android.text.TextPaint#getTextBounds ( )源码实例Demo

@Override
public void updateDrawState(TextPaint ds) {
    super.updateDrawState(ds);

    if (mGravity == SpecialGravity.BOTTOM) return;

    mTextView.getPaint().getTextBounds(mNormalSizeText, 0, mNormalSizeText.length(), mTextViewRect);
    ds.getTextBounds(mText, 0, mText.length(), mTextRect);
    int mMainTextHeight = mTextViewRect.height();

    int offset = mTextViewRect.bottom - mTextRect.bottom;
    switch (mGravity) {
        case SpecialGravity.TOP:
            mOffsetBaselineShift = mMainTextHeight - mTextRect.height() - offset;
            break;
        case SpecialGravity.CENTER:
            mOffsetBaselineShift = mMainTextHeight / 2 - mTextRect.height() / 2 - offset;
            break;
    }

    ds.baselineShift -= mOffsetBaselineShift;
}
 

MaskMorphDrawable(Context context, TextPaint textPaint,
                  int baseline, float charWidth, int insetStart) {
    this.insetStart = insetStart;
    this.baseline = baseline;
    this.charWidth = charWidth;
    paint = new TextPaint(textPaint);
    Rect maskBounds = new Rect();
    paint.getTextBounds(PASSWORD_MASK, 0, 1, maskBounds);
    maskDiameter = maskBounds.height();
    maskCenterY = (maskBounds.top + maskBounds.bottom) / 2f;
    showPasswordDuration =
            context.getResources().getInteger(R.integer.show_password_duration);
    hidePasswordDuration =
            context.getResources().getInteger(R.integer.hide_password_duration);
    fastOutSlowIn = AnimUtils.getFastOutSlowInInterpolator(context);
}
 

private void drawMinutesValues(Canvas canvas) {

        if (!showMinutesValues)
            return;

        Rect rect = new Rect();

        Typeface typeface = ResourcesCompat.getFont(getContext(), R.font.proxima_nova_thin);
        TextPaint textPaint = new TextPaint();
        textPaint.setColor(minutesProgressColor);
        textPaint.setTypeface(typeface);
        textPaint.setTextSize(size * MINUTES_TEXT_SIZE);

        int rText = (int) (centerX - ((1 - minutesValuesFactor - (2 * DEFAULT_BORDER_THICKNESS) - MINUTES_TEXT_SIZE) * radius));

        for (int i = 0; i < FULL_ANGLE; i = i + QUARTER_DEGREE_STEPS) {

            int value = i / 6;
            String formatted;
            switch (valueType) {

                case arabic:
                    formatted = ClockUtils.toArabic(value);
                    break;

                case roman:
                    formatted = ClockUtils.toRoman(value);
                    break;

                default:
                    formatted = String.format(Locale.getDefault(), "%02d", value);
                    break;
            }

            int textX = (int) (centerX + rText * Math.cos(Math.toRadians(REGULAR_ANGLE - i)));
            int textY = (int) (centerX - rText * Math.sin(Math.toRadians(REGULAR_ANGLE - i)));
            textPaint.getTextBounds(formatted, 0, formatted.length(), rect);
            canvas.drawText(formatted, textX - rect.width() / formatted.length(), textY + rect.height() / formatted.length(), textPaint);
        }
    }
 

public static WritableArray getFontMetrics(CharSequence text, Layout layout, TextPaint paint, Context context) {
  DisplayMetrics dm = context.getResources().getDisplayMetrics();
  WritableArray lines = Arguments.createArray();
  // To calculate xHeight and capHeight we have to render an "x" and "T" and manually measure their height.
  // In order to get more precision than Android offers, we blow up the text size by 100 and measure it.
  // Luckily, text size affects rendering linearly, so we can do this trick.
  TextPaint paintCopy = new TextPaint(paint);
  paintCopy.setTextSize(paintCopy.getTextSize() * AMPLIFICATION_FACTOR);
  Rect capHeightBounds = new Rect();
  paintCopy.getTextBounds(CAP_HEIGHT_MEASUREMENT_TEXT, 0, CAP_HEIGHT_MEASUREMENT_TEXT.length(), capHeightBounds);
  double capHeight = capHeightBounds.height() / AMPLIFICATION_FACTOR / dm.density;
  Rect xHeightBounds = new Rect();
  paintCopy.getTextBounds(X_HEIGHT_MEASUREMENT_TEXT, 0, X_HEIGHT_MEASUREMENT_TEXT.length(), xHeightBounds);
  double xHeight = xHeightBounds.height() / AMPLIFICATION_FACTOR / dm.density;
  for (int i = 0; i < layout.getLineCount(); i++) {
    Rect bounds = new Rect();
    layout.getLineBounds(i, bounds);
    WritableMap line = Arguments.createMap();
    line.putDouble("x", layout.getLineLeft(i) / dm.density);
    line.putDouble("y", bounds.top / dm.density);
    line.putDouble("width", layout.getLineWidth(i) / dm.density);
    line.putDouble("height", bounds.height() / dm.density);
    line.putDouble("descender", layout.getLineDescent(i) / dm.density);
    line.putDouble("ascender", -layout.getLineAscent(i) / dm.density);
    line.putDouble("baseline", layout.getLineBaseline(i) / dm.density);
    line.putDouble("capHeight", capHeight);
    line.putDouble("xHeight", xHeight);
    line.putString(
        "text", text.subSequence(layout.getLineStart(i), layout.getLineEnd(i)).toString());
    lines.pushMap(line);
  }
  return lines;
}
 

PasswordCharacter(String password, int index, TextPaint paint,
                  float maskCharDiameter, float maskCenterY) {
    paint.getTextBounds(password, index, index + 1, bounds);
    // scale the mask from the character width, down to it's own width
    maskToTextScale = Math.max(1f, bounds.width() / maskCharDiameter);
    // scale text from it's height down to the mask character height
    textToMaskScale = Math.min(0f, 1f / (bounds.height() / maskCharDiameter));
    // difference between mask & character center
    textOffsetY = maskCenterY - bounds.exactCenterY();
}
 

public static float getFontCapHeight (Typeface font, float fontSize)
{
    TextPaint textPaint = new TextPaint(Paint.ANTI_ALIAS_FLAG);
    textPaint.setTypeface(font);
    textPaint.setTextSize(fontSize);
    Rect tempRect = new Rect();
    textPaint.getTextBounds("H", 0, 1, tempRect);
    return tempRect.height();
}
 

GifBadge(Context context) {
    if (bitmap == null) {
        final DisplayMetrics dm = context.getResources().getDisplayMetrics();
        final float density = dm.density;
        final float scaledDensity = dm.scaledDensity;
        final TextPaint textPaint = new TextPaint(Paint.ANTI_ALIAS_FLAG | Paint
                .SUBPIXEL_TEXT_FLAG);
        textPaint.setTypeface(Typeface.create(TYPEFACE, TYPEFACE_STYLE));
        textPaint.setTextSize(TEXT_SIZE * scaledDensity);

        final float padding = PADDING * density;
        final float cornerRadius = CORNER_RADIUS * density;
        final Rect textBounds = new Rect();
        textPaint.getTextBounds(GIF, 0, GIF.length(), textBounds);
        height = (int) (padding + textBounds.height() + padding);
        width = (int) (padding + textBounds.width() + padding);
        bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
        bitmap.setHasAlpha(true);
        final Canvas canvas = new Canvas(bitmap);
        final Paint backgroundPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
        backgroundPaint.setColor(BACKGROUND_COLOR);
        canvas.drawRoundRect(0, 0, width, height, cornerRadius, cornerRadius,
                backgroundPaint);
        // punch out the word 'GIF', leaving transparency
        textPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
        canvas.drawText(GIF, padding, height - padding, textPaint);
    }
    paint = new Paint();
}
 

GifBadge(Context context) {
    if (bitmap == null) {
        final DisplayMetrics dm = context.getResources().getDisplayMetrics();
        final float density = dm.density;
        final float scaledDensity = dm.scaledDensity;
        final TextPaint textPaint = new TextPaint(Paint.ANTI_ALIAS_FLAG | Paint
                .SUBPIXEL_TEXT_FLAG);
        textPaint.setTypeface(Typeface.create(TYPEFACE, TYPEFACE_STYLE));
        textPaint.setTextSize(TEXT_SIZE * scaledDensity);

        final float padding = PADDING * density;
        final float cornerRadius = CORNER_RADIUS * density;
        final Rect textBounds = new Rect();
        textPaint.getTextBounds(GIF, 0, GIF.length(), textBounds);
        height = (int) (padding + textBounds.height() + padding);
        width = (int) (padding + textBounds.width() + padding);
        bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
        bitmap.setHasAlpha(true);
        final Canvas canvas = new Canvas(bitmap);
        final Paint backgroundPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
        backgroundPaint.setColor(BACKGROUND_COLOR);
        canvas.drawRoundRect(0, 0, width, height, cornerRadius, cornerRadius,
                backgroundPaint);
        // punch out the word 'GIF', leaving transparency
        textPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
        canvas.drawText(GIF, padding, height - padding, textPaint);
    }
    paint = new Paint();
}
 

private static float getTextYOffset(final String text,final TextPaint paint,final int height)
{
final Rect bounds=new Rect();
paint.getTextBounds(text,0,text.length(),bounds);
final int textHeight=bounds.bottom-bounds.top;
return height-(height-textHeight)/2-(int)paint.descent();
}
 

/**
 * Given a height, returns a Y offset that will draw the text in the middle of the height.
 */
protected float getTextYOffset(String text, TextPaint paint, int height) {
    Rect bounds = new Rect();
    paint.getTextBounds(text, 0, text.length(), bounds);
    int textHeight = bounds.bottom - bounds.top;
    return height - ((height - textHeight) / 2) - (int) paint.descent() / 2;
}
 

public static Bitmap getAlphabetImage(Context context, String content) {
    Resources res = context.getResources();
    Bitmap mDefaultBitmap = BitmapFactory.decodeResource(res, android.R.drawable.sym_def_app_icon);
    int width = mDefaultBitmap.getWidth();
    int height = mDefaultBitmap.getHeight();
    TextPaint mPaint = new TextPaint();
    mPaint.setTypeface(OControlHelper.boldFont());
    mPaint.setColor(Color.WHITE);
    mPaint.setTextAlign(Paint.Align.CENTER);
    mPaint.setAntiAlias(true);
    int textSize = res.getDimensionPixelSize(R.dimen.text_size_xxlarge);

    Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas();
    Rect mBounds = new Rect();
    canvas.setBitmap(bitmap);
    canvas.drawColor(OStringColorUtil.getStringColor(context, content));
    if (content == null || content.trim().length() == 0) {
        content = "?";
    }
    char[] alphabet = {Character.toUpperCase(content.trim().charAt(0))};
    mPaint.setTextSize(textSize);
    mPaint.getTextBounds(alphabet, 0, 1, mBounds);
    canvas.drawText(alphabet, 0, 1, 0 + width / 2,
            0 + height / 2 + (mBounds.bottom - mBounds.top) / 2, mPaint);
    return bitmap;
}
 

/**
 * 计算TextView中字符串的长度
 *
 * @param text 要计算的字符串
 * @param Size 字体大小
 * @return TextView中字符串的长度
 */
public float getTextWidth(BarrageItem item, String text, float Size) {
    Rect bounds = new Rect();
    TextPaint paint;
    paint = item.textView.getPaint();
    paint.getTextBounds(text, 0, text.length(), bounds);
    return bounds.width();
}
 

public static int getTextWidth(String str, TextView tvText) {
    Rect bounds = new Rect();
    TextPaint paint = tvText.getPaint();
    paint.getTextBounds(str, 0, str.length(), bounds);
    return bounds.width();
}
 

private void drawHoursValues(Canvas canvas) {

        if (!showHoursValues)
            return;

        Rect rect = new Rect();

        TextPaint textPaint = new TextPaint();
        textPaint.setFlags(Paint.ANTI_ALIAS_FLAG);
        textPaint.setAntiAlias(true);
        textPaint.setColor(this.valuesColor);
        textPaint.setTypeface(this.valuesFont);
        textPaint.setTextSize(size * DEFAULT_HOURS_VALUES_TEXT_SIZE);

        float degreeSpace = 0f;
        if (showDegrees)
            degreeSpace = DEFAULT_DEGREE_STROKE_WIDTH + 0.06f;

        int rText = (int) (centerX - (size * DEFAULT_HOURS_VALUES_TEXT_SIZE) - (size * degreeSpace));

        for (int i = FULL_ANGLE; i > 0; i = i - valueStep.getId()) {

            int value = i / 30;
            String formatted;
            switch (valueType) {

                case roman:
                    formatted = ClockUtils.toRoman(value);
                    break;

                case arabic:
                    formatted = ClockUtils.toArabic(value);
                    break;

                default:
                    formatted = String.format(Locale.getDefault(), "%02d", value);
                    break;
            }

            if (valueDisposition.getId() == 0) {
                if ((i % REGULAR_ANGLE) == 0) {
                    textPaint.setTextSize(size * DEFAULT_HOURS_VALUES_TEXT_SIZE);
                    textPaint.setAlpha(FULL_ALPHA);
                } else {
                    textPaint.setTextSize(size * (DEFAULT_HOURS_VALUES_TEXT_SIZE - 0.03f));
                    textPaint.setAlpha(CUSTOM_ALPHA);
                }
            } else {
                textPaint.setTextSize(size * DEFAULT_HOURS_VALUES_TEXT_SIZE);
                textPaint.setAlpha(FULL_ALPHA);
            }


            int textX = (int) (centerX + rText * Math.cos(Math.toRadians(REGULAR_ANGLE - i)));
            int textY = (int) (centerX - rText * Math.sin(Math.toRadians(REGULAR_ANGLE - i)));
            textPaint.getTextBounds(formatted, 0, formatted.length(), rect);
            canvas.drawText(formatted, textX - rect.width() / formatted.length(), textY + rect.height() / formatted.length(), textPaint);
        }

    }
 

private void init(Context context, AttributeSet attrs) {
    TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.WaveTextView);
    mText = typedArray.getString(R.styleable.WaveTextView_text);
    mTextSize = typedArray.getDimension(R.styleable.WaveTextView_size, 26);
    mTextColor = typedArray.getColor(R.styleable.WaveTextView_color, Color.BLACK);
    A = typedArray.getInteger(R.styleable.WaveTextView_amplitude, 100);
    isBold = typedArray.getInteger(R.styleable.WaveTextView_style, 0);
    typedArray.recycle();

    mTextPaint = new TextPaint();
    mTextPaint.setAntiAlias(true);
    mTextPaint.setTextSize(mTextSize);
    mTextPaint.setColor(mTextColor);
    if(isBold == 1) mTextPaint.setFakeBoldText(true);
    //mTextPaint.setTypeface(Typeface.defaultFromStyle(Typeface.BOLD));
    mTextPath = new Path();
    mTextWidth = (int) mTextPaint.measureText(mText);
    Paint.FontMetricsInt fontMetrics = mTextPaint.getFontMetricsInt();
    mTextHeight = fontMetrics.bottom - fontMetrics.top;
    Rect rect = new Rect();
    mTextPaint.getTextBounds(mText, 0, mText.length(), rect);
    mTextCenter = rect.height() / 2;

    //φ的取值范围为正弦函数的一个周期：2π
    mValueAnimator = ValueAnimator.ofFloat(0, (float) (2 * Math.PI));
    mValueAnimator.setInterpolator(new LinearInterpolator());
    mValueAnimator.addUpdateListener(animation -> {
        float progress = (float) animation.getAnimatedValue();
        φ = progress;
        a = (float) (1 - progress / (2 * Math.PI)) * A;
        LogUtil.d(TAG, "addUpdateListener(), a = " + a + ", φ = " + φ);
        postInvalidate();
    });
    mValueAnimator.setDuration(2500);
    postDelayed(() -> mValueAnimator.start(), 100);

    for(int i = 0; i <= SAMPLING_SIZE; i++) {
        float gap = (float) mTextWidth / SAMPLING_SIZE;
        mSamplingX[i] = i * gap;
        mMapX[i] = mSamplingX[i] / (float) mTextWidth * 4 - 2;
    }
}
 

/**
 * build a bitmap from a text.
 *
 * @return {@link Bitmap} the bitmap return.
 */
public static Bitmap textAsBitmap(Context context, WatermarkText watermarkText) {
    TextPaint watermarkPaint = new TextPaint();
    watermarkPaint.setColor(watermarkText.getTextColor());
    watermarkPaint.setStyle(watermarkText.getTextStyle());

    if (watermarkText.getTextAlpha() >= 0 && watermarkText.getTextAlpha() <= 255) {
        watermarkPaint.setAlpha(watermarkText.getTextAlpha());
    }

    float value = (float) watermarkText.getTextSize();
    int pixel = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
            value, context.getResources().getDisplayMetrics());
    watermarkPaint.setTextSize(pixel);

    if (watermarkText.getTextShadowBlurRadius() != 0
            || watermarkText.getTextShadowXOffset() != 0
            || watermarkText.getTextShadowYOffset() != 0) {
        watermarkPaint.setShadowLayer(watermarkText.getTextShadowBlurRadius(),
                watermarkText.getTextShadowXOffset(),
                watermarkText.getTextShadowYOffset(),
                watermarkText.getTextShadowColor());
    }

    if (watermarkText.getTextFont() != 0) {
        Typeface typeface = ResourcesCompat.getFont(context, watermarkText.getTextFont());
        watermarkPaint.setTypeface(typeface);
    }

    watermarkPaint.setAntiAlias(true);
    watermarkPaint.setTextAlign(Paint.Align.LEFT);
    watermarkPaint.setStrokeWidth(5);

    float baseline = (int) (-watermarkPaint.ascent() + 1f);
    Rect bounds = new Rect();
    watermarkPaint.getTextBounds(watermarkText.getText(),
            0, watermarkText.getText().length(), bounds);

    int boundWidth = bounds.width() + 20;
    int mTextMaxWidth = (int) watermarkPaint.measureText(watermarkText.getText());
    if (boundWidth > mTextMaxWidth) {
        boundWidth = mTextMaxWidth;
    }
    StaticLayout staticLayout = new StaticLayout(watermarkText.getText(),
            0, watermarkText.getText().length(),
            watermarkPaint, mTextMaxWidth, android.text.Layout.Alignment.ALIGN_NORMAL, 2.0f,
            2.0f, false);

    int lineCount = staticLayout.getLineCount();
    int height = (int) (baseline + watermarkPaint.descent() + 3) * lineCount;
    Bitmap image = Bitmap.createBitmap(1, 1, Bitmap.Config.ARGB_8888);
    if (boundWidth > 0 && height > 0) {
        image = Bitmap.createBitmap(boundWidth, height, Bitmap.Config.ARGB_8888);
    }
    Canvas canvas = new Canvas(image);
    canvas.drawColor(watermarkText.getBackgroundColor());
    staticLayout.draw(canvas);
    return image;
}
 

public Bitmap convertToBitmapFromText() {
    if (mTextSize == 0.0F) {
        throw new WaterMarkCreatorException("Did not provide the text size");
    }
    if (mTextColor == 0) {
        throw new WaterMarkCreatorException("Did not provide the text color");
    }

    TextPaint paint = new TextPaint();
    paint.setColor(mTextColor);
    paint.setTextSize(mTextSize);
    paint.setStrokeWidth(5);
    paint.setTypeface(Typeface.MONOSPACE);

    paint.setAntiAlias(true);
    paint.setTextAlign(Paint.Align.LEFT);

    //ascent : The recommended distance above the baseline for singled spaced text
    float baseline = (int) (-paint.ascent() + 3f); // ascent() is negative
    Log.e("test", " " + paint.ascent() + " baseline: " + baseline);

    // First decode with Rect to check dimensions
    Rect bounds = new Rect();
    paint.getTextBounds(mText.toString(), 0, mText.length(), bounds);

    int boundWidth = bounds.width() + MARGIN_RIGHT;
    // mRequestWidth must be in pixels
    if (boundWidth > mTextMaxWidth) {
        boundWidth = mTextMaxWidth;
    }
    StaticLayout staticLayout = new StaticLayout(mText, 0, mText.length(),
            paint, mTextMaxWidth, android.text.Layout.Alignment.ALIGN_NORMAL, 1.0f,
            1.0f, false);

    int lineCount = staticLayout.getLineCount();
    //Descent: The recommended distance below the baseline for singled spaced text
    int height = (int) (baseline + paint.descent() + 3) * lineCount + 10;

    Bitmap image = Bitmap.createBitmap(boundWidth, height, Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(image);
    canvas.drawARGB(0xFF, 0xFF, 0xFF, 0xFF);
    staticLayout.draw(canvas);
    return image;
}
 

/***
 * this method calculate height for a line of text according to defined TextPaint
 * @param textPaint
 */
private void setLineHeight(TextPaint textPaint) {

    Rect bounds=new Rect();
    String sampleStr="این حسین کیست که عالم همه دیوانه اوست";
    textPaint.getTextBounds(sampleStr, 0,sampleStr.length(), bounds);

    setLineHeight(bounds.height());

}
 

/***
 * this method calculate height for a line of text according to defined TextPaint
 * @param textPaint
 */
private void setLineHeight(TextPaint textPaint) {

    Rect bounds=new Rect();
    String sampleStr="این حسین کیست که عالم همه دیوانه اوست";
    textPaint.getTextBounds(sampleStr, 0,sampleStr.length(), bounds);

    setLineHeight(bounds.height());

}
 

/**
 * 计算文字实际占用区域
 *
 * @param measurePaint 计算用文字的画笔
 * @param rect 计算后的矩形（此矩形位文字的实际占用区域）
 */
public static void measureTextArea(TextPaint measurePaint, Rect rect) {
  String test = "9.Y";
  measurePaint.getTextBounds(test, 0, test.length(), rect);
}