启动活动时应用程序崩溃

Question

我有一个 webview 应用程序，并且想在 url 中存在特定文本时从内部更新应用程序。

我在 webview 的 shouldOverrideUrlLoading 函数中调用这些：

Intent intent = new Intent(getApplicationContext(), Update.class);
startActivity(intent);
return true;

这里是 Update.class

public class Update extends MainActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        DownloadManager dm = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);
        String destination = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS) + "/";
        String fileName = "app-file.apk";
        destination += fileName;
        final Uri uri = Uri.parse("file://" + destination);

        File file = new File(destination);
        if (file.exists())
            file.delete();

        DownloadManager.Request request = new DownloadManager.Request(
                Uri.parse(getIntent().getStringExtra("http://example.com/app-file.apk")));
        request.setDestinationUri(uri);
        dm.enqueue(request);

        final String finalDestination = destination;
        final BroadcastReceiver onComplete = new BroadcastReceiver() {
            public void onReceive(Context ctxt, Intent intent) {
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
                    Uri contentUri = FileProvider.getUriForFile(ctxt, BuildConfig.APPLICATION_ID + ".provider", new File(finalDestination));
                    Intent openFileIntent = new Intent(Intent.ACTION_VIEW);
                    openFileIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
                    openFileIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                    openFileIntent.setData(contentUri);
                    startActivity(openFileIntent);
                    unregisterReceiver(this);
                    finish();
                } else {
                    Intent install = new Intent(Intent.ACTION_VIEW);
                    install.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                    install.setDataAndType(uri, "application/vnd.android.package-archive");
                    startActivity(install);
                    unregisterReceiver(this);
                    finish();
                }
            }
        };
        registerReceiver(onComplete, new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE));
    }
}

当我转到某个 url 启动活动时，应用程序崩溃。我很想看到任何解决方案。谢谢！！

我解决了，是权限错误。

Answer 1

我建议您查看 ADB Logcat，这将帮助您解决问题。 否则，请检查崩溃日志或确保您已在 manifest.xml 中声明了更新活动

Answer 2

确保在 Android Manifest.xml 中声明新活动

尝试改变这个

      Intent intent = new Intent(getApplicationContext(), Update.class);
      startActivity(intent);
      return true;

到这里

 Intent intent = new Intent(getApplicationContext(), Update.class);
 startActivity(intent);
 finish();
 return true;

让我知道这是怎么回事。