diff options
Diffstat (limited to 'OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/widget/SlidingTabStrip.java')
| -rw-r--r-- | OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/widget/SlidingTabStrip.java | 211 |
1 files changed, 211 insertions, 0 deletions
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; + } + } +}
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