package com.tylersuehr.esr;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Typeface;
import android.support.annotation.ColorInt;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.view.GravityCompat;
import android.support.v4.view.ViewCompat;
import android.text.Layout;
import android.text.StaticLayout;
import android.text.TextPaint;
import android.util.DisplayMetrics;
import android.view.Gravity;
/**
* Copyright © 2017 Tyler Suehr
*
* Subclass of {@link AbstractStateDisplay} that contains properties for two texts (one above
* the other one), a title and a subtitle perhaps, and affords an API to draw and manipulate
* them.
*
* @author Tyler Suehr
* @version 1.0
*/
public class TextStateDisplay extends AbstractStateDisplay {
private boolean textLayoutsConfigured = false;
/* Properties for the title text */
private final TextPaint titlePaint = new TextPaint(Paint.ANTI_ALIAS_FLAG);
private StaticLayout titleLayout;
private String title;
/* Properties for the subtitle text */
private final TextPaint subtitlePaint = new TextPaint(Paint.ANTI_ALIAS_FLAG);
private StaticLayout subtitleLayout;
private String subtitle;
/* Stores the gravity for the text */
private int textGravity = Gravity.CENTER;
/* Space between the title and subtitle texts */
private int titleSpacing;
public TextStateDisplay(Context c) {
this(c, "", "");
}
public TextStateDisplay(Context c, @NonNull String title, @Nullable String subtitle) {
DisplayMetrics dm = c.getResources().getDisplayMetrics();
// Setup default sizes
final int large = (int)(16f * dm.density);
setPadding(large, large, large, large);
this.titleSpacing = (int)(4f * dm.scaledDensity);
// Setup title defaults
this.titlePaint.setTextAlign(Paint.Align.CENTER);
this.titlePaint.setTextSize(18f * dm.scaledDensity);
this.titlePaint.setColor(Color.BLACK);
this.title = title;
// Default to a single line of text
this.titleLayout = new StaticLayout(title,
titlePaint,
(int)titlePaint.measureText(title),
Layout.Alignment.ALIGN_NORMAL,
1.0f, 0, false);
// Setup subtitle defaults
this.subtitlePaint.setTextSize(14f * dm.scaledDensity);
this.subtitlePaint.setTextAlign(Paint.Align.CENTER);
this.subtitlePaint.setColor(Color.GRAY);
this.subtitle = subtitle;
// Default to a single line of text
this.subtitleLayout = new StaticLayout(subtitle,
subtitlePaint,
(int)subtitlePaint.measureText(subtitle),
Layout.Alignment.ALIGN_NORMAL,
1.0f, 0, false);
}
@Override
public void onDrawState(EmptyStateRecyclerView rv, Canvas canvas) {
final int width = rv.getMeasuredWidth();
final int height = rv.getMeasuredHeight();
configureTextLayouts(width);
// Account for vertical text gravity
final int verticalGravity = textGravity&Gravity.VERTICAL_GRAVITY_MASK;
float dy;
switch (verticalGravity) {
case Gravity.CENTER_VERTICAL:
dy = (height >> 1) - ((int)getFullTextHeight() >> 1);
break;
case Gravity.BOTTOM:
dy = height - getFullTextHeight();
break;
default:
case Gravity.TOP:
dy = 0;
break;
}
dy += getPaddingTop();
final int horizontalGravity = Gravity.getAbsoluteGravity(textGravity,
ViewCompat.getLayoutDirection(rv))&Gravity.HORIZONTAL_GRAVITY_MASK;
// Draw the title text
canvas.save();
canvas.translate(
getDx(width, horizontalGravity, titlePaint, titleLayout),
dy);
this.titleLayout.draw(canvas);
canvas.restore();
// Add spacing for under the text with the title spacing
dy += titleLayout.getHeight() + titleSpacing;
// Draw the subtitle text under the title text
canvas.save();
canvas.translate(
getDx(width, horizontalGravity, subtitlePaint, subtitleLayout),
dy);
this.subtitleLayout.draw(canvas);
canvas.restore();
}
@Override
public void setPadding(int left, int top, int right, int bottom) {
super.setPadding(left, top, right, bottom);
invalidateText();
}
/**
* Sets the overall alignment for the text (supports all gravity variations
* except for RIGHT and END).
* @param gravity Text gravity
*/
public void setTextGravity(int gravity) {
// Let's adjust paint alignment to fit horizontal gravity (END not supported)
final int horizontalGravity = Gravity.getAbsoluteGravity(gravity,
ViewCompat.LAYOUT_DIRECTION_LTR)&Gravity.HORIZONTAL_GRAVITY_MASK;
switch (horizontalGravity) {
case GravityCompat.START:
this.titlePaint.setTextAlign(Paint.Align.LEFT);
this.subtitlePaint.setTextAlign(Paint.Align.LEFT);
break;
case Gravity.CENTER_HORIZONTAL:
this.titlePaint.setTextAlign(Paint.Align.CENTER);
this.subtitlePaint.setTextAlign(Paint.Align.CENTER);
break;
}
this.textGravity = gravity;
// No invalidation needed
}
/**
* Sets the spacing between the title and subtitle texts.
* @param spacing Spacing
*/
public void setTitleSpacing(int spacing) {
this.titleSpacing = spacing;
// No invalidation needed
}
/**
* Sets the text color of the title text.
* @param color Title text color
*/
public void setTitleTextColor(@ColorInt int color) {
this.titlePaint.setColor(color);
invalidateText();
}
/**
* Sets the text size of the title text.
* @param textSize Title text size
*/
public void setTitleTextSize(float textSize) {
this.titlePaint.setTextSize(textSize);
invalidateText();
}
/**
* Sets the paint alignment that draws the title.
* @param align {@link android.graphics.Paint.Align}
*/
public void setTitleTextAlign(Paint.Align align) {
this.titlePaint.setTextAlign(align);
invalidateText();
}
/**
* Sets the title text to be drawn.
* @param title Title
*/
public void setTitle(String title) {
this.title = title;
invalidateText();
}
/**
* Sets the text color of the subtitle text.
* @param color Subtitle text color
*/
public void setSubtitleTextColor(@ColorInt int color) {
this.subtitlePaint.setColor(color);
invalidateText();
}
/**
* Sets the text size of the subtitle text.
* @param textSize Subtitle text size
*/
public void setSubtitleTextSize(float textSize) {
this.subtitlePaint.setTextSize(textSize);
invalidateText();
}
/**
* Sets the paint alignment that draws the subtitle.
* @param align {@link android.graphics.Paint.Align}
*/
public void setSubtitleTextAlign(Paint.Align align) {
this.subtitlePaint.setTextAlign(align);
invalidateText();
}
/**
* Sets the subtitle to be drawn.
* @param subtitle Subtitle
*/
public void setSubtitle(String subtitle) {
this.subtitle = subtitle;
invalidateText();
}
/**
* Sets the typeface used to draw the title and subtitle texts.
* @param typeface {@link Typeface}
*/
public void setTypeface(Typeface typeface) {
this.titlePaint.setTypeface(typeface);
this.subtitlePaint.setTypeface(typeface);
invalidateText();
}
private void invalidateText() {
this.textLayoutsConfigured = false;
}
private float getFullTextHeight() {
return titleLayout.getHeight() // Height of all title lines (could be more than 1)
+ subtitleLayout.getHeight() // Height of all subtitle lines (could be more than 1)
+ titleSpacing + getPaddingTop() + getPaddingBottom(); // Spacing with top & bottom padding
}
private float getDx(final int width,
final int horizontalGravity,
final Paint paint,
final StaticLayout layout) {
final boolean centered = paint.getTextAlign() == Paint.Align.CENTER;
final float dx;
switch (horizontalGravity) { // No support for GravityCompat.END
case Gravity.CENTER_HORIZONTAL:
dx = (width >> 1) - (centered ? 0 : (layout.getWidth() >> 1) - getPaddingLeft());
break;
default:
case GravityCompat.START:
dx = getPaddingLeft();
break;
}
return dx;
}
private void configureTextLayouts(final int availableWidth) {
if (!textLayoutsConfigured) {
final int totalNeededPadding = getPaddingLeft() + getPaddingRight();
// Create new static layout only if needed!
if ((titleLayout.getWidth() + totalNeededPadding) > availableWidth) {
this.titleLayout = new StaticLayout(title,
titlePaint,
availableWidth - totalNeededPadding,
Layout.Alignment.ALIGN_NORMAL,
1.15f, 0, false);
}
// Create new static layout only if needed!
if ((subtitleLayout.getWidth() + totalNeededPadding) > availableWidth) {
this.subtitleLayout = new StaticLayout(subtitle,
subtitlePaint,
availableWidth - totalNeededPadding,
Layout.Alignment.ALIGN_NORMAL,
1.15f, 0, false);
}
textLayoutsConfigured = true;
}
}
}
