AutofitTextView.java 文件源码

/**
 * Re size the font so the specified text fits in the text box assuming the text box is the
 * specified width.
 */
private void refitText() {
    if (!mSizeToFit) {
        return;
    }

    if (mMaxLines <= 0) {
        // Don't auto-size since there's no limit on lines.
        return;
    }

    CharSequence text = getText();
    TransformationMethod method = getTransformationMethod();
    if (method != null) {
        text = method.getTransformation(text, this);
    }
    int targetWidth = getWidth() - getPaddingLeft() - getPaddingRight();
    if (targetWidth > 0) {
        Context context = getContext();
        Resources r = Resources.getSystem();
        DisplayMetrics displayMetrics;

        float size = mMaxTextSize;
        float high = size;
        float low = 0;

        if (context != null) {
            r = context.getResources();
        }
        displayMetrics = r.getDisplayMetrics();

        mPaint.set(getPaint());
        mPaint.setTextSize(size);

        if ((mMaxLines == 1 && mPaint.measureText(text, 0, text.length()) > targetWidth)
                || getLineCount(text, mPaint, size, targetWidth, displayMetrics) > mMaxLines) {
            size = getTextSize(text, mPaint, targetWidth, mMaxLines, low, high, mPrecision,
                    displayMetrics);
        }

        if (size < mMinTextSize) {
            size = mMinTextSize;
        }

        super.setTextSize(TypedValue.COMPLEX_UNIT_PX, size);
    }
}