src.android.text.style.LeadingMarginSpan Maven / Gradle / Ivy
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/*
* 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.graphics.Canvas;
import android.graphics.Paint;
import android.os.Parcel;
import android.text.Layout;
import android.text.ParcelableSpan;
import android.text.TextUtils;
/**
* A paragraph style affecting the leading margin. There can be multiple leading
* margin spans on a single paragraph; they will be rendered in order, each
* adding its margin to the ones before it. The leading margin is on the right
* for lines in a right-to-left paragraph.
*
* LeadingMarginSpans should be attached from the first character to the last
* character of a single paragraph.
*/
public interface LeadingMarginSpan
extends ParagraphStyle
{
/**
* Returns the amount by which to adjust the leading margin. Positive values
* move away from the leading edge of the paragraph, negative values move
* towards it.
*
* @param first true if the request is for the first line of a paragraph,
* false for subsequent lines
* @return the offset for the margin.
*/
public int getLeadingMargin(boolean first);
/**
* Renders the leading margin. This is called before the margin has been
* adjusted by the value returned by {@link #getLeadingMargin(boolean)}.
*
* @param c the canvas
* @param p the paint. The this should be left unchanged on exit.
* @param x the current position of the margin
* @param dir the base direction of the paragraph; if negative, the margin
* is to the right of the text, otherwise it is to the left.
* @param top the top of the line
* @param baseline the baseline of the line
* @param bottom the bottom of the line
* @param text the text
* @param start the start of the line
* @param end the end of the line
* @param first true if this is the first line of its paragraph
* @param layout the layout containing this line
*/
public void drawLeadingMargin(Canvas c, Paint p,
int x, int dir,
int top, int baseline, int bottom,
CharSequence text, int start, int end,
boolean first, Layout layout);
/**
* An extended version of {@link LeadingMarginSpan}, which allows the
* implementor to specify the number of lines of the paragraph to which
* this object is attached that the "first line of paragraph" margin width
* will be applied to.
*
* There should only be one LeadingMarginSpan2 per paragraph. The leading
* margin line count affects all LeadingMarginSpans in the paragraph,
* adjusting the number of lines to which the first line margin is applied.
*
* As with LeadingMarginSpans, LeadingMarginSpan2s should be attached from
* the beginning to the end of a paragraph.
*/
public interface LeadingMarginSpan2 extends LeadingMarginSpan, WrapTogetherSpan {
/**
* Returns the number of lines of the paragraph to which this object is
* attached that the "first line" margin will apply to.
*/
public int getLeadingMarginLineCount();
};
/**
* The standard implementation of LeadingMarginSpan, which adjusts the
* margin but does not do any rendering.
*/
public static class Standard implements LeadingMarginSpan, ParcelableSpan {
private final int mFirst, mRest;
/**
* Constructor taking separate indents for the first and subsequent
* lines.
*
* @param first the indent for the first line of the paragraph
* @param rest the indent for the remaining lines of the paragraph
*/
public Standard(int first, int rest) {
mFirst = first;
mRest = rest;
}
/**
* Constructor taking an indent for all lines.
* @param every the indent of each line
*/
public Standard(int every) {
this(every, every);
}
public Standard(Parcel src) {
mFirst = src.readInt();
mRest = src.readInt();
}
public int getSpanTypeId() {
return getSpanTypeIdInternal();
}
/** @hide */
public int getSpanTypeIdInternal() {
return TextUtils.LEADING_MARGIN_SPAN;
}
public int describeContents() {
return 0;
}
public void writeToParcel(Parcel dest, int flags) {
writeToParcelInternal(dest, flags);
}
/** @hide */
public void writeToParcelInternal(Parcel dest, int flags) {
dest.writeInt(mFirst);
dest.writeInt(mRest);
}
public int getLeadingMargin(boolean first) {
return first ? mFirst : mRest;
}
public void drawLeadingMargin(Canvas c, Paint p,
int x, int dir,
int top, int baseline, int bottom,
CharSequence text, int start, int end,
boolean first, Layout layout) {
;
}
}
}