| /* |
| * Copyright (C) 2006 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 android.text.style; |
| |
| import android.annotation.ColorInt; |
| import android.annotation.NonNull; |
| import android.annotation.Px; |
| import android.graphics.Canvas; |
| import android.graphics.Paint; |
| import android.os.Parcel; |
| import android.text.ParcelableSpan; |
| import android.text.TextUtils; |
| |
| /** |
| * Used to change the background of lines where the span is attached to. |
| */ |
| public interface LineBackgroundSpan extends ParagraphStyle |
| { |
| /** |
| * Draw the background on the canvas. |
| * |
| * @param canvas canvas on which the span should be rendered |
| * @param paint paint used to draw text, which should be left unchanged on exit |
| * @param left left position of the line relative to input canvas, in pixels |
| * @param right right position of the line relative to input canvas, in pixels |
| * @param top top position of the line relative to input canvas, in pixels |
| * @param baseline baseline of the text relative to input canvas, in pixels |
| * @param bottom bottom position of the line relative to input canvas, in pixels |
| * @param text current text |
| * @param start start character index of the line |
| * @param end end character index of the line |
| * @param lineNumber line number in the current text layout |
| */ |
| void drawBackground(@NonNull Canvas canvas, @NonNull Paint paint, |
| @Px int left, @Px int right, |
| @Px int top, @Px int baseline, @Px int bottom, |
| @NonNull CharSequence text, int start, int end, |
| int lineNumber); |
| /** |
| * Default implementation of the {@link LineBackgroundSpan}, which changes the background |
| * color of the lines to which the span is attached. |
| * <p> |
| * For example, an <code>LineBackgroundSpan</code> can be used like this: |
| * <pre> |
| * String text = "This is a multiline text. LineBackgroundSpan is applied here. This is a multiline text."; |
| * SpannableString string = new SpannableString(text); |
| * string.setSpan(new LineBackgroundSpan.Standard(Color.YELLOW), 26, 61, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE); |
| * </pre> |
| * <img src="{@docRoot}reference/android/images/text/style/linebackgroundspan.png" /> |
| * <figcaption>Text with <code>LineBackgroundSpan</code></figcaption> |
| */ |
| class Standard implements LineBackgroundSpan, ParcelableSpan { |
| |
| private final int mColor; |
| |
| /** |
| * Constructor taking a color integer. |
| * |
| * @param color Color integer that defines the background color. |
| */ |
| public Standard(@ColorInt int color) { |
| mColor = color; |
| } |
| |
| /** |
| * Creates a {@link LineBackgroundSpan.Standard} from a parcel |
| */ |
| public Standard(@NonNull Parcel src) { |
| mColor = src.readInt(); |
| } |
| |
| @Override |
| public int getSpanTypeId() { |
| return getSpanTypeIdInternal(); |
| } |
| |
| /** @hide */ |
| @Override |
| public int getSpanTypeIdInternal() { |
| return TextUtils.LINE_BACKGROUND_SPAN; |
| } |
| |
| @Override |
| public int describeContents() { |
| return 0; |
| } |
| |
| @Override |
| public void writeToParcel(@NonNull Parcel dest, int flags) { |
| writeToParcelInternal(dest, flags); |
| } |
| |
| /** @hide */ |
| @Override |
| public void writeToParcelInternal(@NonNull Parcel dest, int flags) { |
| dest.writeInt(mColor); |
| } |
| |
| /** |
| * @return the color of this span. |
| * @see Standard#Standard(int) |
| */ |
| @ColorInt |
| public final int getColor() { |
| return mColor; |
| } |
| |
| @Override |
| public void drawBackground(@NonNull Canvas canvas, @NonNull Paint paint, |
| @Px int left, @Px int right, |
| @Px int top, @Px int baseline, @Px int bottom, |
| @NonNull CharSequence text, int start, int end, |
| int lineNumber) { |
| final int originColor = paint.getColor(); |
| paint.setColor(mColor); |
| canvas.drawRect(left, top, right, bottom, paint); |
| paint.setColor(originColor); |
| } |
| } |
| } |