.widget.ProgressBar;
import android.widget.TextView;

public class DownloadActivity extends Activity implements View.OnClickListener, DownloadListener {

    private final static String PROGRESS_KEY = "download_progress";
    /**
     * 下载按钮、暂停、开始等.
     */
    private TextView mBtnStart;
    /**
     * 下载状态.
     */
    private TextView mTvResult;
    /**
     * 下载进度条.
     */
    private ProgressBar mProgressBar;
    /***
     * 下载地址.
     */
    private String url = "http://m.apk.67mo.com/apk/999129_21769077_1443483983292.apk";
    /**
     * 下载请求.
     */
    private DownloadRequest downloadRequest;

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

        mProgressBar = (ProgressBar) findViewById(R.id.pb_progress);
        mBtnStart = (TextView) findViewById(R.id.btn_start_download);
        mTvResult = (TextView) findViewById(R.id.tv_result);
        mBtnStart.setOnClickListener(this);

        // url 下载地址
        // fileFolder 保存的文件夹
        // fileName 文件名
        // isRange 是否断点续传下载
        // isDeleteOld 如果发现文件已经存在是否删除后重新下载
        String path = Environment.getExternalStorageDirectory().getAbsolutePath();
        downloadRequest = NoHttp.createDownloadRequest(url, path, "nohttp.apk", true, false);

        // 检查已经下载了一半的文件是什么状态
        int status = downloadRequest.checkBeforeStatus();
        if (status == DownloadRequest.STATUS_FINISH) {// 文件已经下载完成
            mTvResult.setText("下载完成");
            mBtnStart.setText("已经下载完成");
            // ... 提示用户安装apk
        } else if (status == DownloadRequest.STATUS_RESTART) {// 代表文件不存在，需要从头下载
            mTvResult.setText("");
            mBtnStart.setText("下载");
        } else if (status == DownloadRequest.STATUS_RESUME) {// 代表文件已经下载了一半了
            int progress = AppConfig.getInstance().getInt(PROGRESS_KEY, 0);
            mProgressBar.setProgress(progress);
            mTvResult.setText("已经下载了 " + progress + "%");
            mBtnStart.setText("继续下载");
        }
    }

    @Override
    public void onClick(View v) {
        if (downloadRequest.isStarted()) {
            // 暂停下载
            downloadRequest.cancel(true);
        } else {
            // what 区分下载
            // downloadRequest 下载请求对象
            // downloadListener 下载监听
            CallServer.getDownloadInstance().add(0, downloadRequest, this);
        }
    }

    /**
     * @param what 代表哪一个下载
     * @param isResume 是不是断点续续传开始下载的
     * @param beforeLenght 断点开始的地方的文件大小
     * @param headers 本地请求的时候的响应头
     * @param allCount 本次需要下载多少
     */
    @Override
    public void onStart(int what, boolean isResume, long beforeLenght, Headers headers, long allCount) {
        int progress = AppConfig.getInstance().getInt(PROGRESS_KEY, 0);
        mTvResult.setText("已下载: " + progress + "%");
        mBtnStart.setText("暂停");
    }

    @Override
    public void onProgress(int what, int progress, long fileCount) {
        AppConfig.getInstance().putInt(PROGRESS_KEY, progress);
        mProgressBar.setProgress(progress);
        mTvResult.setText("已经下载了 " + progress + "%");
    }

    @Override
    public void onDownloadError(int what, Exception exception) {
        mBtnStart.setText("再次尝试");

        String message = "下载出错了：";
        if (exception instanceof ClientError) {
            message += "客户端错误";
        } else if (exception instanceof ServerError) {
            message += "服务器发生内部错误";
        } else if (exception instanceof NetworkError) {
            message += "网络不可用，请检查网络";
        } else if (exception instanceof StorageReadWriteError) {
            message += "存储卡错误，请检查存储卡";
        } else if (exception instanceof StorageSpaceNotEnoughError) {
            message += "存储位置空间不足";
        } else if (exception instanceof TimeoutError) {
            message += "下载超时";
        } else if (exception instanceof UnKnownHostError) {
            message += "服务器找不到";
        } else if (exception instanceof URLError) {
            message += "url地址错误";
        } else if (exception instanceof ArgumentError) {
            message += "下载参数错误";
        } else {
            message += "未知错误";
        }
        mTvResult.setText(message);
    }

    @Override
    public void onFinish(int what, String filePath) {
        Toast.show("下载完成");
        mTvResult.setText("下载完成，文件保存在：" + filePath);
    }

    @Override
    public void onCancel(int what) {
        mTvResult.setText("下载暂停");
        mBtnStart.setText("继续下载");
    }

}