diff options
Diffstat (limited to 'src/com/android/launcher3/BaseRecyclerViewFastScrollPopup.java')
-rw-r--r-- | src/com/android/launcher3/BaseRecyclerViewFastScrollPopup.java | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/src/com/android/launcher3/BaseRecyclerViewFastScrollPopup.java b/src/com/android/launcher3/BaseRecyclerViewFastScrollPopup.java new file mode 100644 index 000000000..aeeb5156d --- /dev/null +++ b/src/com/android/launcher3/BaseRecyclerViewFastScrollPopup.java @@ -0,0 +1,160 @@ +/* + * Copyright (C) 2015 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 com.android.launcher3; + +import android.animation.Animator; +import android.animation.ObjectAnimator; +import android.content.res.Resources; +import android.graphics.Canvas; +import android.graphics.Color; +import android.graphics.Paint; +import android.graphics.Rect; +import android.graphics.drawable.Drawable; + +/** + * The fast scroller popup that shows the section name the list will jump to. + */ +public class BaseRecyclerViewFastScrollPopup { + + private static final float FAST_SCROLL_OVERLAY_Y_OFFSET_FACTOR = 1.5f; + + private Resources mRes; + private BaseRecyclerView mRv; + + private Drawable mBg; + // The absolute bounds of the fast scroller bg + private Rect mBgBounds = new Rect(); + private int mBgOriginalSize; + private Rect mInvalidateRect = new Rect(); + private Rect mTmpRect = new Rect(); + + private String mSectionName; + private Paint mTextPaint; + private Rect mTextBounds = new Rect(); + private float mAlpha; + + private Animator mAlphaAnimator; + private boolean mVisible; + + public BaseRecyclerViewFastScrollPopup(BaseRecyclerView rv, Resources res) { + mRes = res; + mRv = rv; + mBgOriginalSize = res.getDimensionPixelSize(R.dimen.container_fastscroll_popup_size); + mBg = res.getDrawable(R.drawable.container_fastscroll_popup_bg); + mBg.setBounds(0, 0, mBgOriginalSize, mBgOriginalSize); + mTextPaint = new Paint(); + mTextPaint.setColor(Color.WHITE); + mTextPaint.setAntiAlias(true); + mTextPaint.setTextSize(res.getDimensionPixelSize(R.dimen.container_fastscroll_popup_text_size)); + } + + /** + * Sets the section name. + */ + public void setSectionName(String sectionName) { + if (!sectionName.equals(mSectionName)) { + mSectionName = sectionName; + mTextPaint.getTextBounds(sectionName, 0, sectionName.length(), mTextBounds); + // Update the width to use measureText since that is more accurate + mTextBounds.right = (int) (mTextBounds.left + mTextPaint.measureText(sectionName)); + } + } + + /** + * Updates the bounds for the fast scroller. + * @return the invalidation rect for this update. + */ + public Rect updateFastScrollerBounds(BaseRecyclerView rv, int lastTouchY) { + mInvalidateRect.set(mBgBounds); + + if (isVisible()) { + // Calculate the dimensions and position of the fast scroller popup + int edgePadding = rv.getMaxScrollbarWidth(); + int bgPadding = (mBgOriginalSize - mTextBounds.height()) / 2; + int bgHeight = mBgOriginalSize; + int bgWidth = Math.max(mBgOriginalSize, mTextBounds.width() + (2 * bgPadding)); + if (Utilities.isRtl(mRes)) { + mBgBounds.left = rv.getBackgroundPadding().left + (2 * rv.getMaxScrollbarWidth()); + mBgBounds.right = mBgBounds.left + bgWidth; + } else { + mBgBounds.right = rv.getWidth() - rv.getBackgroundPadding().right - + (2 * rv.getMaxScrollbarWidth()); + mBgBounds.left = mBgBounds.right - bgWidth; + } + mBgBounds.top = lastTouchY - (int) (FAST_SCROLL_OVERLAY_Y_OFFSET_FACTOR * bgHeight); + mBgBounds.top = Math.max(edgePadding, + Math.min(mBgBounds.top, rv.getHeight() - edgePadding - bgHeight)); + mBgBounds.bottom = mBgBounds.top + bgHeight; + } else { + mBgBounds.setEmpty(); + } + + // Combine the old and new fast scroller bounds to create the full invalidate rect + mInvalidateRect.union(mBgBounds); + return mInvalidateRect; + } + + /** + * Animates the visibility of the fast scroller popup. + */ + public void animateVisibility(boolean visible) { + if (mVisible != visible) { + mVisible = visible; + if (mAlphaAnimator != null) { + mAlphaAnimator.cancel(); + } + mAlphaAnimator = ObjectAnimator.ofFloat(this, "alpha", visible ? 1f : 0f); + mAlphaAnimator.setDuration(visible ? 200 : 150); + mAlphaAnimator.start(); + } + } + + // Setter/getter for the popup alpha for animations + public void setAlpha(float alpha) { + mAlpha = alpha; + mRv.invalidate(mBgBounds); + } + + public float getAlpha() { + return mAlpha; + } + + public int getHeight() { + return mBgOriginalSize; + } + + public void draw(Canvas c) { + if (isVisible()) { + // Draw the fast scroller popup + int restoreCount = c.save(Canvas.MATRIX_SAVE_FLAG); + c.translate(mBgBounds.left, mBgBounds.top); + mTmpRect.set(mBgBounds); + mTmpRect.offsetTo(0, 0); + mBg.setBounds(mTmpRect); + mBg.setAlpha((int) (mAlpha * 255)); + mBg.draw(c); + mTextPaint.setAlpha((int) (mAlpha * 255)); + c.drawText(mSectionName, (mBgBounds.width() - mTextBounds.width()) / 2, + mBgBounds.height() - (mBgBounds.height() - mTextBounds.height()) / 2, + mTextPaint); + c.restoreToCount(restoreCount); + } + } + + public boolean isVisible() { + return (mAlpha > 0f) && (mSectionName != null); + } +} |