core/java/com/android/internal/widget/SubtitleView.java - platform/frameworks/base - Git at Google

 /*
  * Copyright (C) 2013 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package com.android.internal.widget;

 import android.content.ContentResolver;
 import android.content.Context;
 import android.content.res.Resources;
 import android.content.res.TypedArray;
 import android.graphics.Canvas;
 import android.graphics.Color;
 import android.graphics.Paint;
 import android.graphics.Paint.Join;
 import android.graphics.Paint.Style;
 import android.graphics.RectF;
 import android.graphics.Typeface;
 import android.text.Layout.Alignment;
 import android.text.StaticLayout;
 import android.text.TextPaint;
 import android.util.AttributeSet;
 import android.view.View;
 import android.view.accessibility.CaptioningManager.CaptionStyle;

 public class SubtitleView extends View {
     // Ratio of inner padding to font size.
     private static final float INNER_PADDING_RATIO = 0.125f;

     /** Color used for the shadowed edge of a bevel. */
     private static final int COLOR_BEVEL_DARK = 0x80000000;

     /** Color used for the illuminated edge of a bevel. */
     private static final int COLOR_BEVEL_LIGHT = 0x80FFFFFF;

     // Styled dimensions.
     private final float mCornerRadius;
     private final float mOutlineWidth;
     private final float mShadowRadius;
     private final float mShadowOffsetX;
     private final float mShadowOffsetY;

     /** Temporary rectangle used for computing line bounds. */
     private final RectF mLineBounds = new RectF();

     /** Reusable string builder used for holding text. */
     private final StringBuilder mText = new StringBuilder();

     private Alignment mAlignment;
     private TextPaint mTextPaint;
     private Paint mPaint;

     private int mForegroundColor;
     private int mBackgroundColor;
     private int mEdgeColor;
     private int mEdgeType;

     private boolean mHasMeasurements;
     private int mLastMeasuredWidth;
     private StaticLayout mLayout;

     private float mSpacingMult = 1;
     private float mSpacingAdd = 0;
     private int mInnerPaddingX = 0;

     public SubtitleView(Context context) {
         this(context, null);
     }

     public SubtitleView(Context context, AttributeSet attrs) {
         this(context, attrs, 0);
     }

     public SubtitleView(Context context, AttributeSet attrs, int defStyleAttr) {
         this(context, attrs, defStyleAttr, 0);
     }

     public SubtitleView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
         super(context, attrs);

         final TypedArray a = context.obtainStyledAttributes(
                     attrs, android.R.styleable.TextView, defStyleAttr, defStyleRes);

         CharSequence text = "";
         int textSize = 15;

         final int n = a.getIndexCount();
         for (int i = 0; i < n; i++) {
             int attr = a.getIndex(i);

             switch (attr) {
                 case android.R.styleable.TextView_text:
                     text = a.getText(attr);
                     break;
                 case android.R.styleable.TextView_lineSpacingExtra:
                     mSpacingAdd = a.getDimensionPixelSize(attr, (int) mSpacingAdd);
                     break;
                 case android.R.styleable.TextView_lineSpacingMultiplier:
                     mSpacingMult = a.getFloat(attr, mSpacingMult);
                     break;
                 case android.R.styleable.TextAppearance_textSize:
                     textSize = a.getDimensionPixelSize(attr, textSize);
                     break;
             }
         }

         // Set up density-dependent properties.
         // TODO: Move these to a default style.
         final Resources res = getContext().getResources();
         mCornerRadius = res.getDimensionPixelSize(com.android.internal.R.dimen.subtitle_corner_radius);
         mOutlineWidth = res.getDimensionPixelSize(com.android.internal.R.dimen.subtitle_outline_width);
         mShadowRadius = res.getDimensionPixelSize(com.android.internal.R.dimen.subtitle_shadow_radius);
         mShadowOffsetX = res.getDimensionPixelSize(com.android.internal.R.dimen.subtitle_shadow_offset);
         mShadowOffsetY = mShadowOffsetX;

         mTextPaint = new TextPaint();
         mTextPaint.setAntiAlias(true);
         mTextPaint.setSubpixelText(true);

         mPaint = new Paint();
         mPaint.setAntiAlias(true);

         setText(text);
         setTextSize(textSize);
     }

     public void setText(int resId) {
         final CharSequence text = getContext().getText(resId);
         setText(text);
     }

     public void setText(CharSequence text) {
         mText.setLength(0);
         mText.append(text);

         mHasMeasurements = false;

         requestLayout();
         invalidate();
     }

     public void setForegroundColor(int color) {
         mForegroundColor = color;

         invalidate();
     }

     @Override
     public void setBackgroundColor(int color) {
         mBackgroundColor = color;

         invalidate();
     }

     public void setEdgeType(int edgeType) {
         mEdgeType = edgeType;

         invalidate();
     }

     public void setEdgeColor(int color) {
         mEdgeColor = color;

         invalidate();
     }

     /**
      * Sets the text size in pixels.
      *
      * @param size the text size in pixels
      */
     public void setTextSize(float size) {
         if (mTextPaint.getTextSize() != size) {
             mTextPaint.setTextSize(size);
             mInnerPaddingX = (int) (size * INNER_PADDING_RATIO + 0.5f);

             mHasMeasurements = false;

             requestLayout();
             invalidate();
         }
     }

     public void setTypeface(Typeface typeface) {
         if (mTextPaint.getTypeface() != typeface) {
             mTextPaint.setTypeface(typeface);

             mHasMeasurements = false;

             requestLayout();
             invalidate();
         }
     }

     public void setAlignment(Alignment textAlignment) {
         if (mAlignment != textAlignment) {
             mAlignment = textAlignment;

             mHasMeasurements = false;

             requestLayout();
             invalidate();
         }
     }

     @Override
     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
         final int widthSpec = MeasureSpec.getSize(widthMeasureSpec);

         if (computeMeasurements(widthSpec)) {
             final StaticLayout layout = mLayout;

             // Account for padding.
             final int paddingX = mPaddingLeft + mPaddingRight + mInnerPaddingX * 2;
             final int width = layout.getWidth() + paddingX;
             final int height = layout.getHeight() + mPaddingTop + mPaddingBottom;
             setMeasuredDimension(width, height);
         } else {
             setMeasuredDimension(MEASURED_STATE_TOO_SMALL, MEASURED_STATE_TOO_SMALL);
         }
     }

     @Override
     public void onLayout(boolean changed, int l, int t, int r, int b) {
         final int width = r - l;

         computeMeasurements(width);
     }

     private boolean computeMeasurements(int maxWidth) {
         if (mHasMeasurements && maxWidth == mLastMeasuredWidth) {
             return true;
         }

         // Account for padding.
         final int paddingX = mPaddingLeft + mPaddingRight + mInnerPaddingX * 2;
         maxWidth -= paddingX;
         if (maxWidth <= 0) {
             return false;
         }

         // TODO: Implement minimum-difference line wrapping. Adding the results
         // of Paint.getTextWidths() seems to return different values than
         // StaticLayout.getWidth(), so this is non-trivial.
         mHasMeasurements = true;
         mLastMeasuredWidth = maxWidth;
         mLayout = new StaticLayout(
                 mText, mTextPaint, maxWidth, mAlignment, mSpacingMult, mSpacingAdd, true);

         return true;
     }

     public void setStyle(int styleId) {
         final Context context = mContext;
         final ContentResolver cr = context.getContentResolver();
         final CaptionStyle style;
         if (styleId == CaptionStyle.PRESET_CUSTOM) {
             style = CaptionStyle.getCustomStyle(cr);
         } else {
             style = CaptionStyle.PRESETS[styleId];
         }

         final CaptionStyle defStyle = CaptionStyle.DEFAULT;
         mForegroundColor = style.hasForegroundColor() ?
                 style.foregroundColor : defStyle.foregroundColor;
         mBackgroundColor = style.hasBackgroundColor() ?
                 style.backgroundColor : defStyle.backgroundColor;
         mEdgeType = style.hasEdgeType() ? style.edgeType : defStyle.edgeType;
         mEdgeColor = style.hasEdgeColor() ? style.edgeColor : defStyle.edgeColor;
         mHasMeasurements = false;

         final Typeface typeface = style.getTypeface();
         setTypeface(typeface);

         requestLayout();
     }

     @Override
     protected void onDraw(Canvas c) {
         final StaticLayout layout = mLayout;
         if (layout == null) {
             return;
         }

         final int saveCount = c.save();
         final int innerPaddingX = mInnerPaddingX;
         c.translate(mPaddingLeft + innerPaddingX, mPaddingTop);

         final int lineCount = layout.getLineCount();
         final Paint textPaint = mTextPaint;
         final Paint paint = mPaint;
         final RectF bounds = mLineBounds;

         if (Color.alpha(mBackgroundColor) > 0) {
             final float cornerRadius = mCornerRadius;
             float previousBottom = layout.getLineTop(0);

             paint.setColor(mBackgroundColor);
             paint.setStyle(Style.FILL);

             for (int i = 0; i < lineCount; i++) {
                 bounds.left = layout.getLineLeft(i) -innerPaddingX;
                 bounds.right = layout.getLineRight(i) + innerPaddingX;
                 bounds.top = previousBottom;
                 bounds.bottom = layout.getLineBottom(i);
                 previousBottom = bounds.bottom;

                 c.drawRoundRect(bounds, cornerRadius, cornerRadius, paint);
             }
         }

         final int edgeType = mEdgeType;
         if (edgeType == CaptionStyle.EDGE_TYPE_OUTLINE) {
             textPaint.setStrokeJoin(Join.ROUND);
             textPaint.setStrokeWidth(mOutlineWidth);
             textPaint.setColor(mEdgeColor);
             textPaint.setStyle(Style.FILL_AND_STROKE);

             for (int i = 0; i < lineCount; i++) {
                 layout.drawText(c, i, i);
             }
         } else if (edgeType == CaptionStyle.EDGE_TYPE_DROP_SHADOW) {
             textPaint.setShadowLayer(mShadowRadius, mShadowOffsetX, mShadowOffsetY, mEdgeColor);
         } else if (edgeType == CaptionStyle.EDGE_TYPE_RAISED
                 || edgeType == CaptionStyle.EDGE_TYPE_DEPRESSED) {
             final boolean raised = edgeType == CaptionStyle.EDGE_TYPE_RAISED;
             final int colorUp = raised ? Color.WHITE : mEdgeColor;
             final int colorDown = raised ? mEdgeColor : Color.WHITE;
             final float offset = mShadowRadius / 2f;

             textPaint.setColor(mForegroundColor);
             textPaint.setStyle(Style.FILL);
             textPaint.setShadowLayer(mShadowRadius, -offset, -offset, colorUp);

             for (int i = 0; i < lineCount; i++) {
                 layout.drawText(c, i, i);
             }

             textPaint.setShadowLayer(mShadowRadius, offset, offset, colorDown);
         }

         textPaint.setColor(mForegroundColor);
         textPaint.setStyle(Style.FILL);

         for (int i = 0; i < lineCount; i++) {
             layout.drawText(c, i, i);
         }

         textPaint.setShadowLayer(0, 0, 0, 0);
         c.restoreToCount(saveCount);
     }
 }
	/*
	* Copyright (C) 2013 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.android.internal.widget;

	import android.content.ContentResolver;
	import android.content.Context;
	import android.content.res.Resources;
	import android.content.res.TypedArray;
	import android.graphics.Canvas;
	import android.graphics.Color;
	import android.graphics.Paint;
	import android.graphics.Paint.Join;
	import android.graphics.Paint.Style;
	import android.graphics.RectF;
	import android.graphics.Typeface;
	import android.text.Layout.Alignment;
	import android.text.StaticLayout;
	import android.text.TextPaint;
	import android.util.AttributeSet;
	import android.view.View;
	import android.view.accessibility.CaptioningManager.CaptionStyle;

	public class SubtitleView extends View {
	// Ratio of inner padding to font size.
	private static final float INNER_PADDING_RATIO = 0.125f;

	/** Color used for the shadowed edge of a bevel. */
	private static final int COLOR_BEVEL_DARK = 0x80000000;

	/** Color used for the illuminated edge of a bevel. */
	private static final int COLOR_BEVEL_LIGHT = 0x80FFFFFF;

	// Styled dimensions.
	private final float mCornerRadius;
	private final float mOutlineWidth;
	private final float mShadowRadius;
	private final float mShadowOffsetX;
	private final float mShadowOffsetY;

	/** Temporary rectangle used for computing line bounds. */
	private final RectF mLineBounds = new RectF();

	/** Reusable string builder used for holding text. */
	private final StringBuilder mText = new StringBuilder();

	private Alignment mAlignment;
	private TextPaint mTextPaint;
	private Paint mPaint;

	private int mForegroundColor;
	private int mBackgroundColor;
	private int mEdgeColor;
	private int mEdgeType;

	private boolean mHasMeasurements;
	private int mLastMeasuredWidth;
	private StaticLayout mLayout;

	private float mSpacingMult = 1;
	private float mSpacingAdd = 0;
	private int mInnerPaddingX = 0;

	public SubtitleView(Context context) {
	this(context, null);
	}

	public SubtitleView(Context context, AttributeSet attrs) {
	this(context, attrs, 0);
	}

	public SubtitleView(Context context, AttributeSet attrs, int defStyleAttr) {
	this(context, attrs, defStyleAttr, 0);
	}

	public SubtitleView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
	super(context, attrs);

	final TypedArray a = context.obtainStyledAttributes(
	attrs, android.R.styleable.TextView, defStyleAttr, defStyleRes);

	CharSequence text = "";
	int textSize = 15;

	final int n = a.getIndexCount();
	for (int i = 0; i < n; i++) {
	int attr = a.getIndex(i);

	switch (attr) {
	case android.R.styleable.TextView_text:
	text = a.getText(attr);
	break;
	case android.R.styleable.TextView_lineSpacingExtra:
	mSpacingAdd = a.getDimensionPixelSize(attr, (int) mSpacingAdd);
	break;
	case android.R.styleable.TextView_lineSpacingMultiplier:
	mSpacingMult = a.getFloat(attr, mSpacingMult);
	break;
	case android.R.styleable.TextAppearance_textSize:
	textSize = a.getDimensionPixelSize(attr, textSize);
	break;
	}
	}

	// Set up density-dependent properties.
	// TODO: Move these to a default style.
	final Resources res = getContext().getResources();
	mCornerRadius = res.getDimensionPixelSize(com.android.internal.R.dimen.subtitle_corner_radius);
	mOutlineWidth = res.getDimensionPixelSize(com.android.internal.R.dimen.subtitle_outline_width);
	mShadowRadius = res.getDimensionPixelSize(com.android.internal.R.dimen.subtitle_shadow_radius);
	mShadowOffsetX = res.getDimensionPixelSize(com.android.internal.R.dimen.subtitle_shadow_offset);
	mShadowOffsetY = mShadowOffsetX;

	mTextPaint = new TextPaint();
	mTextPaint.setAntiAlias(true);
	mTextPaint.setSubpixelText(true);

	mPaint = new Paint();
	mPaint.setAntiAlias(true);

	setText(text);
	setTextSize(textSize);
	}

	public void setText(int resId) {
	final CharSequence text = getContext().getText(resId);
	setText(text);
	}

	public void setText(CharSequence text) {
	mText.setLength(0);
	mText.append(text);

	mHasMeasurements = false;

	requestLayout();
	invalidate();
	}

	public void setForegroundColor(int color) {
	mForegroundColor = color;

	invalidate();
	}

	@Override
	public void setBackgroundColor(int color) {
	mBackgroundColor = color;

	invalidate();
	}

	public void setEdgeType(int edgeType) {
	mEdgeType = edgeType;

	invalidate();
	}

	public void setEdgeColor(int color) {
	mEdgeColor = color;

	invalidate();
	}

	/**
	* Sets the text size in pixels.
	*
	* @param size the text size in pixels
	*/
	public void setTextSize(float size) {
	if (mTextPaint.getTextSize() != size) {
	mTextPaint.setTextSize(size);
	mInnerPaddingX = (int) (size * INNER_PADDING_RATIO + 0.5f);

	mHasMeasurements = false;

	requestLayout();
	invalidate();
	}
	}

	public void setTypeface(Typeface typeface) {
	if (mTextPaint.getTypeface() != typeface) {
	mTextPaint.setTypeface(typeface);

	mHasMeasurements = false;

	requestLayout();
	invalidate();
	}
	}

	public void setAlignment(Alignment textAlignment) {
	if (mAlignment != textAlignment) {
	mAlignment = textAlignment;

	mHasMeasurements = false;

	requestLayout();
	invalidate();
	}
	}

	@Override
	protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
	final int widthSpec = MeasureSpec.getSize(widthMeasureSpec);

	if (computeMeasurements(widthSpec)) {
	final StaticLayout layout = mLayout;

	// Account for padding.
	final int paddingX = mPaddingLeft + mPaddingRight + mInnerPaddingX * 2;
	final int width = layout.getWidth() + paddingX;
	final int height = layout.getHeight() + mPaddingTop + mPaddingBottom;
	setMeasuredDimension(width, height);
	} else {
	setMeasuredDimension(MEASURED_STATE_TOO_SMALL, MEASURED_STATE_TOO_SMALL);
	}
	}

	@Override
	public void onLayout(boolean changed, int l, int t, int r, int b) {
	final int width = r - l;

	computeMeasurements(width);
	}

	private boolean computeMeasurements(int maxWidth) {
	if (mHasMeasurements && maxWidth == mLastMeasuredWidth) {
	return true;
	}

	// Account for padding.
	final int paddingX = mPaddingLeft + mPaddingRight + mInnerPaddingX * 2;
	maxWidth -= paddingX;
	if (maxWidth <= 0) {
	return false;
	}

	// TODO: Implement minimum-difference line wrapping. Adding the results
	// of Paint.getTextWidths() seems to return different values than
	// StaticLayout.getWidth(), so this is non-trivial.
	mHasMeasurements = true;
	mLastMeasuredWidth = maxWidth;
	mLayout = new StaticLayout(
	mText, mTextPaint, maxWidth, mAlignment, mSpacingMult, mSpacingAdd, true);

	return true;
	}

	public void setStyle(int styleId) {
	final Context context = mContext;
	final ContentResolver cr = context.getContentResolver();
	final CaptionStyle style;
	if (styleId == CaptionStyle.PRESET_CUSTOM) {
	style = CaptionStyle.getCustomStyle(cr);
	} else {
	style = CaptionStyle.PRESETS[styleId];
	}

	final CaptionStyle defStyle = CaptionStyle.DEFAULT;
	mForegroundColor = style.hasForegroundColor() ?
	style.foregroundColor : defStyle.foregroundColor;
	mBackgroundColor = style.hasBackgroundColor() ?
	style.backgroundColor : defStyle.backgroundColor;
	mEdgeType = style.hasEdgeType() ? style.edgeType : defStyle.edgeType;
	mEdgeColor = style.hasEdgeColor() ? style.edgeColor : defStyle.edgeColor;
	mHasMeasurements = false;

	final Typeface typeface = style.getTypeface();
	setTypeface(typeface);

	requestLayout();
	}

	@Override
	protected void onDraw(Canvas c) {
	final StaticLayout layout = mLayout;
	if (layout == null) {
	return;
	}

	final int saveCount = c.save();
	final int innerPaddingX = mInnerPaddingX;
	c.translate(mPaddingLeft + innerPaddingX, mPaddingTop);

	final int lineCount = layout.getLineCount();
	final Paint textPaint = mTextPaint;
	final Paint paint = mPaint;
	final RectF bounds = mLineBounds;

	if (Color.alpha(mBackgroundColor) > 0) {
	final float cornerRadius = mCornerRadius;
	float previousBottom = layout.getLineTop(0);

	paint.setColor(mBackgroundColor);
	paint.setStyle(Style.FILL);

	for (int i = 0; i < lineCount; i++) {
	bounds.left = layout.getLineLeft(i) -innerPaddingX;
	bounds.right = layout.getLineRight(i) + innerPaddingX;
	bounds.top = previousBottom;
	bounds.bottom = layout.getLineBottom(i);
	previousBottom = bounds.bottom;

	c.drawRoundRect(bounds, cornerRadius, cornerRadius, paint);
	}
	}

	final int edgeType = mEdgeType;
	if (edgeType == CaptionStyle.EDGE_TYPE_OUTLINE) {
	textPaint.setStrokeJoin(Join.ROUND);
	textPaint.setStrokeWidth(mOutlineWidth);
	textPaint.setColor(mEdgeColor);
	textPaint.setStyle(Style.FILL_AND_STROKE);

	for (int i = 0; i < lineCount; i++) {
	layout.drawText(c, i, i);
	}
	} else if (edgeType == CaptionStyle.EDGE_TYPE_DROP_SHADOW) {
	textPaint.setShadowLayer(mShadowRadius, mShadowOffsetX, mShadowOffsetY, mEdgeColor);
	} else if (edgeType == CaptionStyle.EDGE_TYPE_RAISED
	\|\| edgeType == CaptionStyle.EDGE_TYPE_DEPRESSED) {
	final boolean raised = edgeType == CaptionStyle.EDGE_TYPE_RAISED;
	final int colorUp = raised ? Color.WHITE : mEdgeColor;
	final int colorDown = raised ? mEdgeColor : Color.WHITE;
	final float offset = mShadowRadius / 2f;

	textPaint.setColor(mForegroundColor);
	textPaint.setStyle(Style.FILL);
	textPaint.setShadowLayer(mShadowRadius, -offset, -offset, colorUp);

	for (int i = 0; i < lineCount; i++) {
	layout.drawText(c, i, i);
	}

	textPaint.setShadowLayer(mShadowRadius, offset, offset, colorDown);
	}

	textPaint.setColor(mForegroundColor);
	textPaint.setStyle(Style.FILL);

	for (int i = 0; i < lineCount; i++) {
	layout.drawText(c, i, i);
	}

	textPaint.setShadowLayer(0, 0, 0, 0);
	c.restoreToCount(saveCount);
	}
	}