Java Code Examples for android.graphics.Canvas#drawText()

protected Bitmap doInBackground(Object task, int index, long position) {
    try {
        Thread.sleep(100);
    } catch (InterruptedException ex) {
        // Thread might be interrupted by cancel() call.
    }
    if (isCancelled(task)) {
        return null;
    }
    String path = String.format(mPathPattern, (index + 1));
    if (new File(path).exists()) {
        return BitmapFactory.decodeFile(path);
    } else {
        Bitmap bmp = Bitmap.createBitmap(160, 160, Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(bmp);
        canvas.drawColor(Color.YELLOW);
        canvas.drawText(path, 10, 80, mPaint);
        canvas.drawText(Integer.toString(index), 10, 150, mPaint);
        return bmp;
    }
}
 

/**
 * Create a bitmap from a text
 *
 * @param text
 *         Text which the bitmap is created for
 * @param textSize
 *         Text size
 * @param textColor
 *         Text color
 * @param typeface
 *         Typeface of text
 *
 * @return a bitmap on which is text is drawn
 */
public static Bitmap createBitmapFromText(String text, float textSize, int textColor,
                                          Typeface typeface) {
    Paint paint = new Paint(ANTI_ALIAS_FLAG);
    paint.setTextSize(textSize);
    paint.setColor(textColor);
    paint.setTypeface(typeface);
    paint.setTextAlign(Paint.Align.LEFT);
    float baseline = -paint.ascent();
    int width = (int) (paint.measureText(text) + 0.5f);
    int height = (int) (baseline + paint.descent() + 0.5f);

    Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(bitmap);
    canvas.drawText(text, 0, baseline, paint);
    return bitmap;
}
 

/**
 * Override this method
 */
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    // Get the focus change the background color.
    int height = getHeight();// Get the corresponding height
    int width = getWidth(); // Get the corresponding width

    float singleHeight = (height * 1f) / b.length;// Gets the height of each letter
    singleHeight = (height * 1f - singleHeight / 2) / b.length;
    for (int i = 0; i < b.length; i++) {
        paint.setColor(Color.rgb(86, 86, 86));
        paint.setTypeface(Typeface.DEFAULT);
        paint.setAntiAlias(true);
        paint.setTextSize(23);

        // x-coordinate of the middle - half the width of the string.
        float xPos = width / 2 - paint.measureText(b[i]) / 2;
        float yPos = singleHeight * i + singleHeight;
        canvas.drawText(b[i], xPos, yPos, paint);
        paint.reset();// Reset Brushes
    }
}
 

@Override
public void drawText(@NonNull Canvas canvas, @NonNull BaseKChartView view, int position, float x, float y) {
    y = y - BaseKChartView.mChildTextPaddingY;
    x = BaseKChartView.mChildTextPaddingX;

    String text = "";
    IRSI point = (IRSI) view.getItem(position);
    text = "RSI1:" + view.formatValue(point.getRsi1()) + " ";
    canvas.drawText(text, x, y, mRSI1Paint);
    x += mRSI1Paint.measureText(text);

    x += BaseKChartView.mTextPaddingLeft;
    text = "RSI2:" + view.formatValue(point.getRsi2()) + " ";
    canvas.drawText(text, x, y, mRSI2Paint);
    x += mRSI2Paint.measureText(text);

    x += BaseKChartView.mTextPaddingLeft;
    text = "RSI3:" + view.formatValue(point.getRsi3()) + " ";
    canvas.drawText(text, x, y, mRSI3Paint);
}
 

@Override
protected void onDraw(Canvas canvas) {

    mInnerRectF.set(0, 0, mViewSize, mViewSize);
    mInnerRectF.offset((getWidth() - mViewSize) / 2, (getHeight() - mViewSize) / 2);

    float centerX = mInnerRectF.centerX();
    float centerY = mInnerRectF.centerY();

    int xPos = (int) centerX;
    int yPos = (int) (centerY - (mTitleTextPaint.descent() + mTitleTextPaint.ascent()) / 2);

    canvas.drawOval(mInnerRectF, mBackgroundPaint);

    canvas.drawText(mTitleText,
            xPos,
            yPos,
            mTitleTextPaint);
}
 

public void draw(Canvas canvas, Paint paint) {
    if (curIndex < 1 || curIndex > word.length) {
        return;
    }
    for (int i = 0; i < curIndex; i++) {
        paint.setTextSize(texts[i].size);
        if (i == curIndex - 1) {
            paint.setTextAlign(Paint.Align.CENTER);
            // 绘制中间的字母
            canvas.drawText(texts[i].content, texts[i].x, mBaseLine, paint);
        } else {
            // 由于文字绘制的原点影响了文字的间距,因为文字的宽度都是通过align.right进行一个间距的计算的,所以
            // 当以中心为绘制原点的时候,相同的间距会变成原来的一半,这样就会导致间距缩小,尤其是小字体像i等,所以通过
            // 设置不同的绘制原点,加上不同的位移来解决这个问题.
            paint.setTextAlign(Paint.Align.LEFT);
                if (texts[i].direction == Text.DIRECTION_RIGHT) {
                    canvas.drawText(texts[i].content,
                            texts[i].x + paint.measureText(word[curIndex - 1]) / 2 + texts[i].extraX, mBaseLine, paint);
                } else if (texts[i].direction == Text.DIRECTION_LEFT) {
                    canvas.drawText(texts[i].content,
                            texts[i].x - paint.measureText(word[i]) - paint.measureText(word[curIndex - 1]) / 2 + texts[i].extraX, mBaseLine, paint);
                }
        }
    }
}
 

private void drawPathAContentBitmap(Bitmap bitmap, Paint pathPaint) {
    Canvas mCanvas = new Canvas(bitmap);
    //下面开始绘制区域内的内容...
    mCanvas.drawPath(getPathDefault(), pathPaint);
    mCanvas.drawText("这是在A区域的内容...AAAA", viewWidth - 260, viewHeight - 100, textPaint);

    //结束绘制区域内的内容...
}
 

@Override
protected void onDrawText(Canvas canvas, Calendar calendar, int x, boolean hasScheme, boolean isSelected) {
    float baselineY = mTextBaseLine - dipToPx(getContext(), 1);
    int cx = x + mItemWidth / 2;
    if (isSelected) {
        canvas.drawText(calendar.isCurrentDay() ? "今" : "选",
                cx,
                baselineY,
                mSelectTextPaint);
    } else if (hasScheme) {
        canvas.drawText(calendar.isCurrentDay() ? "今" : String.valueOf(calendar.getDay()),
                cx,
                baselineY,
                calendar.isCurrentDay() ? mCurDayTextPaint :
                        calendar.isCurrentMonth() ? mSchemeTextPaint : mOtherMonthTextPaint);

    } else {
        canvas.drawText(calendar.isCurrentDay() ? "今" : String.valueOf(calendar.getDay()),
                cx,
                baselineY,
                calendar.isCurrentDay() ? mCurDayTextPaint :
                        calendar.isCurrentMonth() ? mCurMonthTextPaint : mOtherMonthTextPaint);
    }

    //日期是否可用？拦截
    if (onCalendarIntercept(calendar)) {
        canvas.drawLine(x + mH, mH, x + mItemWidth - mH, mItemHeight - mH, mDisablePaint);
    }
}
 

@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);

    // 绘制圆
    canvas.drawCircle(mCircleXY, mCircleXY, mRadius, mCirclePaint);
    // 绘制弧线
    canvas.drawArc(mArcRectF, 270, mSweepAngle, false,mArcPaint);
    // 绘制文字
    canvas.drawText(mShowText, 0, mShowText.length(),mCircleXY, mCircleXY + (mShowTextSize / 4),mTextPaint);
}
 

public static boolean isLangSupported(Context context, String text) {
    int sdk = android.os.Build.VERSION.SDK_INT;
    int w = 200, h = 80;
    Resources resources = context.getResources();
    float scale = resources.getDisplayMetrics().density;
    Bitmap.Config conf = Bitmap.Config.ARGB_8888;
    Bitmap bitmap = Bitmap.createBitmap(w, h, conf); // this creates a MUTABLE bitmap
    Bitmap orig = bitmap.copy(conf, false);
    Canvas canvas = new Canvas(bitmap);
    Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
    paint.setColor(Color.rgb(0, 0, 0));
    paint.setTextSize((int) (14 * scale));

    // draw text to the Canvas center
    Rect bounds = new Rect();
    paint.getTextBounds(text, 0, text.length(), bounds);
    int x = (bitmap.getWidth() - bounds.width()) / 2;
    int y = (bitmap.getHeight() + bounds.height()) / 2;

    canvas.drawText(text, x, y, paint);
    boolean res = false;
    if (sdk < android.os.Build.VERSION_CODES.HONEYCOMB) {
        res = !(orig == bitmap);
    } else {
        res = !orig.sameAs(bitmap);
    }
    orig.recycle();
    bitmap.recycle();
    return res;
}
 

static Bitmap createRoundIconWithText(Context context, String letter) {

        //calculate dimensions
        //-1 to take into account the shadow layer
        int w = (int) context.getResources().getDimension(android.R.dimen.app_icon_size);
        int h = (int) context.getResources().getDimension(android.R.dimen.app_icon_size);
        int r = w / 2 - 1;

        //create bitmap
        Bitmap b = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);

        //draw a circle of the same dimensions
        Canvas canvas = new Canvas(b);
        Paint paint = new Paint();
        int color = ContextCompat.getColor(context, getRandom(SolidWallpaperUtils.material_colors));
        paint.setColor(color);

        final int SHADOW_COLOR = 0x80000000;
        paint.setShadowLayer(0.5f, 1, 1, SHADOW_COLOR);
        paint.setAntiAlias(true);
        canvas.drawCircle(r, r, r, paint);

        Paint textPaint = new Paint();
        textPaint.setColor(Utilities.getComplementaryColor(color));
        textPaint.setTextAlign(Paint.Align.CENTER);
        textPaint.setTextSize(w / 2);

        textPaint.setAntiAlias(true);
        textPaint.setTypeface(Typeface.SANS_SERIF);
        int xPos = (canvas.getWidth() / 2);
        int yPos = (int) ((canvas.getHeight() / 2) - ((textPaint.descent() + textPaint.ascent()) / 2));

        canvas.drawText(letter, xPos, yPos, textPaint);

        return b;
    }
 

public void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    int centre = getWidth() / 2;
    int radius = (int) (((float) centre) - (this.roundWidth / 2.0f));
    this.paint.setColor(this.roundColor);
    this.paint.setStyle(Style.STROKE);
    this.paint.setStrokeWidth(this.roundWidth);
    this.paint.setAntiAlias(true);
    canvas.drawCircle((float) centre, (float) centre, (float) radius, this.paint);
    this.paint.setStrokeWidth(0.0f);
    this.paint.setColor(this.textColor);
    this.paint.setTextSize(this.textSize);
    this.paint.setStrokeCap(Cap.ROUND);
    this.paint.setTypeface(Typeface.DEFAULT_BOLD);
    int percent = (int) ((((float) this.progress) / ((float) this.max)) * 100.0f);
    float textWidth = this.paint.measureText(percent + "%");
    if (this.textIsDisplayable && this.style == 0) {
        canvas.drawText(percent + "%", ((float) centre) - (textWidth / 2.0f), ((float) centre) + (this.textSize / 2.0f), this.paint);
    }
    this.paint.setStrokeWidth(this.roundWidthPlan);
    this.paint.setColor(this.roundProgressColor);
    RectF oval = new RectF((float) (centre - radius), (float) (centre - radius), (float) (centre + radius), (float) (centre + radius));
    switch (this.style) {
        case 0:
            this.paint.setStyle(Style.STROKE);
            canvas.drawArc(oval, 270.0f, (float) ((this.progress * 360) / this.max), false, this.paint);
            return;
        case 1:
            this.paint.setStyle(Style.FILL_AND_STROKE);
            if (this.progress != 0) {
                canvas.drawArc(oval, 270.0f, (float) ((this.progress * 360) / this.max), true, this.paint);
                return;
            }
            return;
        default:
            return;
    }
}
 

@Override
public void drawMonthDay(Canvas canvas, int year, int month, int day,
        int x, int y, int startX, int stopX, int startY, int stopY) {
    if (mSelectedDay == day) {
        canvas.drawCircle(x , y - (MINI_DAY_NUMBER_TEXT_SIZE / 3), DAY_SELECTED_CIRCLE_SIZE,
                mSelectedCirclePaint);
    }

    if (mHasToday && mToday == day) {
        mMonthNumPaint.setColor(mTodayNumberColor);
    } else {
        mMonthNumPaint.setColor(mDayTextColor);
    }
    canvas.drawText(String.format("%d", day), x, y, mMonthNumPaint);
}
 

@Override
public void onDraw(Canvas canvas) {
    int viewWidth = getWidth();
    if (viewWidth == 0 || !mIsInitialized) {
        return;
    }

    if (!mDrawValuesReady) {
        int layoutXCenter = getWidth() / 2;
        int layoutYCenter = getHeight() / 2;
        int circleRadius =
                (int) (Math.min(layoutXCenter, layoutYCenter) * mCircleRadiusMultiplier);
        mAmPmCircleRadius = (int) (circleRadius * mAmPmCircleRadiusMultiplier);
        layoutYCenter += mAmPmCircleRadius*0.75;
        int textSize = mAmPmCircleRadius * 3 / 4;
        mPaint.setTextSize(textSize);

        // Line up the vertical center of the AM/PM circles with the bottom of the main circle.
        mAmPmYCenter = layoutYCenter - mAmPmCircleRadius / 2 + circleRadius;
        // Line up the horizontal edges of the AM/PM circles with the horizontal edges
        // of the main circle.
        mAmXCenter = layoutXCenter - circleRadius + mAmPmCircleRadius;
        mPmXCenter = layoutXCenter + circleRadius - mAmPmCircleRadius;

        mDrawValuesReady = true;
    }

    // We'll need to draw either a lighter blue (for selection), a darker blue (for touching)
    // or white (for not selected).
    int amColor = mUnselectedColor;
    int amAlpha = 255;
    int amTextColor = mAmPmTextColor;
    int pmColor = mUnselectedColor;
    int pmAlpha = 255;
    int pmTextColor = mAmPmTextColor;

    if (mAmOrPm == AM) {
        amColor = mSelectedColor;
        amAlpha = mSelectedAlpha;
        amTextColor = mAmPmSelectedTextColor;
    } else if (mAmOrPm == PM) {
        pmColor = mSelectedColor;
        pmAlpha = mSelectedAlpha;
        pmTextColor = mAmPmSelectedTextColor;
    }
    if (mAmOrPmPressed == AM) {
        amColor = mTouchedColor;
        amAlpha = mSelectedAlpha;
    } else if (mAmOrPmPressed == PM) {
        pmColor = mTouchedColor;
        pmAlpha = mSelectedAlpha;
    }
    if (mAmDisabled) {
        amColor = mUnselectedColor;
        amTextColor = mAmPmDisabledTextColor;
    }
    if (mPmDisabled) {
        pmColor = mUnselectedColor;
        pmTextColor = mAmPmDisabledTextColor;
    }

    // Draw the two circles.
    mPaint.setColor(amColor);
    mPaint.setAlpha(amAlpha);
    canvas.drawCircle(mAmXCenter, mAmPmYCenter, mAmPmCircleRadius, mPaint);
    mPaint.setColor(pmColor);
    mPaint.setAlpha(pmAlpha);
    canvas.drawCircle(mPmXCenter, mAmPmYCenter, mAmPmCircleRadius, mPaint);

    // Draw the AM/PM texts on top.
    mPaint.setColor(amTextColor);
    int textYCenter = mAmPmYCenter - (int) (mPaint.descent() + mPaint.ascent()) / 2;
    canvas.drawText(mAmText, mAmXCenter, textYCenter, mPaint);
    mPaint.setColor(pmTextColor);
    canvas.drawText(mPmText, mPmXCenter, textYCenter, mPaint);
}
 

public void draw(Canvas canvas) {
    if (mState == STATE_HIDDEN)
        return;

    // mAlphaRate determines the rate of opacity
    mIndexBarPaint.setColor(Color.BLACK);
    mIndexBarPaint.setAlpha((int) (64 * mAlphaRate));
    mIndexBarPaint.setAntiAlias(true);
    canvas.drawRoundRect(mIndexbarRect, 5 * mDensity, 5 * mDensity, mIndexBarPaint);

    if (mSections != null && mSections.size() > 0) {
        // Preview is shown when mCurrentSection is set
        if (mCurrentSection >= 0) {
            mPreviewPaint.setColor(Color.BLACK);
            mPreviewPaint.setAlpha(96);
            mPreviewPaint.setAntiAlias(true);
            mPreviewPaint.setShadowLayer(3, 0, 0, Color.argb(64, 0, 0, 0));

            mPreviewTextPaint.setColor(Color.WHITE);
            mPreviewTextPaint.setAntiAlias(true);
            mPreviewTextPaint.setTextSize(50 * mScaledDensity);

            float previewTextWidth = mPreviewTextPaint.measureText(mSections.get(mCurrentSection));
            float previewSize = 2 * mPreviewPadding + mPreviewTextPaint.descent() - mPreviewTextPaint.ascent();
            mPreviewRect.set((mListViewWidth - previewSize) / 2
                    , (mListViewHeight - previewSize) / 2
                    , (mListViewWidth - previewSize) / 2 + previewSize
                    , (mListViewHeight - previewSize) / 2 + previewSize);

            canvas.drawRoundRect(mPreviewRect, 5 * mDensity, 5 * mDensity, mPreviewPaint);
            canvas.drawText(mSections.get(mCurrentSection), mPreviewRect.left + (previewSize - previewTextWidth) / 2 - 1
                    , mPreviewRect.top + mPreviewPadding - mPreviewTextPaint.ascent() + 1, mPreviewTextPaint);
        }

        mIndexPaint.setColor(Color.WHITE);
        mIndexPaint.setAlpha((int) (255 * mAlphaRate));
        mIndexPaint.setAntiAlias(true);
        mIndexPaint.setTextSize(12 * mScaledDensity);

        float sectionHeight = (mIndexbarRect.height() - 2 * mIndexbarMargin) / mSections.size();
        float paddingTop = (sectionHeight - (mIndexPaint.descent() - mIndexPaint.ascent())) / 2;
        for (int i = 0; i < mSections.size(); i++) {
            float paddingLeft = (mIndexbarWidth - mIndexPaint.measureText(mSections.get(i))) / 2;
            canvas.drawText(mSections.get(i), mIndexbarRect.left + paddingLeft
                    , mIndexbarRect.top + mIndexbarMargin + sectionHeight * i + paddingTop - mIndexPaint.ascent(), mIndexPaint);
        }
    }
}
 

@Override
public void invalidate() {
    super.invalidate();

    final SurfaceHolder holder = mHolder;
    if (holder == null) {
        return;
    }

    final Canvas canvas = holder.lockCanvas();
    if (canvas == null) {
        return;
    }

    // Clear the canvas.
    canvas.drawColor(Color.TRANSPARENT, Mode.CLEAR);

    if (getVisibility() != View.VISIBLE) {
        holder.unlockCanvasAndPost(canvas);
        return;
    }

    final int width = getWidth();
    final int height = getHeight();

    // Draw the pretty gradient background.
    mGradientBackground.setBounds(0, 0, width, height);
    mGradientBackground.draw(canvas);

    Paint paint = new Paint();
    paint.setColor(Color.WHITE);
    paint.setStyle(Style.FILL);
    paint.setTextAlign(Align.CENTER);
    paint.setTextSize(mContext.getResources().getDimensionPixelSize(
            R.dimen.search_text_font_size));
    canvas.drawText(
            mContext.getString(R.string.search_dialog_label, mQueryText),
            width / 2.0f,
            height / 2.0f,
            paint);

    holder.unlockCanvasAndPost(canvas);
}
 

@Override
public void draw(@NonNull Canvas canvas) {
    mPaint.setColor(Color.BLACK);
    canvas.drawText("IMAGE", 30f, 30f, mPaint);
}
 

public void draw(Canvas canvas) {
    final int saveCount = canvas.save();

    if (mTextToDraw != null && mDrawTitle) {
        float x = mCurrentDrawX;
        float y = mCurrentDrawY;

        final boolean drawTexture = mUseTexture && mExpandedTitleTexture != null;

        final float ascent;
        final float descent;
        if (drawTexture) {
            ascent = mTextureAscent * mScale;
            descent = mTextureDescent * mScale;
        } else {
            ascent = mTextPaint.ascent() * mScale;
            descent = mTextPaint.descent() * mScale;
        }

        if (DEBUG_DRAW) {
            // Just a debug tool, which drawn a magenta rect in the text bounds
            canvas.drawRect(mCurrentBounds.left, y + ascent, mCurrentBounds.right, y + descent,
                    DEBUG_DRAW_PAINT);
        }

        if (drawTexture) {
            y += ascent;
        }

        if (mScale != 1f) {
            canvas.scale(mScale, mScale, x, y);
        }

        if (drawTexture) {
            // If we should use a texture, draw it instead of text
            canvas.drawBitmap(mExpandedTitleTexture, x, y, mTexturePaint);
        } else {
            canvas.drawText(mTextToDraw, 0, mTextToDraw.length(), x, y, mTextPaint);
        }
    }

    canvas.restoreToCount(saveCount);
}
 

@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);

    //这里的矩阵是相对于Paint将要绘制的区域的（还是View?）
    //一定要reset或setscale
    mWaveShaderMatrix.reset();
    //根据用户的设置的波长以及振幅比例缩放
    mWaveShaderMatrix.postScale(mWaveLengthRatio, mWaveAmplitudeRatio, 0, mDefaultWaveHeight);
    //平移Shader产生动画效果
    mWaveShaderMatrix.postTranslate(mAwayLeftRatio * getMeasuredWidth() * mWaveLengthRatio
            , (0.5f - mWaveHeightRatio) * getHeight());
    //确定最终效果
    mWaveShader.setLocalMatrix(mWaveShaderMatrix);

    float borderWidth = mBorderPaint.getStrokeWidth();

    /*CIRCLE,SQUARE,RECTANGLE*/
    switch (mType){
        //圆
        case 0:
            //绘制
            int radius = Math.min(getWidth(), getHeight()) / 2;

            if(borderWidth > 0){
                mBorderPaint.setColor(mWaveColor);
                canvas.drawCircle(radius, radius, (2 * radius - borderWidth) / 2f - 1f, mBorderPaint);
            }
            canvas.drawCircle(radius, radius, radius, mWavePaint);

            break;
        //正方形
        case 1:
            if(borderWidth > 0){
                canvas.drawRect(
                        borderWidth / 2f,
                        borderWidth / 2f,
                        Math.min(getWidth(), getHeight()) - borderWidth / 2f - 0.5f,
                        Math.min(getWidth(), getHeight()) - borderWidth / 2f - 0.5f,
                        mBorderPaint);
            }
            canvas.drawRect(borderWidth
                    , borderWidth
                    , Math.min(getWidth(), getHeight()) - borderWidth
                    , Math.min(getWidth(), getHeight()) - borderWidth
                    , mWavePaint);
            break;
        //长方形
        //不太好看
        /*case 2:
            if(borderWidth > 0){
                canvas.drawRect(borderWidth / 2f,
                        borderWidth / 2f,
                        getWidth() - borderWidth / 2f - 0.5f,
                        getHeight() - borderWidth / 2f - 0.5f,
                        mBorderPaint);
            }
            canvas.drawRect(borderWidth
                    , borderWidth
                    , getWidth() - borderWidth
                    , getHeight() - borderWidth
                    , mWavePaint);
            break;*/
    }

    float textWidth = mTitlePaint.measureText(mTitletext);
    canvas.drawText(mTitletext
            , (getWidth() - textWidth) / 2
            , getHeight() / 2 - (mTitlePaint.descent() + mTitlePaint.ascent()) / 2
            , mTitlePaint);


}
 

/**
 * Draws the provided label at the given position.
 *
 * @param c     canvas to draw with
 * @param x
 * @param y
 * @param label the label to draw
 */
protected void drawLabel(Canvas c, float x, float y, String label) {
    c.drawText(label, x, y, mLegendLabelPaint);
}