// Copyright 2022 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
package org.chromium.components.browser_ui.accessibility;
import static org.chromium.content_public.browser.HostZoomMap.AVAILABLE_ZOOM_FACTORS;
import android.content.Context;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.view.View;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.SeekBar;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.preference.Preference;
import androidx.preference.PreferenceViewHolder;
import org.chromium.components.browser_ui.accessibility.AccessibilitySettingsDelegate.IntegerPreferenceDelegate;
import org.chromium.content_public.browser.ContentFeatureList;
import org.chromium.content_public.browser.ContentFeatureMap;
import org.chromium.ui.widget.ChromeImageButton;
/** Custom preference for the page zoom section of Accessibility Settings. */
public class PageZoomPreference extends Preference implements SeekBar.OnSeekBarChangeListener {
private int mInitialValue;
private SeekBar mSeekBar;
private ChromeImageButton mDecreaseButton;
private ChromeImageButton mIncreaseButton;
private TextView mCurrentValueText;
private SeekBar mTextSizeContrastSeekBar;
private ChromeImageButton mTextSizeContrastDecreaseButton;
private ChromeImageButton mTextSizeContrastIncreaseButton;
private TextView mTextSizeContrastCurrentLevelText;
private IntegerPreferenceDelegate mTextSizeContrastDelegate;
private static final int TEXT_SIZE_CONTRAST_BUTTON_INCREMENT = 10;
// Values taken from dimens of text_size_* in //ui/android/java/res/values/dimens.xml
private static final float DEFAULT_LARGE_TEXT_SIZE_SP = 16.0f;
private static final float DEFAULT_MEDIUM_TEXT_SIZE_SP = 14.0f;
private static final float DEFAULT_SMALL_TEXT_SIZE_SP = 12.0f;
private float mDefaultPreviewImageSize;
private ImageView mPreviewImage;
private LinearLayout.LayoutParams mPreviewImageParams;
private TextView mPreviewLargeText;
private TextView mPreviewMediumText;
private TextView mPreviewSmallText;
private float mCurrentMultiplier;
private int mTextSizeContrastFactor;
public PageZoomPreference(@NonNull Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
setLayoutResource(R.layout.page_zoom_preference);
}
@Override
public void onBindViewHolder(@NonNull PreferenceViewHolder holder) {
super.onBindViewHolder(holder);
// Re-use the main control layout, but remove extra padding and background.
LinearLayout container = (LinearLayout) holder.findViewById(R.id.page_zoom_view_container);
int top = container.getPaddingTop();
int bot = container.getPaddingBottom();
container.setBackground(null);
container.setPadding(0, top, 0, bot);
mPreviewLargeText = (TextView) holder.findViewById(R.id.page_zoom_preview_large_text);
mPreviewMediumText = (TextView) holder.findViewById(R.id.page_zoom_preview_medium_text);
mPreviewSmallText = (TextView) holder.findViewById(R.id.page_zoom_preview_small_text);
var resources = getContext().getResources();
mDefaultPreviewImageSize =
resources.getDimensionPixelSize(R.dimen.page_zoom_preview_image_size);
mPreviewImage = (ImageView) holder.findViewById(R.id.page_zoom_preview_image);
mPreviewImageParams =
new LinearLayout.LayoutParams(mPreviewImage.getWidth(), mPreviewImage.getHeight());
// Set up Page Zoom slider.
mCurrentValueText = (TextView) holder.findViewById(R.id.page_zoom_current_value_text);
mCurrentValueText.setText(resources.getString(R.string.page_zoom_level, 100));
mDecreaseButton =
(ChromeImageButton) holder.findViewById(R.id.page_zoom_decrease_zoom_button);
mDecreaseButton.setOnClickListener(v -> onHandleDecreaseClicked());
mIncreaseButton =
(ChromeImageButton) holder.findViewById(R.id.page_zoom_increase_zoom_button);
mIncreaseButton.setOnClickListener(v -> onHandleIncreaseClicked());
mSeekBar = (SeekBar) holder.findViewById(R.id.page_zoom_slider);
mSeekBar.setOnSeekBarChangeListener(this);
mSeekBar.setMax(PageZoomUtils.PAGE_ZOOM_MAXIMUM_SEEKBAR_VALUE);
mSeekBar.setProgress(mInitialValue);
mCurrentMultiplier = mInitialValue;
updateViewsOnProgressChanged(mInitialValue, mSeekBar);
// Set up text size contrast slider.
if (ContentFeatureMap.isEnabled(ContentFeatureList.SMART_ZOOM)) {
holder.findViewById(R.id.text_size_contrast_title).setVisibility(View.VISIBLE);
holder.findViewById(R.id.text_size_contrast_summary).setVisibility(View.VISIBLE);
holder.findViewById(R.id.text_size_contrast_layout_container)
.setVisibility(View.VISIBLE);
mTextSizeContrastCurrentLevelText =
(TextView) holder.findViewById(R.id.text_size_contrast_current_value_text);
mTextSizeContrastCurrentLevelText.setText(
resources.getString(R.string.text_size_contrast_level, 0));
mTextSizeContrastCurrentLevelText.setVisibility(View.VISIBLE);
mTextSizeContrastDecreaseButton =
(ChromeImageButton)
holder.findViewById(R.id.text_size_contrast_decrease_zoom_button);
mTextSizeContrastDecreaseButton.setOnClickListener(
v -> onHandleContrastDecreaseClicked());
mTextSizeContrastDecreaseButton.setVisibility(View.VISIBLE);
mTextSizeContrastIncreaseButton =
(ChromeImageButton)
holder.findViewById(R.id.text_size_contrast_increase_zoom_button);
mTextSizeContrastIncreaseButton.setOnClickListener(
v -> onHandleContrastIncreaseClicked());
mTextSizeContrastIncreaseButton.setVisibility(View.VISIBLE);
mTextSizeContrastSeekBar =
(SeekBar) holder.findViewById(R.id.text_size_contrast_slider);
mTextSizeContrastSeekBar.setOnSeekBarChangeListener(this);
mTextSizeContrastSeekBar.setMax(PageZoomUtils.TEXT_SIZE_CONTRAST_MAX_LEVEL);
mTextSizeContrastFactor = mTextSizeContrastDelegate.getValue();
mTextSizeContrastSeekBar.setProgress(mTextSizeContrastFactor);
mTextSizeContrastSeekBar.setVisibility(View.VISIBLE);
updateViewsOnProgressChanged(mTextSizeContrastFactor, mTextSizeContrastSeekBar);
}
}
/**
* Initial values to set the progress of seekbars.
* @param zoomLevel int - existing user pref value for zoom level (or default).
*/
public void setInitialValue(int zoomLevel) {
mInitialValue = zoomLevel;
}
/**
* Set a delegate for the text size contrast slider functionality.
* @param delegate IntegerPreferenceDelegate - embedder's instance of a preference delegate.
*/
public void setTextSizeContrastDelegate(IntegerPreferenceDelegate delegate) {
mTextSizeContrastDelegate = delegate;
}
private void updateViewsOnProgressChanged(int progress, SeekBar seekBar) {
updateZoomPercentageText(progress, seekBar);
updatePreviewWidget(progress, seekBar);
updateButtonStates(progress, seekBar);
}
private void updateZoomPercentageText(int progress, SeekBar seekBar) {
if (seekBar.getId() == R.id.page_zoom_slider) {
int zoomLevel =
(int) Math.round(100 * PageZoomUtils.convertSeekBarValueToZoomLevel(progress));
mCurrentValueText.setText(
getContext().getResources().getString(R.string.page_zoom_level, zoomLevel));
} else if (seekBar.getId() == R.id.text_size_contrast_slider) {
mTextSizeContrastCurrentLevelText.setText(
getContext()
.getResources()
.getString(R.string.text_size_contrast_level, progress));
}
}
private void updatePreviewWidget(int progress, SeekBar seekBar) {
if (seekBar.getId() == R.id.page_zoom_slider) {
mCurrentMultiplier = (float) PageZoomUtils.convertSeekBarValueToZoomLevel(progress);
} else if (seekBar.getId() == R.id.text_size_contrast_slider) {
mTextSizeContrastFactor = progress;
}
mPreviewLargeText.setTextSize(
TypedValue.COMPLEX_UNIT_SP, calculateAdjustedTextSize(DEFAULT_LARGE_TEXT_SIZE_SP));
mPreviewMediumText.setTextSize(
TypedValue.COMPLEX_UNIT_SP, calculateAdjustedTextSize(DEFAULT_MEDIUM_TEXT_SIZE_SP));
mPreviewSmallText.setTextSize(
TypedValue.COMPLEX_UNIT_SP, calculateAdjustedTextSize(DEFAULT_SMALL_TEXT_SIZE_SP));
// TODO(crbug.com/40919531): Edit preview images when smart image sizing is added.
mPreviewImageParams.width = (int) (mDefaultPreviewImageSize * mCurrentMultiplier);
mPreviewImageParams.height = (int) (mDefaultPreviewImageSize * mCurrentMultiplier);
mPreviewImage.setLayoutParams(mPreviewImageParams);
}
private float calculateAdjustedTextSize(float startingTextSize) {
// TODO(crbug.com/40919531): Add the following non-linear formula
if (mTextSizeContrastFactor > 0
&& ContentFeatureMap.isEnabled(ContentFeatureList.SMART_ZOOM)) {}
return startingTextSize * mCurrentMultiplier;
}
private void updateButtonStates(int progress, SeekBar seekBar) {
if (seekBar.getId() == R.id.page_zoom_slider) {
double newZoomFactor = PageZoomUtils.convertSeekBarValueToZoomFactor(progress);
// If the new zoom factor is greater than the minimum zoom factor, enable decrease
// button.
mDecreaseButton.setEnabled(newZoomFactor > AVAILABLE_ZOOM_FACTORS[0]);
// If the new zoom factor is less than the maximum zoom factor, enable increase button.
mIncreaseButton.setEnabled(
newZoomFactor < AVAILABLE_ZOOM_FACTORS[AVAILABLE_ZOOM_FACTORS.length - 1]);
} else if (seekBar.getId() == R.id.text_size_contrast_slider) {
mTextSizeContrastDecreaseButton.setEnabled(progress > 0);
mTextSizeContrastIncreaseButton.setEnabled(
progress < PageZoomUtils.TEXT_SIZE_CONTRAST_MAX_LEVEL);
}
}
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
// Update the zoom percentage text, preview widget and enabled state of increase/decrease
// buttons as the slider is updated.
updateViewsOnProgressChanged(progress, seekBar);
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
if (seekBar.getId() == R.id.page_zoom_slider) {
// When a user stops changing the slider value, record the new value in prefs.
callChangeListener(seekBar.getProgress());
} else if (seekBar.getId() == R.id.text_size_contrast_slider) {
saveTextSizeContrastValueToPreferences();
}
}
private void onHandleDecreaseClicked() {
// When decreasing zoom, "snap" to the greatest preset value that is less than the current.
double currentZoomFactor =
PageZoomUtils.convertSeekBarValueToZoomFactor(mSeekBar.getProgress());
int index = PageZoomUtils.getNextIndex(true, currentZoomFactor);
if (index >= 0) {
int seekBarValue =
PageZoomUtils.convertZoomFactorToSeekBarValue(AVAILABLE_ZOOM_FACTORS[index]);
mSeekBar.setProgress(seekBarValue);
callChangeListener(seekBarValue);
}
}
private void onHandleIncreaseClicked() {
// When increasing zoom, "snap" to the smallest preset value that is more than the current.
double currentZoomFactor =
PageZoomUtils.convertSeekBarValueToZoomFactor(mSeekBar.getProgress());
int index = PageZoomUtils.getNextIndex(false, currentZoomFactor);
if (index <= AVAILABLE_ZOOM_FACTORS.length - 1) {
int seekBarValue =
PageZoomUtils.convertZoomFactorToSeekBarValue(AVAILABLE_ZOOM_FACTORS[index]);
mSeekBar.setProgress(seekBarValue);
callChangeListener(seekBarValue);
}
}
private void onHandleContrastDecreaseClicked() {
// Decrease the contrast slider by defined increment.
mTextSizeContrastSeekBar.setProgress(
mTextSizeContrastSeekBar.getProgress() - TEXT_SIZE_CONTRAST_BUTTON_INCREMENT);
saveTextSizeContrastValueToPreferences();
}
private void onHandleContrastIncreaseClicked() {
// Increase the contrast slider by defined increment.
mTextSizeContrastSeekBar.setProgress(
mTextSizeContrastSeekBar.getProgress() + TEXT_SIZE_CONTRAST_BUTTON_INCREMENT);
saveTextSizeContrastValueToPreferences();
}
private void saveTextSizeContrastValueToPreferences() {
mTextSizeContrastDelegate.setValue(mTextSizeContrastSeekBar.getProgress());
}
// Testing methods.
public SeekBar getZoomSliderForTesting() {
return mSeekBar;
}
public void setZoomValueForTesting(int progress) {
mSeekBar.setProgress(progress);
updateViewsOnProgressChanged(progress, mSeekBar);
}
public SeekBar getTextSizeContrastSliderForTesting() {
return mTextSizeContrastSeekBar;
}
public void setTextContrastValueForTesting(int contrast) {
mTextSizeContrastSeekBar.setProgress(contrast);
updateViewsOnProgressChanged(contrast, mTextSizeContrastSeekBar);
}
}
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