Move SlidingTabLayout and SlidingTabStrip into appropriate subpackage

4 files changed, 531 insertions, 2 deletions

diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/HelpActivity.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/HelpActivity.java
index 9edaff19a..bbc1e4b1f 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/HelpActivity.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/HelpActivity.java
@@ -25,7 +25,7 @@ import android.support.v7.app.ActionBarActivity;
 
 import org.sufficientlysecure.keychain.R;
 import org.sufficientlysecure.keychain.ui.adapter.PagerTabStripAdapter;
-import org.sufficientlysecure.keychain.util.SlidingTabLayout;
+import org.sufficientlysecure.keychain.ui.widget.SlidingTabLayout;
 
 public class HelpActivity extends ActionBarActivity {
     public static final String EXTRA_SELECTED_TAB = "selected_tab";
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/ViewKeyActivity.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/ViewKeyActivity.java
index b396cd849..7a0e83d9b 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/ViewKeyActivity.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/ViewKeyActivity.java
@@ -54,7 +54,7 @@ import org.sufficientlysecure.keychain.provider.KeychainContract;
 import org.sufficientlysecure.keychain.provider.ProviderHelper;
 import org.sufficientlysecure.keychain.ui.adapter.PagerTabStripAdapter;
 import org.sufficientlysecure.keychain.util.Log;
-import org.sufficientlysecure.keychain.util.SlidingTabLayout;
+import org.sufficientlysecure.keychain.ui.widget.SlidingTabLayout;
 
 import java.util.Date;
 import java.util.HashMap;
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/widget/SlidingTabLayout.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/widget/SlidingTabLayout.java
new file mode 100644
index 000000000..17471c86c
--- /dev/null
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/widget/SlidingTabLayout.java
@@ -0,0 +1,318 @@
+/*
+ * Copyright (C) 2013 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 org.sufficientlysecure.keychain.ui.widget;
+
+import android.content.Context;
+import android.graphics.Typeface;
+import android.os.Build;
+import android.support.v4.view.PagerAdapter;
+import android.support.v4.view.ViewPager;
+import android.util.AttributeSet;
+import android.util.TypedValue;
+import android.view.Gravity;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.widget.HorizontalScrollView;
+import android.widget.TextView;
+
+/**
+ * Copied from http://developer.android.com/samples/SlidingTabsColors/index.html
+ */
+
+/**
+ * To be used with ViewPager to provide a tab indicator component which give constant feedback as to
+ * the user's scroll progress.
+ * <p/>
+ * To use the component, simply add it to your view hierarchy. Then in your
+ * {@link android.app.Activity} or {@link android.support.v4.app.Fragment} call
+ * {@link #setViewPager(ViewPager)} providing it the ViewPager this layout is being used for.
+ * <p/>
+ * The colors can be customized in two ways. The first and simplest is to provide an array of colors
+ * via {@link #setSelectedIndicatorColors(int...)} and {@link #setDividerColors(int...)}. The
+ * alternative is via the {@link TabColorizer} interface which provides you complete control over
+ * which color is used for any individual position.
+ * <p/>
+ * The views used as tabs can be customized by calling {@link #setCustomTabView(int, int)},
+ * providing the layout ID of your custom layout.
+ */
+public class SlidingTabLayout extends HorizontalScrollView {
+
+    /**
+     * Allows complete control over the colors drawn in the tab layout. Set with
+     * {@link #setCustomTabColorizer(TabColorizer)}.
+     */
+    public interface TabColorizer {
+
+        /**
+         * @return return the color of the indicator used when {@code position} is selected.
+         */
+        int getIndicatorColor(int position);
+
+        /**
+         * @return return the color of the divider drawn to the right of {@code position}.
+         */
+        int getDividerColor(int position);
+
+    }
+
+    private static final int TITLE_OFFSET_DIPS = 24;
+    private static final int TAB_VIEW_PADDING_DIPS = 16;
+    private static final int TAB_VIEW_TEXT_SIZE_SP = 12;
+
+    private int mTitleOffset;
+
+    private int mTabViewLayoutId;
+    private int mTabViewTextViewId;
+
+    private ViewPager mViewPager;
+    private ViewPager.OnPageChangeListener mViewPagerPageChangeListener;
+
+    private final SlidingTabStrip mTabStrip;
+
+    public SlidingTabLayout(Context context) {
+        this(context, null);
+    }
+
+    public SlidingTabLayout(Context context, AttributeSet attrs) {
+        this(context, attrs, 0);
+    }
+
+    public SlidingTabLayout(Context context, AttributeSet attrs, int defStyle) {
+        super(context, attrs, defStyle);
+
+        // Disable the Scroll Bar
+        setHorizontalScrollBarEnabled(false);
+        // Make sure that the Tab Strips fills this View
+        setFillViewport(true);
+
+        mTitleOffset = (int) (TITLE_OFFSET_DIPS * getResources().getDisplayMetrics().density);
+
+        mTabStrip = new SlidingTabStrip(context);
+        addView(mTabStrip, LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
+    }
+
+    /**
+     * Set the custom {@link TabColorizer} to be used.
+     * <p/>
+     * If you only require simple custmisation then you can use
+     * {@link #setSelectedIndicatorColors(int...)} and {@link #setDividerColors(int...)} to achieve
+     * similar effects.
+     */
+    public void setCustomTabColorizer(TabColorizer tabColorizer) {
+        mTabStrip.setCustomTabColorizer(tabColorizer);
+    }
+
+    /**
+     * Sets the colors to be used for indicating the selected tab. These colors are treated as a
+     * circular array. Providing one color will mean that all tabs are indicated with the same color.
+     */
+    public void setSelectedIndicatorColors(int... colors) {
+        mTabStrip.setSelectedIndicatorColors(colors);
+    }
+
+    /**
+     * Sets the colors to be used for tab dividers. These colors are treated as a circular array.
+     * Providing one color will mean that all tabs are indicated with the same color.
+     */
+    public void setDividerColors(int... colors) {
+        mTabStrip.setDividerColors(colors);
+    }
+
+    /**
+     * Set the {@link ViewPager.OnPageChangeListener}. When using {@link SlidingTabLayout} you are
+     * required to set any {@link ViewPager.OnPageChangeListener} through this method. This is so
+     * that the layout can update it's scroll position correctly.
+     *
+     * @see ViewPager#setOnPageChangeListener(ViewPager.OnPageChangeListener)
+     */
+    public void setOnPageChangeListener(ViewPager.OnPageChangeListener listener) {
+        mViewPagerPageChangeListener = listener;
+    }
+
+    /**
+     * Set the custom layout to be inflated for the tab views.
+     *
+     * @param layoutResId Layout id to be inflated
+     * @param textViewId  id of the {@link TextView} in the inflated view
+     */
+    public void setCustomTabView(int layoutResId, int textViewId) {
+        mTabViewLayoutId = layoutResId;
+        mTabViewTextViewId = textViewId;
+    }
+
+    /**
+     * Sets the associated view pager. Note that the assumption here is that the pager content
+     * (number of tabs and tab titles) does not change after this call has been made.
+     */
+    public void setViewPager(ViewPager viewPager) {
+        mTabStrip.removeAllViews();
+
+        mViewPager = viewPager;
+        if (viewPager != null) {
+            viewPager.setOnPageChangeListener(new InternalViewPagerListener());
+            populateTabStrip();
+        }
+    }
+
+    /**
+     * Create a default view to be used for tabs. This is called if a custom tab view is not set via
+     * {@link #setCustomTabView(int, int)}.
+     */
+    protected TextView createDefaultTabView(Context context) {
+        TextView textView = new TextView(context);
+        textView.setGravity(Gravity.CENTER);
+        textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, TAB_VIEW_TEXT_SIZE_SP);
+        textView.setTypeface(Typeface.DEFAULT_BOLD);
+
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
+            // If we're running on Honeycomb or newer, then we can use the Theme's
+            // selectableItemBackground to ensure that the View has a pressed state
+            TypedValue outValue = new TypedValue();
+            getContext().getTheme().resolveAttribute(android.R.attr.selectableItemBackground,
+                    outValue, true);
+            textView.setBackgroundResource(outValue.resourceId);
+        }
+
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
+            // If we're running on ICS or newer, enable all-caps to match the Action Bar tab style
+            textView.setAllCaps(true);
+        }
+
+        int padding = (int) (TAB_VIEW_PADDING_DIPS * getResources().getDisplayMetrics().density);
+        textView.setPadding(padding, padding, padding, padding);
+
+        return textView;
+    }
+
+    private void populateTabStrip() {
+        final PagerAdapter adapter = mViewPager.getAdapter();
+        final View.OnClickListener tabClickListener = new TabClickListener();
+
+        for (int i = 0; i < adapter.getCount(); i++) {
+            View tabView = null;
+            TextView tabTitleView = null;
+
+            if (mTabViewLayoutId != 0) {
+                // If there is a custom tab view layout id set, try and inflate it
+                tabView = LayoutInflater.from(getContext()).inflate(mTabViewLayoutId, mTabStrip,
+                        false);
+                tabTitleView = (TextView) tabView.findViewById(mTabViewTextViewId);
+            }
+
+            if (tabView == null) {
+                tabView = createDefaultTabView(getContext());
+            }
+
+            if (tabTitleView == null && TextView.class.isInstance(tabView)) {
+                tabTitleView = (TextView) tabView;
+            }
+
+            tabTitleView.setText(adapter.getPageTitle(i));
+            tabView.setOnClickListener(tabClickListener);
+
+            mTabStrip.addView(tabView);
+        }
+    }
+
+    @Override
+    protected void onAttachedToWindow() {
+        super.onAttachedToWindow();
+
+        if (mViewPager != null) {
+            scrollToTab(mViewPager.getCurrentItem(), 0);
+        }
+    }
+
+    private void scrollToTab(int tabIndex, int positionOffset) {
+        final int tabStripChildCount = mTabStrip.getChildCount();
+        if (tabStripChildCount == 0 || tabIndex < 0 || tabIndex >= tabStripChildCount) {
+            return;
+        }
+
+        View selectedChild = mTabStrip.getChildAt(tabIndex);
+        if (selectedChild != null) {
+            int targetScrollX = selectedChild.getLeft() + positionOffset;
+
+            if (tabIndex > 0 || positionOffset > 0) {
+                // If we're not at the first child and are mid-scroll, make sure we obey the offset
+                targetScrollX -= mTitleOffset;
+            }
+
+            scrollTo(targetScrollX, 0);
+        }
+    }
+
+    private class InternalViewPagerListener implements ViewPager.OnPageChangeListener {
+        private int mScrollState;
+
+        @Override
+        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
+            int tabStripChildCount = mTabStrip.getChildCount();
+            if ((tabStripChildCount == 0) || (position < 0) || (position >= tabStripChildCount)) {
+                return;
+            }
+
+            mTabStrip.onViewPagerPageChanged(position, positionOffset);
+
+            View selectedTitle = mTabStrip.getChildAt(position);
+            int extraOffset = (selectedTitle != null)
+                    ? (int) (positionOffset * selectedTitle.getWidth())
+                    : 0;
+            scrollToTab(position, extraOffset);
+
+            if (mViewPagerPageChangeListener != null) {
+                mViewPagerPageChangeListener.onPageScrolled(position, positionOffset,
+                        positionOffsetPixels);
+            }
+        }
+
+        @Override
+        public void onPageScrollStateChanged(int state) {
+            mScrollState = state;
+
+            if (mViewPagerPageChangeListener != null) {
+                mViewPagerPageChangeListener.onPageScrollStateChanged(state);
+            }
+        }
+
+        @Override
+        public void onPageSelected(int position) {
+            if (mScrollState == ViewPager.SCROLL_STATE_IDLE) {
+                mTabStrip.onViewPagerPageChanged(position, 0f);
+                scrollToTab(position, 0);
+            }
+
+            if (mViewPagerPageChangeListener != null) {
+                mViewPagerPageChangeListener.onPageSelected(position);
+            }
+        }
+
+    }
+
+    private class TabClickListener implements View.OnClickListener {
+        @Override
+        public void onClick(View v) {
+            for (int i = 0; i < mTabStrip.getChildCount(); i++) {
+                if (v == mTabStrip.getChildAt(i)) {
+                    mViewPager.setCurrentItem(i);
+                    return;
+                }
+            }
+        }
+    }
+
+}
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/widget/SlidingTabStrip.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/widget/SlidingTabStrip.java
new file mode 100644
index 000000000..4c41e12c5
--- /dev/null
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/widget/SlidingTabStrip.java
@@ -0,0 +1,211 @@
+/*
+ * Copyright (C) 2013 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 org.sufficientlysecure.keychain.ui.widget;
+
+import android.R;
+import android.content.Context;
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.Paint;
+import android.util.AttributeSet;
+import android.util.TypedValue;
+import android.view.View;
+import android.widget.LinearLayout;
+
+/**
+ * Copied from http://developer.android.com/samples/SlidingTabsColors/index.html
+ */
+class SlidingTabStrip extends LinearLayout {
+
+    private static final int DEFAULT_BOTTOM_BORDER_THICKNESS_DIPS = 2;
+    private static final byte DEFAULT_BOTTOM_BORDER_COLOR_ALPHA = 0x26;
+    private static final int SELECTED_INDICATOR_THICKNESS_DIPS = 8;
+    private static final int DEFAULT_SELECTED_INDICATOR_COLOR = 0xFFAA66CC;
+
+    private static final int DEFAULT_DIVIDER_THICKNESS_DIPS = 1;
+    private static final byte DEFAULT_DIVIDER_COLOR_ALPHA = 0x20;
+    private static final float DEFAULT_DIVIDER_HEIGHT = 0.5f;
+
+    private final int mBottomBorderThickness;
+    private final Paint mBottomBorderPaint;
+
+    private final int mSelectedIndicatorThickness;
+    private final Paint mSelectedIndicatorPaint;
+
+    private final int mDefaultBottomBorderColor;
+
+    private final Paint mDividerPaint;
+    private final float mDividerHeight;
+
+    private int mSelectedPosition;
+    private float mSelectionOffset;
+
+    private SlidingTabLayout.TabColorizer mCustomTabColorizer;
+    private final SimpleTabColorizer mDefaultTabColorizer;
+
+    SlidingTabStrip(Context context) {
+        this(context, null);
+    }
+
+    SlidingTabStrip(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        setWillNotDraw(false);
+
+        final float density = getResources().getDisplayMetrics().density;
+
+        TypedValue outValue = new TypedValue();
+        context.getTheme().resolveAttribute(R.attr.colorForeground, outValue, true);
+        final int themeForegroundColor = outValue.data;
+
+        mDefaultBottomBorderColor = setColorAlpha(themeForegroundColor,
+                DEFAULT_BOTTOM_BORDER_COLOR_ALPHA);
+
+        mDefaultTabColorizer = new SimpleTabColorizer();
+        mDefaultTabColorizer.setIndicatorColors(DEFAULT_SELECTED_INDICATOR_COLOR);
+        mDefaultTabColorizer.setDividerColors(setColorAlpha(themeForegroundColor,
+                DEFAULT_DIVIDER_COLOR_ALPHA));
+
+        mBottomBorderThickness = (int) (DEFAULT_BOTTOM_BORDER_THICKNESS_DIPS * density);
+        mBottomBorderPaint = new Paint();
+        mBottomBorderPaint.setColor(mDefaultBottomBorderColor);
+
+        mSelectedIndicatorThickness = (int) (SELECTED_INDICATOR_THICKNESS_DIPS * density);
+        mSelectedIndicatorPaint = new Paint();
+
+        mDividerHeight = DEFAULT_DIVIDER_HEIGHT;
+        mDividerPaint = new Paint();
+        mDividerPaint.setStrokeWidth((int) (DEFAULT_DIVIDER_THICKNESS_DIPS * density));
+    }
+
+    void setCustomTabColorizer(SlidingTabLayout.TabColorizer customTabColorizer) {
+        mCustomTabColorizer = customTabColorizer;
+        invalidate();
+    }
+
+    void setSelectedIndicatorColors(int... colors) {
+        // Make sure that the custom colorizer is removed
+        mCustomTabColorizer = null;
+        mDefaultTabColorizer.setIndicatorColors(colors);
+        invalidate();
+    }
+
+    void setDividerColors(int... colors) {
+        // Make sure that the custom colorizer is removed
+        mCustomTabColorizer = null;
+        mDefaultTabColorizer.setDividerColors(colors);
+        invalidate();
+    }
+
+    void onViewPagerPageChanged(int position, float positionOffset) {
+        mSelectedPosition = position;
+        mSelectionOffset = positionOffset;
+        invalidate();
+    }
+
+    @Override
+    protected void onDraw(Canvas canvas) {
+        final int height = getHeight();
+        final int childCount = getChildCount();
+        final int dividerHeightPx = (int) (Math.min(Math.max(0f, mDividerHeight), 1f) * height);
+        final SlidingTabLayout.TabColorizer tabColorizer = mCustomTabColorizer != null
+                ? mCustomTabColorizer
+                : mDefaultTabColorizer;
+
+        // Thick colored underline below the current selection
+        if (childCount > 0) {
+            View selectedTitle = getChildAt(mSelectedPosition);
+            int left = selectedTitle.getLeft();
+            int right = selectedTitle.getRight();
+            int color = tabColorizer.getIndicatorColor(mSelectedPosition);
+
+            if (mSelectionOffset > 0f && mSelectedPosition < (getChildCount() - 1)) {
+                int nextColor = tabColorizer.getIndicatorColor(mSelectedPosition + 1);
+                if (color != nextColor) {
+                    color = blendColors(nextColor, color, mSelectionOffset);
+                }
+
+                // Draw the selection partway between the tabs
+                View nextTitle = getChildAt(mSelectedPosition + 1);
+                left = (int) (mSelectionOffset * nextTitle.getLeft() +
+                        (1.0f - mSelectionOffset) * left);
+                right = (int) (mSelectionOffset * nextTitle.getRight() +
+                        (1.0f - mSelectionOffset) * right);
+            }
+
+            mSelectedIndicatorPaint.setColor(color);
+
+            canvas.drawRect(left, height - mSelectedIndicatorThickness, right,
+                    height, mSelectedIndicatorPaint);
+        }
+
+        // Thin underline along the entire bottom edge
+        canvas.drawRect(0, height - mBottomBorderThickness, getWidth(), height, mBottomBorderPaint);
+
+        // Vertical separators between the titles
+        int separatorTop = (height - dividerHeightPx) / 2;
+        for (int i = 0; i < childCount - 1; i++) {
+            View child = getChildAt(i);
+            mDividerPaint.setColor(tabColorizer.getDividerColor(i));
+            canvas.drawLine(child.getRight(), separatorTop, child.getRight(),
+                    separatorTop + dividerHeightPx, mDividerPaint);
+        }
+    }
+
+    /**
+     * Set the alpha value of the {@code color} to be the given {@code alpha} value.
+     */
+    private static int setColorAlpha(int color, byte alpha) {
+        return Color.argb(alpha, Color.red(color), Color.green(color), Color.blue(color));
+    }
+
+    /**
+     * Blend {@code color1} and {@code color2} using the given ratio.
+     *
+     * @param ratio of which to blend. 1.0 will return {@code color1}, 0.5 will give an even blend,
+     *              0.0 will return {@code color2}.
+     */
+    private static int blendColors(int color1, int color2, float ratio) {
+        final float inverseRation = 1f - ratio;
+        float r = (Color.red(color1) * ratio) + (Color.red(color2) * inverseRation);
+        float g = (Color.green(color1) * ratio) + (Color.green(color2) * inverseRation);
+        float b = (Color.blue(color1) * ratio) + (Color.blue(color2) * inverseRation);
+        return Color.rgb((int) r, (int) g, (int) b);
+    }
+
+    private static class SimpleTabColorizer implements SlidingTabLayout.TabColorizer {
+        private int[] mIndicatorColors;
+        private int[] mDividerColors;
+
+        @Override
+        public final int getIndicatorColor(int position) {
+            return mIndicatorColors[position % mIndicatorColors.length];
+        }
+
+        @Override
+        public final int getDividerColor(int position) {
+            return mDividerColors[position % mDividerColors.length];
+        }
+
+        void setIndicatorColors(int... colors) {
+            mIndicatorColors = colors;
+        }
+
+        void setDividerColors(int... colors) {
+            mDividerColors = colors;
+        }
+    }
+}
\ No newline at end of file