Question

问候爱好者的编程！

我在调用外部类时遇到问题，我用过：

AutoUpdate shh = new AutoUpdate();
shh;

但是，我无法通过 MainActivity 调用该课程。

目前我正在调用该类，好像它是另一个活动（但事实并非如此，该类所做的是验证是否有新版本并显示对话框，如果现在或之后实现。），我使用过：

Intent uppp = new Intent(this, AutoUpdate.class);
        startActivity(uppp,null);

代码完美无缺。但我不希望这创建第二个活动，重要的是在相同的 MainActivity 中显示对话框。

这是代码：

public class AutoUpdate extends AppCompatActivity {

    public static  String url1 = "localhost/version.json";
    String VersionUpdate;
    String Cambios;
    String link;
    String nombre;
    String ejecutar;

    private ProgressDialog pDialog;
    public static final int progress_bar_type = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_navigator);
        new VersionCheck().execute();
        permission_check();

    }

    public void permission_check() {
        if(ActivityCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED){

            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                requestPermissions(new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},100);

                return;
            }
        }

        //initialize();
    }

    public class VersionCheck extends AsyncTask<Void, Void, Void> {

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
        }
        @Override
        protected Void doInBackground(Void... arg0) {
            HttpHandler sh = new HttpHandler();
            String jsonStr = sh.makeServiceCall(url1);
            if (jsonStr != null){
                try {

                    JSONObject jsonObj = new JSONObject(jsonStr);
                    JSONArray obtener = jsonObj.getJSONArray("Obtener");
                    for (int i = 0; i < obtener.length(); i++)
                    {
                        JSONObject v = obtener.getJSONObject(i);
                        link = v.getString("link");
                        VersionUpdate = v.getString("version");
                        nombre = v.getString("nombre");
                        Cambios = "";
                        JSONArray cambiosArr = v.getJSONArray("cambios");
                        for (int j = 0; j < cambiosArr.length(); j++) {
                            Cambios += cambiosArr.getString(j) + "\n";
                        }
                    }
                }catch (final JSONException e) {

                    // Log.e(TAG, "Json parsing error: " + e.getMessage());
                    runOnUiThread(new Runnable() {
                        @Override
                        public void run() {

                            Toast.makeText(getApplicationContext(),
                                    "El formato de JSON es invalido: " + e.getMessage(),
                                    Toast.LENGTH_LONG)
                                    .show();
                        }
                    });

                }
            } else {

                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        Toast.makeText(getApplicationContext(),
                                "El servidor de comprobar la version esta caido, por favor chequear la version en: Ajustes > Comprobar",
                                Toast.LENGTH_LONG)
                                .show();
                    }
                });

            }
            return null;
        }

        @Override
        protected void onPostExecute (Void result){

            if (VersionUpdate != null) {

                super.onPostExecute(result);
                String VersionName = BuildConfig.VERSION_NAME;
                if (VersionUpdate.equals(VersionName)) {
                    /*Toast.makeText(getApplicationContext(),
                            "Version actual: " + VersionName,
                            Toast.LENGTH_LONG)
                            .show();*/
                    finish();
                } else {

                    AlertDialog.Builder builder = new AlertDialog.Builder(AutoUpdate.this);
                    builder.setTitle("Actualización");
                    builder.setIcon(R.mipmap.ic_launcher);
                    builder.setCancelable(false);
                    builder.setMessage("Actual: "+ VersionName + "\n"+ "Disponible: " + VersionUpdate  + "\n" + "\n" + "Incluye: " +"\n" +"\n" + Cambios + "\n")

                            .setPositiveButton("¡Actualizame!", new DialogInterface.OnClickListener() {
                                @Override
                                public void onClick(DialogInterface dialog, int which) {
                                    //Ejecutamos el class para descargar la version
                                    new DownloadFileFromURL().execute(link);

                                }
                            }
                            )
                            .setNegativeButton("Despues", new DialogInterface.OnClickListener() {
                                @Override
                                public void onClick(DialogInterface dialogInterface, int i) {
                                    finish();
                                }
                            });
                    AlertDialog alert = builder.create();
                    alert.show();


                }
            }
        }
    }

    @Override
    protected Dialog onCreateDialog(int id){
        switch (id){
            case progress_bar_type:
                pDialog = new ProgressDialog(this);
                pDialog.setMessage("Descargando actualización"+"\n"+"Espere...");
                pDialog.setIndeterminate(false);
                pDialog.setMax(100);
                pDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
                pDialog.setCancelable(false);
                pDialog.show();
                return pDialog;
            default:
                return null;
        }
    }

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

        @Override
        protected void onPreExecute(){
            super.onPreExecute();
            showDialog(progress_bar_type);
        }

        @Override
        protected  String doInBackground(String... f_url){
            int count;
            try{
                URL url = new URL(f_url[0]);
                URLConnection connection = url.openConnection();
                connection.connect();

                int lenghtOfFile = connection.getContentLength();

                InputStream input = new BufferedInputStream(url.openStream(), 8192);

                String storageDir = Environment.getExternalStorageDirectory().getAbsolutePath();
                String fileName = "/download/"+nombre+VersionUpdate+".apk";
                File arch = new File(storageDir+fileName);
                OutputStream output = new FileOutputStream(arch);
                ejecutar = storageDir+fileName;
                byte data[] = new byte[1024];
                long total = 0;

                while((count = input.read(data)) != -1){
                    total += count;

                    publishProgress(""+(int)((total*100)/lenghtOfFile));

                    output.write(data, 0, count);
                }
                output.flush();

                output.close();
                input.close();
            }catch (Exception e){
                //Log.e("Error: ", e.getMessage());
            }return null;

        }

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

        }

        @Override
        protected void onPostExecute(String file_url){

            dismissDialog(progress_bar_type);
            //aca ejecutamos al finalizar la descarga
            Intent intent = new Intent(Intent.ACTION_VIEW);
            intent.setDataAndType(Uri.fromFile(new File(ejecutar)),
                    "application/vnd.android.package-archive");
            intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); // without this flag android returned a intent error!
            startActivity(intent);
            finish(); //finalizamos cerrando la app
        }
    }

}

我将阅读它们，看看有什么可能的解决方案。

对于那些可能没有理解我的人，或者我没有给自己解释好。

编辑：

这是MainActivity：

当我打电话给＆＃34; AutoUpdate＆＃34; 时会发生这种情况：

如您所见，当我只想要对话框时，会创建另一个活动显示在MainActivity（图片1）

中

Answer 1

从gulp.src('src/assets/scss/**/*.scss')使用MainActivity方法<{1}}致电AutoUpdate.java

startActivityForResult()

机制的文档

Intent i = new Intent(this, AutoUpdate.class);
startActivityForResult(i, 1);

在完成后启动您想要结果的活动。退出此活动后，系统会使用给定的void startActivityForResult (Intent intent, int requestCode, Bundle options)调用onActivityResult() method。使用否定requestCode与调用requestCode

相同

有关更多示例，请同时查看此answer

在Android工作室中调用外部类

1 个答案: