无法从异步任务下载.apk文件

Question

我正在尝试从async任务中的URL下载apk，但是它无法正常工作，并且.apk不在这里或部分下载，我不知道为什么。 进度栏对话框未显示任何进度，并且停留在0。请帮助我解决此问题。

先感谢您！

这是我的代码：

public class MainActivity extends AppCompatActivity implements View.OnClickListener{

InterstitialAd mInterstitialAd;
ProgressDialog pDialog;

private Button downloadButton;

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

    pDialog = new ProgressDialog(this);
    downloadButton = (Button) findViewById(R.id.button_download);
    downloadButton.setOnClickListener(this);

    mInterstitialAd = new InterstitialAd(this);
    mInterstitialAd.setAdUnitId(getString(R.string.interstitial_full_screen));
    AdRequest adRequest = new AdRequest.Builder().build(); 
    mInterstitialAd.loadAd(adRequest);

    mInterstitialAd.setAdListener(new AdListener() {
        public void onAdLoaded() {
            showInterstitial();
        }
    });

}

private void showInterstitial() {
    if (mInterstitialAd.isLoaded()) {
        mInterstitialAd.show();
    }
}

@Override
public void onClick(View v) {
    switch (v.getId()){
        case R.id.button_download:
            DownloadAndInstall downloadAndInstall = new DownloadAndInstall();
            downloadAndInstall.execute("http://cygnus.androidapksfree.com/hulk/com.viber.voip_v6.0.2.22-226_Android-4.0.apk");
            break;
    }
}

class DownloadAndInstall extends AsyncTask<String, String, String> {

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog.setMessage("Downloading App");
        pDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
        pDialog.setIndeterminate(true);
        pDialog.setProgress(0);
        pDialog.show();
    }

    @Override
    protected String doInBackground(String... urlArr) {

        int count;
        try {
            Log.d("URL","URL = "+urlArr[0]);
            URL url = new URL(urlArr[0]);
            URLConnection urlConnection = url.openConnection();
            urlConnection.connect();

            int fileSize = urlConnection.getContentLength();
            File sdcard = Environment.getExternalStorageDirectory();

            InputStream input = new BufferedInputStream(url.openStream(), 8192);
            OutputStream output = new FileOutputStream(sdcard+"/app_file.apk");

            byte[] buffer = new byte[1024];
            float total = 0;

            while ((count = input.read(buffer)) != -1) {
                total += count;
                publishProgress(""+(int)((total*100)/fileSize));
                output.write(buffer, 0, count);
            }

            output.flush();
            output.close();
            input.close();

        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e){
            e.printStackTrace();
        }
        return null;
    }

    @Override
    protected void onProgressUpdate(String... progress) {
        pDialog.setProgress(Integer.parseInt(progress[0]));
    }

    @Override
    protected void onPostExecute(String file_url) {
        pDialog.dismiss();
    }
}

}

AndroidMenifest.xml

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="in.friper.rajeshincorp.abc">

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission
    android:name="android.permission.INSTALL_PACKAGES"
    tools:ignore="ProtectedPermissions"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_SYNC_SETTINGS" />

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">

    <meta-data
        android:name="com.google.android.gms.version"
        android:value="@integer/google_play_services_version" />

    <activity
        android:name=".SplashActivity"
        android:configChanges="orientation|keyboardHidden|screenSize"
        android:label="@string/app_name"
        android:theme="@style/FullscreenTheme">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

    <activity
        android:name="com.google.android.gms.ads.AdActivity"
        android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize"
        android:theme="@android:style/Theme.Translucent" />

    <activity
        android:name=".MainActivity"
        android:theme="@style/FullscreenTheme">

    </activity>
</application>

SplashActivity.java

public class SplashActivity extends AppCompatActivity {

private static final int MY_PERMISSIONS_REQUEST_READ_EXTERNAL_STORAGE = 123;
private static final int MY_PERMISSIONS_REQUEST_WRITE_SYNC_SETTINGS = 345;
private static final int MY_PERMISSIONS_REQUEST_ACCESS_NETWORK_STATE = 567;

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

    if(ContextCompat.checkSelfPermission(SplashActivity.this, Manifest.permission.READ_EXTERNAL_STORAGE)!= PackageManager.PERMISSION_GRANTED &&
            ContextCompat.checkSelfPermission(SplashActivity.this, Manifest.permission.WRITE_SYNC_SETTINGS)!= PackageManager.PERMISSION_GRANTED &&
            ContextCompat.checkSelfPermission(SplashActivity.this, Manifest.permission.ACCESS_NETWORK_STATE)!= PackageManager.PERMISSION_GRANTED) {

        if (ActivityCompat.shouldShowRequestPermissionRationale(SplashActivity.this, Manifest.permission.READ_EXTERNAL_STORAGE) &&
                ActivityCompat.shouldShowRequestPermissionRationale(SplashActivity.this, Manifest.permission.WRITE_SYNC_SETTINGS) &&
                ActivityCompat.shouldShowRequestPermissionRationale(SplashActivity.this, Manifest.permission.ACCESS_NETWORK_STATE)) {

            // Show an explanation to the user *asynchronously* -- don't block
            // this thread waiting for the user's response! After the user
            // sees the explanation, try again to request the permission.

        } else {

            // No explanation needed, we can request the permission.
            ActivityCompat.requestPermissions(SplashActivity.this,
                    new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},
                    MY_PERMISSIONS_REQUEST_READ_EXTERNAL_STORAGE);

            ActivityCompat.requestPermissions(SplashActivity.this,
                    new String[]{Manifest.permission.WRITE_SYNC_SETTINGS},
                    MY_PERMISSIONS_REQUEST_WRITE_SYNC_SETTINGS);

            ActivityCompat.requestPermissions(SplashActivity.this,
                    new String[]{Manifest.permission.ACCESS_NETWORK_STATE},
                    MY_PERMISSIONS_REQUEST_ACCESS_NETWORK_STATE);

        }
    }
    goToNextActivity();
}

@Override
public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
    switch (requestCode) {

        case MY_PERMISSIONS_REQUEST_READ_EXTERNAL_STORAGE: {

            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                // permission was granted
            } else {
                // permission denied
            }
            return;

        }

        case MY_PERMISSIONS_REQUEST_WRITE_SYNC_SETTINGS: {

            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                // permission was granted
            } else {
                // permission denied
            }
            return;
        }

        case MY_PERMISSIONS_REQUEST_ACCESS_NETWORK_STATE: {

            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                // permission was granted
            } else {
                // permission denied
            }
            return;
        }

    }

}

public void goToNextActivity(){
    Intent i= new Intent(this,MainActivity.class);
    startActivity(i);
    finish();
}

}

Answer 1

修复了从错误的线程调用的Toast之后，以上代码实际上可以正常工作。
由于apk太大，该百分比似乎停留在0上。