Merge "Refactoring WallpaperOffsetInterpolator to a new file Removing some us unused methods" into ub-launcher3-master

1 files changed, 225 insertions, 0 deletions

diff --git a/src/com/android/launcher3/util/WallpaperOffsetInterpolator.java b/src/com/android/launcher3/util/WallpaperOffsetInterpolator.java
new file mode 100644
index 000000000..1fbd0dc13
--- /dev/null
+++ b/src/com/android/launcher3/util/WallpaperOffsetInterpolator.java
@@ -0,0 +1,225 @@
+package com.android.launcher3.util;
+
+import android.app.WallpaperManager;
+import android.os.IBinder;
+import android.util.Log;
+import android.view.Choreographer;
+import android.view.animation.DecelerateInterpolator;
+import android.view.animation.Interpolator;
+
+import com.android.launcher3.Utilities;
+import com.android.launcher3.Workspace;
+
+/**
+ * Utility class to handle wallpaper scrolling along with workspace.
+ */
+public class WallpaperOffsetInterpolator implements Choreographer.FrameCallback {
+    private static final String TAG = "WPOffsetInterpolator";
+    private static final int ANIMATION_DURATION = 250;
+
+    // Don't use all the wallpaper for parallax until you have at least this many pages
+    private static final int MIN_PARALLAX_PAGE_SPAN = 3;
+
+    private final Choreographer mChoreographer;
+    private final Interpolator mInterpolator;
+    private final WallpaperManager mWallpaperManager;
+    private final Workspace mWorkspace;
+    private final boolean mIsRtl;
+
+    private IBinder mWindowToken;
+    private boolean mWallpaperIsLiveWallpaper;
+    private float mLastSetWallpaperOffsetSteps = 0;
+
+    private float mFinalOffset = 0.0f;
+    private float mCurrentOffset = 0.5f; // to force an initial update
+    private boolean mWaitingForUpdate;
+
+    private boolean mAnimating;
+    private long mAnimationStartTime;
+    private float mAnimationStartOffset;
+    int mNumScreens;
+    int mNumPagesForWallpaperParallax;
+
+    public WallpaperOffsetInterpolator(Workspace workspace) {
+        mChoreographer = Choreographer.getInstance();
+        mInterpolator = new DecelerateInterpolator(1.5f);
+
+        mWorkspace = workspace;
+        mWallpaperManager = WallpaperManager.getInstance(workspace.getContext());
+        mIsRtl = Utilities.isRtl(workspace.getResources());
+    }
+
+    @Override
+    public void doFrame(long frameTimeNanos) {
+        updateOffset(false);
+    }
+
+    private void updateOffset(boolean force) {
+        if (mWaitingForUpdate || force) {
+            mWaitingForUpdate = false;
+            if (computeScrollOffset() && mWindowToken != null) {
+                try {
+                    mWallpaperManager.setWallpaperOffsets(mWindowToken, getCurrX(), 0.5f);
+                    setWallpaperOffsetSteps();
+                } catch (IllegalArgumentException e) {
+                    Log.e(TAG, "Error updating wallpaper offset: " + e);
+                }
+            }
+        }
+    }
+
+    public boolean computeScrollOffset() {
+        final float oldOffset = mCurrentOffset;
+        if (mAnimating) {
+            long durationSinceAnimation = System.currentTimeMillis() - mAnimationStartTime;
+            float t0 = durationSinceAnimation / (float) ANIMATION_DURATION;
+            float t1 = mInterpolator.getInterpolation(t0);
+            mCurrentOffset = mAnimationStartOffset +
+                    (mFinalOffset - mAnimationStartOffset) * t1;
+            mAnimating = durationSinceAnimation < ANIMATION_DURATION;
+        } else {
+            mCurrentOffset = mFinalOffset;
+        }
+
+        if (Math.abs(mCurrentOffset - mFinalOffset) > 0.0000001f) {
+            scheduleUpdate();
+        }
+        if (Math.abs(oldOffset - mCurrentOffset) > 0.0000001f) {
+            return true;
+        }
+        return false;
+    }
+
+    public float wallpaperOffsetForScroll(int scroll) {
+        // TODO: do different behavior if it's  a live wallpaper?
+        // Don't use up all the wallpaper parallax until you have at least
+        // MIN_PARALLAX_PAGE_SPAN pages
+        int numScrollingPages = getNumScreensExcludingEmptyAndCustom();
+        int parallaxPageSpan;
+        if (mWallpaperIsLiveWallpaper) {
+            parallaxPageSpan = numScrollingPages - 1;
+        } else {
+            parallaxPageSpan = Math.max(MIN_PARALLAX_PAGE_SPAN, numScrollingPages - 1);
+        }
+        mNumPagesForWallpaperParallax = parallaxPageSpan;
+
+        if (mWorkspace.getChildCount() <= 1) {
+            if (mIsRtl) {
+                return 1 - 1.0f/mNumPagesForWallpaperParallax;
+            }
+            return 0;
+        }
+
+        // Exclude the leftmost page
+        int emptyExtraPages = numEmptyScreensToIgnore();
+        int firstIndex = mWorkspace.numCustomPages();
+        // Exclude the last extra empty screen (if we have > MIN_PARALLAX_PAGE_SPAN pages)
+        int lastIndex = mWorkspace.getChildCount() - 1 - emptyExtraPages;
+        if (mIsRtl) {
+            int temp = firstIndex;
+            firstIndex = lastIndex;
+            lastIndex = temp;
+        }
+
+        int firstPageScrollX = mWorkspace.getScrollForPage(firstIndex);
+        int scrollRange = mWorkspace.getScrollForPage(lastIndex) - firstPageScrollX;
+        if (scrollRange == 0) {
+            return 0;
+        } else {
+            // Sometimes the left parameter of the pages is animated during a layout transition;
+            // this parameter offsets it to keep the wallpaper from animating as well
+            int adjustedScroll =
+                    scroll - firstPageScrollX - mWorkspace.getLayoutTransitionOffsetForPage(0);
+            float offset = Math.min(1, adjustedScroll / (float) scrollRange);
+            offset = Math.max(0, offset);
+
+            // On RTL devices, push the wallpaper offset to the right if we don't have enough
+            // pages (ie if numScrollingPages < MIN_PARALLAX_PAGE_SPAN)
+            if (!mWallpaperIsLiveWallpaper && numScrollingPages < MIN_PARALLAX_PAGE_SPAN
+                    && mIsRtl) {
+                return offset * (parallaxPageSpan - numScrollingPages + 1) / parallaxPageSpan;
+            }
+            return offset * (numScrollingPages - 1) / parallaxPageSpan;
+        }
+    }
+
+    private float wallpaperOffsetForCurrentScroll() {
+        return wallpaperOffsetForScroll(mWorkspace.getScrollX());
+    }
+
+    private int numEmptyScreensToIgnore() {
+        int numScrollingPages = mWorkspace.getChildCount() - mWorkspace.numCustomPages();
+        if (numScrollingPages >= MIN_PARALLAX_PAGE_SPAN && mWorkspace.hasExtraEmptyScreen()) {
+            return 1;
+        } else {
+            return 0;
+        }
+    }
+
+    private int getNumScreensExcludingEmptyAndCustom() {
+        return mWorkspace.getChildCount() - numEmptyScreensToIgnore() - mWorkspace.numCustomPages();
+    }
+
+    public void syncWithScroll() {
+        float offset = wallpaperOffsetForCurrentScroll();
+        setFinalX(offset);
+        updateOffset(true);
+    }
+
+    public float getCurrX() {
+        return mCurrentOffset;
+    }
+
+    public float getFinalX() {
+        return mFinalOffset;
+    }
+
+    private void animateToFinal() {
+        mAnimating = true;
+        mAnimationStartOffset = mCurrentOffset;
+        mAnimationStartTime = System.currentTimeMillis();
+    }
+
+    private void setWallpaperOffsetSteps() {
+        // Set wallpaper offset steps (1 / (number of screens - 1))
+        float xOffset = 1.0f / mNumPagesForWallpaperParallax;
+        if (xOffset != mLastSetWallpaperOffsetSteps) {
+            mWallpaperManager.setWallpaperOffsetSteps(xOffset, 1.0f);
+            mLastSetWallpaperOffsetSteps = xOffset;
+        }
+    }
+
+    public void setFinalX(float x) {
+        scheduleUpdate();
+        mFinalOffset = Math.max(0f, Math.min(x, 1.0f));
+        if (getNumScreensExcludingEmptyAndCustom() != mNumScreens) {
+            if (mNumScreens > 0) {
+                // Don't animate if we're going from 0 screens
+                animateToFinal();
+            }
+            mNumScreens = getNumScreensExcludingEmptyAndCustom();
+        }
+    }
+
+    private void scheduleUpdate() {
+        if (!mWaitingForUpdate) {
+            mChoreographer.postFrameCallback(this);
+            mWaitingForUpdate = true;
+        }
+    }
+
+    public void jumpToFinal() {
+        mCurrentOffset = mFinalOffset;
+    }
+
+    public void onResume() {
+        mWallpaperIsLiveWallpaper = mWallpaperManager.getWallpaperInfo() != null;
+        // Force the wallpaper offset steps to be set again, because another app might have changed
+        // them
+        mLastSetWallpaperOffsetSteps = 0f;
+    }
+
+    public void setWindowToken(IBinder token) {
+        mWindowToken = token;
+    }
+}
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