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創建一個應用程序-Java-從.txt文件創建一個arraylist,並為arraylist的特定行

[英]Creating an app - Java - create an arraylist from a .txt file and toast specific line of arraylist

我想做的是創建一個包含1000個左右條目的字符串數組。 而不是做:

public void DefaultGeneric(View v) throws FileNotFoundException{
    Random rand = new Random();
    int i = rand.nextInt(4) + 0;
    int j = rand.nextInt(4) + 0;
    String[] SomeThingA = {"yep","okay","nope"};    //I need this array to be much much larger but want a better way of doing it.
    String[] SomeThingB = {"test","test1","test2"}; //I need this array to be much much larger but want a better way of doing it.

    Toast.makeText(getBaseContext(), SomeThingA[i]+SomeThingB[j], Toast.LENGTH_LONG ).show();

}

聲明我的長數組,我一直在研究如何使用所有數組值創建一個.txt文件,然后使用arraylist。 但是每次嘗試都會失敗。 另外,一旦弄清楚如何使用arraylist,我就需要使用: Toast.makeText(getBaseContext(), variable, Toast.LENGTH_SHORT).show調用我的arraylist的特定行。

任何幫助將不勝感激。 謝謝!

我建議您如下創建JSON文件

[
  "entryOne",
  "entryTwo",
  "...",
  "entryN"
]

現在將此文件存儲在資產中,並按如下所示加載它(感謝https://stackoverflow.com/a/13814551/7274758

public String loadJSONFromAsset() {
    String json = null;
    try {
        InputStream is = getAssets().open("file_name.json");
        int size = is.available();
        byte[] buffer = new byte[size];
        is.read(buffer);
        is.close();
        json = new String(buffer, "UTF-8");
    }
    catch (IOException ex) {
        ex.printStackTrace();
        return null;
    }
    return json;
}

然后,您可以嘗試通過JSONArray創建此JSON字符串的數組

JSONArray arr = new JSONArray(loadJSONFromAsset());

要從行中檢索字符串,只需調用getString - arr.getString (rowNo)

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