如何在将数据导入数据库时​​使用进度条？

Question

就我而言，我需要将大量数据从文本文件导入数据库。在导入数据时，我想显示一些进度条以便让用户知道。我想知道如何在我的案例中实现进度条。现在我可以导入数据并获取总行数。这是当前代码

private fun importDialog(type: Int,context: Context) {
        val builder=AlertDialog.Builder(this)
        val inflater=this.layoutInflater
        val view=inflater.inflate(R.layout.import__dialog, null)
        builder.setView(view)
        val dialog: AlertDialog=builder.create()
        dialog.window?.attributes?.windowAnimations=type
        dialog.setMessage(context.getString(R.string.open_master))
        lbl=EditText(this)
        lbl=view.findViewById(R.id.edit_master)
        lbl.text=noti.toString()
        dialog.show()

        db=DataBaseHelper(this)

        btnimport=view.findViewById(R.id.img_import)

        btnimport.setOnClickListener {
            val fileintent=Intent(Intent.ACTION_GET_CONTENT)
            fileintent.type="txt/csv"
            try {
                startActivityForResult(fileintent, requestcode)
                dialog.show()
            } catch (e: ActivityNotFoundException) {
                lbl.text="No activity can handle picking a file. Showing alternatives."
            }
        }

        scan=view.findViewById<Button>(R.id.btn_scan)
        scan.setOnClickListener {

            import(this)

        }


    }

@SuppressLint("MissingSuperCall")
    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        if (data == null)
            return
        if (requestCode==requestcode) {
            val filepath=data.data
            file = filepath.toString()
            val cursor=contentResolver.openInputStream(android.net.Uri.parse(filepath.toString()))
            lbl.text=filepath.toString()
            master_path=filepath.toString()
            noti=cursor.toString()
            val db=this.openOrCreateDatabase("database.db", Context.MODE_PRIVATE, null)
            val tableName="Master"
            db.execSQL("delete from $tableName")
            val text =  StringBuilder()
            try {
                println("gg")
                if (resultCode == Activity.RESULT_OK) {
                    try {
                        val file=InputStreamReader(cursor)
                        var lineCount = 0
                        val buffer=BufferedReader(file)
                        buffer.readLine()
                        val contentValues=ContentValues()
                        db.beginTransaction()

                        while(true) {
                            val line=buffer.readLine()

                            if (line == null) break
                            lineCount++

                        }
                        println(lineCount.toString())
                        line = lineCount.toString().toInt()
                        db.setTransactionSuccessful()
                        db.endTransaction()
                    } catch (e: IOException) {
                        if (db.inTransaction())
                            db.endTransaction()
                        val d=Dialog(this)
                        d.setTitle(e.message.toString() + "first")
                        d.show()
                    }

                } else {
                    if (db.inTransaction())
                        db.endTransaction()
                    val d=Dialog(this)
                    d.setTitle("Only CSV files allowed")
                    d.show()
                }
            } catch (ex: Exception) {
                if (db.inTransaction())
                    db.endTransaction()

                val d=Dialog(this)
                d.setTitle(ex.message.toString() + "second")
                d.show()
            }

        }

    }

    fun import(context: Context) {

        val filepath=file
        val cursor=contentResolver.openInputStream(android.net.Uri.parse(filepath.toString()))
        lbl.text=filepath.toString()
        master_path=filepath.toString()
        noti=cursor.toString()
        val db=this.openOrCreateDatabase("database.db", Context.MODE_PRIVATE, null)
        val tableName="Master"
        db.execSQL("delete from $tableName")
        val text =  StringBuilder()
        try {
            println("gg")
                try {
                    val file=InputStreamReader(cursor)
                    var lineCount = 0
                    val buffer=BufferedReader(file)
                    buffer.readLine()
                    val contentValues=ContentValues()
                    db.beginTransaction()

                    while(true) {

                        lineCount++
                        in_line = lineCount

                        val line=buffer.readLine()
                        if (line == null) break

                        val article_array = ArrayList<String>()
                        var desc_array = ArrayList<String>()
                        var price_array = ArrayList<String>()
                        var isbn_array = ArrayList<String>()
                        var total_array = ArrayList<String>()

                        for(i in 0..12){
                            val article = line[i].toString().replace(" ","")
                            article_array.add(article)
                        }

                        for(i in 13..62){
                            val desc = line[i].toString()
                            desc_array.add(desc)
                        }
                        for(i  in 63..70){
                            val price = line[i].toString().replace(" ","")
                            price_array.add(price)
                        }
                        for(i in 71..line.length-1){
                            val isbn = line[i].toString().replace(" ","")
                            isbn_array.add(isbn)
                        }

                        val article_list = article_array.toString().replace(", ","").replace("[","").replace("]","")
                        val desc_list = desc_array.toString().replace(", ","").replace("[","").replace("]","")
                        val price_list = price_array.toString().replace(", ","").replace("[","").replace("]","")
                        val isbn_list:String = isbn_array.toString().replace(", ","").replace("[","").replace("]","")

                        total_array.add(article_list)
                        total_array.add(desc_list)
                        total_array.add(price_list)
                        total_array.add(isbn_list)


                        val article=total_array[0].toString()
                        val desc=total_array[1].toString()
                        val price=total_array[2].toString()
                        val isbn=total_array[3].toString()

                        contentValues.put("article", article)
                        contentValues.put("description", desc)
                        contentValues.put("price", price)
                        contentValues.put("isbn", isbn)
                        db.insert(tableName, null, contentValues)

                    }


                    db.setTransactionSuccessful()
                    db.endTransaction()
                } catch (e: IOException) {
                    if (db.inTransaction())
                        db.endTransaction()
                    val d=Dialog(this)
                    d.setTitle(e.message.toString() + "first")
                    d.show()
                }

        } catch (ex: Exception) {
            if (db.inTransaction())
                db.endTransaction()

            val d=Dialog(this)
            d.setTitle(ex.message.toString() + "second")
            d.show()
        }

    }

Answer 1

请尝试

private ProgressBar progressBar;

private fun importDialog(type: Int,context: Context) {

//
..
//
lbl=view.findViewById(R.id.edit_master)
progressBar = view.findViewById(R.id.progress_bar)
btnimport.setOnClickListener {
   progressBar.setVisibility(View.VISIBLE);
}
}

@SuppressLint("MissingSuperCall")
    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
  progressBar.setVisibility(View.GONE);
}

你只需hide/show进度条。