How to set formatted JSON response string in a TextView?

The method @suhas_sm suggested is great, but fails to indent correctly if there's a key or a value that contains one of the special characters, "{" for example.

My solution (based on suhas_sm's method):

public static String formatString(String text){

    StringBuilder json = new StringBuilder();
    String indentString = "";

    boolean inQuotes = false;
    boolean isEscaped = false;

    for (int i = 0; i < text.length(); i++) {
        char letter = text.charAt(i);

        switch (letter) {
            case '\\':
                isEscaped = !isEscaped;
                break;
            case '"':
                if (!isEscaped) {
                    inQuotes = !inQuotes;
                }
                break;
            default:
                isEscaped = false;
                break;
        }

        if (!inQuotes && !isEscaped) {
            switch (letter) {
                case '{':
                case '[':
                    json.append("\n" + indentString + letter + "\n");
                    indentString = indentString + "\t";
                    json.append(indentString);
                    break;
                case '}':
                case ']':
                    indentString = indentString.replaceFirst("\t", "");
                    json.append("\n" + indentString + letter);
                    break;
                case ',':
                    json.append(letter + "\n" + indentString);
                    break;
                default:
                    json.append(letter);
                    break;
            }
        } else {
            json.append(letter);
        }
    }

    return json.toString();
}

I wrote the following utility method to format and indent (no colors yet):

public static String formatString(String text){

    StringBuilder json = new StringBuilder();
    String indentString = "";

    for (int i = 0; i < text.length(); i++) {
        char letter = text.charAt(i);
        switch (letter) {
            case '{':
            case '[':
                json.append("\n" + indentString + letter + "\n");
                indentString = indentString + "\t";
                json.append(indentString);
                break;
            case '}':
            case ']':
                indentString = indentString.replaceFirst("\t", "");
                json.append("\n" + indentString + letter);
                break;
            case ',':
                json.append(letter + "\n" + indentString);
                break;

            default:
                json.append(letter);
                break;
        }
    }

    return json.toString();
}

Do you want to parse it or simply show the raw JSON response? If the former:

How to parse JSON in Android

If you want it to be formatted, you can do it manually:

example:

{"J":5,"0":"N"}

---

first remove "{,}", split this array '"J":5,"0":"N"' by ',' and then for the colouring just check if a value has quotations marks or not and choose accordingly. Just a simple string manipulation.

Then output:

• {
• foreach loop of the array items with colouring
• }

Much simpler approch, there is a toString method with indent space param for JSONObject,

can be used like this :

JSONObject jsonObject = new JSONObject(jsonString);
textView.setText(jsonObject.toString(4));// 4 is number of spaces for indent

same is applicable for JSONArray

reference :

https://developer.android.com/reference/org/json/JSONObject#toString(int)

https://alvinalexander.com/android/android-json-print-json-string-human-readable-format-debugging