michael@0: /* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: package org.mozilla.gecko.preferences;
michael@0: 
michael@0: import org.mozilla.gecko.R;
michael@0: 
michael@0: import android.app.AlertDialog;
michael@0: import android.content.Context;
michael@0: import android.content.res.Resources;
michael@0: import android.graphics.Color;
michael@0: import android.preference.DialogPreference;
michael@0: import android.util.AttributeSet;
michael@0: import android.util.Log;
michael@0: import android.util.TypedValue;
michael@0: import android.view.LayoutInflater;
michael@0: import android.view.View;
michael@0: import android.view.ViewGroup;
michael@0: import android.widget.Button;
michael@0: import android.widget.ScrollView;
michael@0: import android.widget.TextView;
michael@0: 
michael@0: import java.util.HashMap;
michael@0: 
michael@0: class FontSizePreference extends DialogPreference {
michael@0:     private static final String LOGTAG = "FontSizePreference";
michael@0:     private static final int TWIP_TO_PT_RATIO = 20; // 20 twip = 1 point.
michael@0:     private static final int PREVIEW_FONT_SIZE_UNIT = TypedValue.COMPLEX_UNIT_PT;
michael@0:     private static final int DEFAULT_FONT_INDEX = 2;
michael@0: 
michael@0:     private final Context mContext;
michael@0:     /** Container for mPreviewFontView to allow for scrollable padding at the top of the view. */
michael@0:     private ScrollView mScrollingContainer;
michael@0:     private TextView mPreviewFontView;
michael@0:     private Button mIncreaseFontButton;
michael@0:     private Button mDecreaseFontButton;
michael@0: 
michael@0:     private final String[] mFontTwipValues;
michael@0:     private final String[] mFontSizeNames; // Ex: "Small".
michael@0:     /** Index into the above arrays for the saved preference value (from Gecko). */
michael@0:     private int mSavedFontIndex = DEFAULT_FONT_INDEX;
michael@0:     /** Index into the above arrays for the currently displayed font size (the preview). */
michael@0:     private int mPreviewFontIndex = mSavedFontIndex;
michael@0:     private final HashMap<String, Integer> mFontTwipToIndexMap;
michael@0: 
michael@0:     public FontSizePreference(Context context, AttributeSet attrs) {
michael@0:         super(context, attrs);
michael@0:         mContext = context;
michael@0: 
michael@0:         final Resources res = mContext.getResources();
michael@0:         mFontTwipValues = res.getStringArray(R.array.pref_font_size_values);
michael@0:         mFontSizeNames = res.getStringArray(R.array.pref_font_size_entries);
michael@0:         mFontTwipToIndexMap = new HashMap<String, Integer>();
michael@0:         for (int i = 0; i < mFontTwipValues.length; ++i) {
michael@0:             mFontTwipToIndexMap.put(mFontTwipValues[i], i);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     protected void onPrepareDialogBuilder(AlertDialog.Builder builder) {
michael@0:         final LayoutInflater inflater =
michael@0:             (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
michael@0:         View dialogView = inflater.inflate(R.layout.font_size_preference, null);
michael@0:         initInternalViews(dialogView);
michael@0:         updatePreviewFontSize(mFontTwipValues[mPreviewFontIndex]);
michael@0: 
michael@0:         builder.setTitle(null);
michael@0:         builder.setView(dialogView);
michael@0:     }
michael@0: 
michael@0:     /** Saves relevant views to instance variables and initializes their settings. */
michael@0:     private void initInternalViews(View dialogView) {
michael@0:         mScrollingContainer = (ScrollView) dialogView.findViewById(R.id.scrolling_container);
michael@0:         // Background cannot be set in XML (see bug 783597 - TODO: Change this to XML when bug is fixed).
michael@0:         mScrollingContainer.setBackgroundColor(Color.WHITE);
michael@0:         mPreviewFontView = (TextView) dialogView.findViewById(R.id.preview);
michael@0: 
michael@0:         mDecreaseFontButton = (Button) dialogView.findViewById(R.id.decrease_preview_font_button);
michael@0:         mIncreaseFontButton = (Button) dialogView.findViewById(R.id.increase_preview_font_button);
michael@0:         setButtonState(mPreviewFontIndex);
michael@0:         mDecreaseFontButton.setOnClickListener(new View.OnClickListener() {
michael@0:             @Override
michael@0:             public void onClick(View v) {
michael@0:                 mPreviewFontIndex = Math.max(mPreviewFontIndex - 1, 0);
michael@0:                 updatePreviewFontSize(mFontTwipValues[mPreviewFontIndex]);
michael@0:                 mIncreaseFontButton.setEnabled(true);
michael@0:                 // If we reached the minimum index, disable the button.
michael@0:                 if (mPreviewFontIndex == 0) {
michael@0:                     mDecreaseFontButton.setEnabled(false);
michael@0:                 }
michael@0:             }
michael@0:         });
michael@0:         mIncreaseFontButton.setOnClickListener(new View.OnClickListener() {
michael@0:             @Override
michael@0:             public void onClick(View v) {
michael@0:                 mPreviewFontIndex = Math.min(mPreviewFontIndex + 1, mFontTwipValues.length - 1);
michael@0:                 updatePreviewFontSize(mFontTwipValues[mPreviewFontIndex]);
michael@0: 
michael@0:                 mDecreaseFontButton.setEnabled(true);
michael@0:                 // If we reached the maximum index, disable the button.
michael@0:                 if (mPreviewFontIndex == mFontTwipValues.length - 1) {
michael@0:                     mIncreaseFontButton.setEnabled(false);
michael@0:                 }
michael@0:             }
michael@0:         });
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     protected void onDialogClosed(boolean positiveResult) {
michael@0:         super.onDialogClosed(positiveResult);
michael@0:         if (!positiveResult) {
michael@0:             mPreviewFontIndex = mSavedFontIndex;
michael@0:             return;
michael@0:         }
michael@0:         mSavedFontIndex = mPreviewFontIndex;
michael@0:         final String twipVal = mFontTwipValues[mSavedFontIndex];
michael@0:         final OnPreferenceChangeListener prefChangeListener = getOnPreferenceChangeListener();
michael@0:         if (prefChangeListener == null) {
michael@0:             Log.e(LOGTAG, "PreferenceChangeListener is null. FontSizePreference will not be saved to Gecko.");
michael@0:             return;
michael@0:         }
michael@0:         prefChangeListener.onPreferenceChange(this, twipVal);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Finds the index of the given twip value and sets it as the saved preference value. Also the
michael@0:      * current preview text size to the given value. Does not update the mPreviewFontView text size.
michael@0:      */
michael@0:     protected void setSavedFontSize(String twip) {
michael@0:         final Integer index = mFontTwipToIndexMap.get(twip);
michael@0:         if (index != null) {
michael@0:             mSavedFontIndex = index;
michael@0:             mPreviewFontIndex = mSavedFontIndex;
michael@0:             return;
michael@0:         }
michael@0:         resetSavedFontSizeToDefault();
michael@0:         Log.e(LOGTAG, "setSavedFontSize: Given font size does not exist in twip values map. Reverted to default font size.");
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Updates the mPreviewFontView to the given text size, resets the container's scroll to the top
michael@0:      * left, and invalidates the view. Does not update the font indices.
michael@0:      */
michael@0:     private void updatePreviewFontSize(String twip) {
michael@0:         float pt = convertTwipStrToPT(twip);
michael@0:         // Android will not render a font size of 0 pt but for Gecko, 0 twip turns off font
michael@0:         // inflation. Thus we special case 0 twip to display a renderable font size.
michael@0:         if (pt == 0) {
michael@0:             // Android adds an inexplicable extra margin on the smallest font size so to get around
michael@0:             // this, we reinflate the view.
michael@0:             ViewGroup parentView = (ViewGroup) mScrollingContainer.getParent();
michael@0:             parentView.removeAllViews();
michael@0:             final LayoutInflater inflater =
michael@0:                 (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
michael@0:             View dialogView = inflater.inflate(R.layout.font_size_preference, parentView);
michael@0:             initInternalViews(dialogView);
michael@0:             mPreviewFontView.setTextSize(PREVIEW_FONT_SIZE_UNIT, 1);
michael@0:         } else {
michael@0:             mPreviewFontView.setTextSize(PREVIEW_FONT_SIZE_UNIT, pt);
michael@0:         }
michael@0:         mScrollingContainer.scrollTo(0, 0);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Resets the font indices to the default value. Does not update the mPreviewFontView text size.
michael@0:      */
michael@0:     private void resetSavedFontSizeToDefault() {
michael@0:         mSavedFontIndex = DEFAULT_FONT_INDEX;
michael@0:         mPreviewFontIndex = mSavedFontIndex;
michael@0:     }
michael@0: 
michael@0:     private void setButtonState(int index) {
michael@0:         if (index == 0) {
michael@0:             mDecreaseFontButton.setEnabled(false);
michael@0:         } else if (index == mFontTwipValues.length - 1) {
michael@0:             mIncreaseFontButton.setEnabled(false);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Returns the name of the font size (ex: "Small") at the currently saved preference value.
michael@0:      */
michael@0:     protected String getSavedFontSizeName() {
michael@0:         return mFontSizeNames[mSavedFontIndex];
michael@0:     }
michael@0: 
michael@0:     private float convertTwipStrToPT(String twip) {
michael@0:         return Float.parseFloat(twip) / TWIP_TO_PT_RATIO;
michael@0:     }
michael@0: }