hackware1993/MagicIndicator · error · IllegalArgumentException

mode " + mode + " not supported.

Error message

mode " + mode + " not supported.

What it means

LinePagerIndicator.setMode() only accepts MODE_EXACTLY, MODE_MATCH_EDGE, or MODE_WRAP_CONTENT. Any other int (including values from another indicator's constants or a raw integer) throws IllegalArgumentException. It fails fast because an unsupported mode would produce undefined indicator sizing.

Solutions

  1. Use one of the three constants defined on LinePagerIndicator: MODE_EXACTLY, MODE_MATCH_EDGE, or MODE_WRAP_CONTENT
  2. Check that you are importing net.lucode.hackware.magicindicator.buildins.commonnavigator.indicators.LinePagerIndicator and referencing its constants, not another class's
  3. If the mode comes from stored config/attributes, validate it against the three allowed values before calling setMode

Example fix

// before
indicator.setMode(3);

// after
indicator.setMode(LinePagerIndicator.MODE_MATCH_EDGE);
Defensive patterns

Strategy: validation

Validate before calling

private static final int[] ALLOWED_MODES = {
    LinePagerIndicator.MODE_EXACTLY,
    LinePagerIndicator.MODE_MATCH_EDGE,
    LinePagerIndicator.MODE_WRAP_CONTENT
};

static boolean isValidMode(int mode) {
    for (int m : ALLOWED_MODES) {
        if (m == mode) return true;
    }
    return false;
}

// before calling:
if (isValidMode(mode)) indicator.setMode(mode);

Type guard

static boolean isLinePagerIndicatorMode(int mode) {
    return mode == LinePagerIndicator.MODE_EXACTLY
        || mode == LinePagerIndicator.MODE_MATCH_EDGE
        || mode == LinePagerIndicator.MODE_WRAP_CONTENT;
}

Try / catch

try {
    indicator.setMode(mode);
} catch (IllegalArgumentException e) {
    Log.w("MagicIndicator", "Unsupported mode " + mode + ", falling back", e);
    indicator.setMode(LinePagerIndicator.MODE_EXACTLY);
}

Prevention

When it happens

Trigger: Calling setMode() with an int that is not one of LinePagerIndicator.MODE_EXACTLY, MODE_MATCH_EDGE, or MODE_WRAP_CONTENT — e.g. passing LinePagerIndicator.MODE_FIXED (which does not exist), a ViewPager.LayoutParams constant, or a literal like 3.

Common situations: Copy-pasting mode constants from a different indicator class (e.g. CommonPagerTitleView or CirclePagerIndicator), mistyping a constant name and resolving to a wrong int, or persisting/restoring mode as an int from preferences where the stored value is out of range.

Understand the failure class

Background: Invalid enum value errors: "Unknown type", "Invalid scope", "must be one of" — when a string is not on the library's allowed list — this error's family across 23 libraries.

Related errors

AI-assisted analysis of hackware1993/MagicIndicator@fe22c7dc45 (2026-09-10). Data as JSON: /api/errors/676f73aaa1fdd561. Report an issue: GitHub.

Appendix: source

Thrown at magicindicator/src/main/java/net/lucode/hackware/magicindicator/buildins/commonnavigator/indicators/LinePagerIndicator.java:173

    }

    public float getRoundRadius() {
        return mRoundRadius;
    }

    public void setRoundRadius(float roundRadius) {
        mRoundRadius = roundRadius;
    }

    public int getMode() {
        return mMode;
    }

    public void setMode(int mode) {
        if (mode == MODE_EXACTLY || mode == MODE_MATCH_EDGE || mode == MODE_WRAP_CONTENT) {
            mMode = mode;
        } else {
            throw new IllegalArgumentException("mode " + mode + " not supported.");
        }
    }

    public Paint getPaint() {
        return mPaint;
    }

    public List<Integer> getColors() {
        return mColors;
    }

    public void setColors(Integer... colors) {
        mColors = Arrays.asList(colors);
    }

    public Interpolator getStartInterpolator() {
        return mStartInterpolator;
    }

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