package com.mounacheikhna.decorators;
/**
* Created by cheikhna on 09/04/2015.
*/
import android.content.Context;
import android.content.res.Resources;
import android.content.res.TypedArray;
import android.text.Layout;
import android.text.StaticLayout;
import android.text.TextPaint;
import android.util.DisplayMetrics;
import android.util.Log;
import android.util.TypedValue;
import android.widget.TextView;
import com.mounacheikhna.decor.AttrsDecorator;
/**
* A decorator for a TextView to resize it's text to be no larger than the width of the view.
* (An example of a complicated decorator )
*/
public class AutofitDecorator extends AttrsDecorator<TextView> {
private static final String TAG = "AutofitDecorator";
private static final boolean SPEW = false;
private TextView mTextView;
// Minimum size of the text in pixels
private static final int DEFAULT_MIN_TEXT_SIZE = 11; //sp
// How precise we want to be when reaching the target textWidth size
private static final float PRECISION = 0.5f;
// Attributes
private boolean mSizeToFit;
private int mMaxLines;
private float mMinTextSize;
private float mMaxTextSize;
private float mPrecision;
private TextPaint mPaint;
@Override
protected int[] styleable() {
return R.styleable.AutofitDecorator;
}
@Override
protected Class<TextView> clazz() {
return TextView.class;
}
@Override
protected void apply(TextView view, TypedArray typedArray) {
mTextView = view;
boolean isAutofit = typedArray.getBoolean(R.styleable.AutofitDecorator_decorAutofitText, false);
if(!isAutofit) return;
float scaledDensity = mTextView.getContext().getResources().getDisplayMetrics().scaledDensity;
boolean sizeToFit = true;
int minTextSize = (int) scaledDensity * DEFAULT_MIN_TEXT_SIZE;
float precision = PRECISION;
//TODO: deal with case when one of these values is absent
sizeToFit = typedArray.getBoolean(R.styleable.AutofitDecorator_decorSizeToFit, sizeToFit);
minTextSize = typedArray.getDimensionPixelSize(R.styleable.AutofitDecorator_decorMinTextSize, minTextSize);
precision = typedArray.getFloat(R.styleable.AutofitDecorator_decorPrecision, precision);
mPaint = new TextPaint();
setSizeToFit(sizeToFit);
setRawTextSize(mTextView.getTextSize());
setRawMinTextSize(minTextSize);
setPrecision(precision);
}
/**
* If true, the text will automatically be resized to fit its constraints; if false, it will act
* like a normal TextView.
*/
public void setSizeToFit(boolean sizeToFit) {
mSizeToFit = sizeToFit;
refitText();
}
private void setRawTextSize(float size) {
if (size != mMaxTextSize) {
mMaxTextSize = size;
refitText();
}
}
private void setRawMinTextSize(float minSize) {
if (minSize != mMinTextSize) {
mMinTextSize = minSize;
refitText();
}
}
/**
* Set the amount of precision used to calculate the correct text size to fit within it's
* bounds. Lower precision is more precise and takes more time.
*
* @param precision The amount of precision.
*/
public void setPrecision(float precision) {
if (precision != mPrecision) {
mPrecision = precision;
refitText();
}
}
/**
* @return the amount of precision used to calculate the correct text size to fit within it's
* bounds.
*/
public float getPrecision() {
return mPrecision;
}
/**
* Re size the font so the specified text fits in the text box assuming the text box is the
* specified width.
*/
private void refitText() {
if (!mSizeToFit) {
return;
}
if (mMaxLines <= 0) {
// Don't auto-size since there's no limit on lines.
return;
}
String text = mTextView.getText().toString();
int targetWidth = mTextView.getWidth() - mTextView.getPaddingLeft() - mTextView.getPaddingRight();
if (targetWidth > 0) {
Context context = mTextView.getContext();
Resources r = Resources.getSystem();
DisplayMetrics displayMetrics;
float size = mMaxTextSize;
float high = size;
float low = 0;
if (context != null) {
r = context.getResources();
}
displayMetrics = r.getDisplayMetrics();
mPaint.set(mTextView.getPaint());
mPaint.setTextSize(size);
if ((mMaxLines == 1 && mPaint.measureText(text) > targetWidth)
|| getLineCount(text, mPaint, size, targetWidth, displayMetrics) > mMaxLines) {
size = getTextSize(text, mPaint, targetWidth, mMaxLines, low, high, mPrecision,
displayMetrics);
}
if (size < mMinTextSize) {
size = mMinTextSize;
}
mTextView.setTextSize(TypedValue.COMPLEX_UNIT_PX, size);
}
}
/**
* Recursive binary search to find the best size for the text
*/
private static float getTextSize(String text, TextPaint paint,
float targetWidth, int maxLines,
float low, float high, float precision,
DisplayMetrics displayMetrics) {
float mid = (low + high) / 2.0f;
int lineCount = 1;
StaticLayout layout = null;
paint.setTextSize(TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_PX, mid,
displayMetrics));
if (maxLines != 1) {
layout = new StaticLayout(text, paint, (int) targetWidth, Layout.Alignment.ALIGN_NORMAL,
1.0f, 0.0f, true);
lineCount = layout.getLineCount();
}
if (SPEW) {
Log.d(TAG, "low=" + low + " high=" + high + " mid=" + mid +
" target=" + targetWidth + " maxLines=" + maxLines + " lineCount=" + lineCount);
}
if (lineCount > maxLines) {
return getTextSize(text, paint, targetWidth, maxLines, low, mid, precision,
displayMetrics);
} else if (lineCount < maxLines) {
return getTextSize(text, paint, targetWidth, maxLines, mid, high, precision,
displayMetrics);
} else {
float maxLineWidth = 0;
if (maxLines == 1) {
maxLineWidth = paint.measureText(text);
} else {
for (int i = 0; i < lineCount; i++) {
if (layout.getLineWidth(i) > maxLineWidth) {
maxLineWidth = layout.getLineWidth(i);
}
}
}
if ((high - low) < precision) {
return low;
} else if (maxLineWidth > targetWidth) {
return getTextSize(text, paint, targetWidth, maxLines, low, mid, precision,
displayMetrics);
} else if (maxLineWidth < targetWidth) {
return getTextSize(text, paint, targetWidth, maxLines, mid, high, precision,
displayMetrics);
} else {
return mid;
}
}
}
/**
* {@inheritDoc}
*/
//@Override //since we cant have override with it here -> issue when frmwrk calls setTextSize on this afterwards
//probably it wont work (is there a way to have a delegate for mTextView to pass to this when setTextSize is called on it)
public void setTextSize(int unit, float size) {
if (!mSizeToFit) {
mTextView.setTextSize(unit, size);
}
Context context = mTextView.getContext();
Resources r = Resources.getSystem();
if (context != null) {
r = context.getResources();
}
setRawTextSize(TypedValue.applyDimension(unit, size, r.getDisplayMetrics()));
}
private static int getLineCount(String text, TextPaint paint, float size, float width,
DisplayMetrics displayMetrics) {
paint.setTextSize(TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_PX, size,
displayMetrics));
StaticLayout layout = new StaticLayout(text, paint, (int) width,
Layout.Alignment.ALIGN_NORMAL, 1.0f, 0.0f, true);
return layout.getLineCount();
}
}
