Back-port new fragment detach APIs from support lib.
This allow a much cleaner implementation of things like the
fragment pager class.
Change-Id: I433be3d6c24c9a059d908d442bcfddbf1e8e57e5
diff --git a/api/current.txt b/api/current.txt
index 9d593d8..374c415 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -2923,8 +2923,10 @@
method public abstract android.app.FragmentTransaction add(int, android.app.Fragment);
method public abstract android.app.FragmentTransaction add(int, android.app.Fragment, java.lang.String);
method public abstract android.app.FragmentTransaction addToBackStack(java.lang.String);
+ method public abstract android.app.FragmentTransaction attach(android.app.Fragment);
method public abstract int commit();
method public abstract int commitAllowingStateLoss();
+ method public abstract android.app.FragmentTransaction detach(android.app.Fragment);
method public abstract android.app.FragmentTransaction disallowAddToBackStack();
method public abstract android.app.FragmentTransaction hide(android.app.Fragment);
method public abstract boolean isAddToBackStackAllowed();
diff --git a/core/java/android/app/BackStackRecord.java b/core/java/android/app/BackStackRecord.java
index 850f56a..e5a7980 100644
--- a/core/java/android/app/BackStackRecord.java
+++ b/core/java/android/app/BackStackRecord.java
@@ -173,6 +173,8 @@
static final int OP_REMOVE = 3;
static final int OP_HIDE = 4;
static final int OP_SHOW = 5;
+ static final int OP_DETACH = 6;
+ static final int OP_ATTACH = 7;
static final class Op {
Op next;
@@ -416,6 +418,32 @@
return this;
}
+ public FragmentTransaction detach(Fragment fragment) {
+ //if (fragment.mImmediateActivity == null) {
+ // throw new IllegalStateException("Fragment not added: " + fragment);
+ //}
+
+ Op op = new Op();
+ op.cmd = OP_DETACH;
+ op.fragment = fragment;
+ addOp(op);
+
+ return this;
+ }
+
+ public FragmentTransaction attach(Fragment fragment) {
+ //if (fragment.mImmediateActivity == null) {
+ // throw new IllegalStateException("Fragment not added: " + fragment);
+ //}
+
+ Op op = new Op();
+ op.cmd = OP_ATTACH;
+ op.fragment = fragment;
+ addOp(op);
+
+ return this;
+ }
+
public FragmentTransaction setCustomAnimations(int enter, int exit) {
return setCustomAnimations(enter, exit, 0, 0);
}
@@ -589,6 +617,16 @@
f.mNextAnim = op.enterAnim;
mManager.showFragment(f, mTransition, mTransitionStyle);
} break;
+ case OP_DETACH: {
+ Fragment f = op.fragment;
+ f.mNextAnim = op.exitAnim;
+ mManager.detachFragment(f, mTransition, mTransitionStyle);
+ } break;
+ case OP_ATTACH: {
+ Fragment f = op.fragment;
+ f.mNextAnim = op.enterAnim;
+ mManager.attachFragment(f, mTransition, mTransitionStyle);
+ } break;
default: {
throw new IllegalArgumentException("Unknown cmd: " + op.cmd);
}
@@ -655,6 +693,16 @@
mManager.hideFragment(f,
FragmentManagerImpl.reverseTransit(mTransition), mTransitionStyle);
} break;
+ case OP_DETACH: {
+ Fragment f = op.fragment;
+ mManager.attachFragment(f,
+ FragmentManagerImpl.reverseTransit(mTransition), mTransitionStyle);
+ } break;
+ case OP_ATTACH: {
+ Fragment f = op.fragment;
+ mManager.detachFragment(f,
+ FragmentManagerImpl.reverseTransit(mTransition), mTransitionStyle);
+ } break;
default: {
throw new IllegalArgumentException("Unknown cmd: " + op.cmd);
}
diff --git a/core/java/android/app/Fragment.java b/core/java/android/app/Fragment.java
index 53dc7c8..a528a1aa 100644
--- a/core/java/android/app/Fragment.java
+++ b/core/java/android/app/Fragment.java
@@ -52,6 +52,7 @@
final int mContainerId;
final String mTag;
final boolean mRetainInstance;
+ final boolean mDetached;
final Bundle mArguments;
Bundle mSavedFragmentState;
@@ -66,6 +67,7 @@
mContainerId = frag.mContainerId;
mTag = frag.mTag;
mRetainInstance = frag.mRetainInstance;
+ mDetached = frag.mDetached;
mArguments = frag.mArguments;
}
@@ -77,6 +79,7 @@
mContainerId = in.readInt();
mTag = in.readString();
mRetainInstance = in.readInt() != 0;
+ mDetached = in.readInt() != 0;
mArguments = in.readBundle();
mSavedFragmentState = in.readBundle();
}
@@ -103,6 +106,7 @@
mInstance.mContainerId = mContainerId;
mInstance.mTag = mTag;
mInstance.mRetainInstance = mRetainInstance;
+ mInstance.mDetached = mDetached;
mInstance.mFragmentManager = activity.mFragments;
return mInstance;
@@ -120,6 +124,7 @@
dest.writeInt(mContainerId);
dest.writeString(mTag);
dest.writeInt(mRetainInstance ? 1 : 0);
+ dest.writeInt(mDetached ? 1 : 0);
dest.writeBundle(mArguments);
dest.writeBundle(mSavedFragmentState);
}
@@ -404,6 +409,9 @@
// from the user.
boolean mHidden;
+ // Set to true when the app has requested that this fragment be detached.
+ boolean mDetached;
+
// If set this fragment would like its instance retained across
// configuration changes.
boolean mRetainInstance;
@@ -511,23 +519,27 @@
}
}
- void restoreViewState() {
+ final void restoreViewState() {
if (mSavedViewState != null) {
mView.restoreHierarchyState(mSavedViewState);
mSavedViewState = null;
}
}
- void setIndex(int index) {
+ final void setIndex(int index) {
mIndex = index;
mWho = "android:fragment:" + mIndex;
}
- void clearIndex() {
+ final void clearIndex() {
mIndex = -1;
mWho = null;
}
+ final boolean isInBackStack() {
+ return mBackStackNesting > 0;
+ }
+
/**
* Subclasses can not override equals().
*/
@@ -1280,6 +1292,7 @@
writer.print(" mFromLayout="); writer.print(mFromLayout);
writer.print(" mInLayout="); writer.println(mInLayout);
writer.print(prefix); writer.print("mHidden="); writer.print(mHidden);
+ writer.print(" mDetached="); writer.print(mDetached);
writer.print(" mRetainInstance="); writer.print(mRetainInstance);
writer.print(" mRetaining="); writer.print(mRetaining);
writer.print(" mHasMenu="); writer.println(mHasMenu);
diff --git a/core/java/android/app/FragmentManager.java b/core/java/android/app/FragmentManager.java
index ab60cf0..1eaca3b 100644
--- a/core/java/android/app/FragmentManager.java
+++ b/core/java/android/app/FragmentManager.java
@@ -971,32 +971,36 @@
if (mAdded == null) {
mAdded = new ArrayList<Fragment>();
}
- mAdded.add(fragment);
- makeActive(fragment);
if (DEBUG) Log.v(TAG, "add: " + fragment);
- fragment.mAdded = true;
- fragment.mRemoving = false;
- if (fragment.mHasMenu) {
- mNeedMenuInvalidate = true;
- }
- if (moveToStateNow) {
- moveToState(fragment);
+ makeActive(fragment);
+ if (!fragment.mDetached) {
+ mAdded.add(fragment);
+ fragment.mAdded = true;
+ fragment.mRemoving = false;
+ if (fragment.mHasMenu) {
+ mNeedMenuInvalidate = true;
+ }
+ if (moveToStateNow) {
+ moveToState(fragment);
+ }
}
}
public void removeFragment(Fragment fragment, int transition, int transitionStyle) {
if (DEBUG) Log.v(TAG, "remove: " + fragment + " nesting=" + fragment.mBackStackNesting);
- mAdded.remove(fragment);
- final boolean inactive = fragment.mBackStackNesting <= 0;
- if (fragment.mHasMenu) {
- mNeedMenuInvalidate = true;
- }
- fragment.mAdded = false;
- fragment.mRemoving = true;
- moveToState(fragment, inactive ? Fragment.INITIALIZING : Fragment.CREATED,
- transition, transitionStyle);
- if (inactive) {
- makeInactive(fragment);
+ final boolean inactive = !fragment.isInBackStack();
+ if (!fragment.mDetached || inactive) {
+ mAdded.remove(fragment);
+ if (fragment.mHasMenu) {
+ mNeedMenuInvalidate = true;
+ }
+ fragment.mAdded = false;
+ fragment.mRemoving = true;
+ moveToState(fragment, inactive ? Fragment.INITIALIZING : Fragment.CREATED,
+ transition, transitionStyle);
+ if (inactive) {
+ makeInactive(fragment);
+ }
}
}
@@ -1052,6 +1056,39 @@
}
}
+ public void detachFragment(Fragment fragment, int transition, int transitionStyle) {
+ if (DEBUG) Log.v(TAG, "detach: " + fragment);
+ if (!fragment.mDetached) {
+ fragment.mDetached = true;
+ if (fragment.mAdded) {
+ // We are not already in back stack, so need to remove the fragment.
+ mAdded.remove(fragment);
+ if (fragment.mHasMenu) {
+ mNeedMenuInvalidate = true;
+ }
+ fragment.mAdded = false;
+ fragment.mRemoving = true;
+ moveToState(fragment, Fragment.CREATED, transition, transitionStyle);
+ }
+ }
+ }
+
+ public void attachFragment(Fragment fragment, int transition, int transitionStyle) {
+ if (DEBUG) Log.v(TAG, "attach: " + fragment);
+ if (fragment.mDetached) {
+ fragment.mDetached = false;
+ if (!fragment.mAdded) {
+ mAdded.add(fragment);
+ fragment.mAdded = true;
+ fragment.mRemoving = false;
+ if (fragment.mHasMenu) {
+ mNeedMenuInvalidate = true;
+ }
+ moveToState(fragment, mCurState, transition, transitionStyle);
+ }
+ }
+ }
+
public Fragment findFragmentById(int id) {
if (mActive != null) {
// First look through added fragments.
diff --git a/core/java/android/app/FragmentTransaction.java b/core/java/android/app/FragmentTransaction.java
index 68600b3..c1f3cd6 100644
--- a/core/java/android/app/FragmentTransaction.java
+++ b/core/java/android/app/FragmentTransaction.java
@@ -87,6 +87,31 @@
public abstract FragmentTransaction show(Fragment fragment);
/**
+ * Detach the given fragment from the UI. This is the same state as
+ * when it is put on the back stack: the fragment is removed from
+ * the UI, however its state is still being actively managed by the
+ * fragment manager. When going into this state its view hierarchy
+ * is destroyed.
+ *
+ * @param fragment The fragment to be detached.
+ *
+ * @return Returns the same FragmentTransaction instance.
+ */
+ public abstract FragmentTransaction detach(Fragment fragment);
+
+ /**
+ * Re-attach a fragment after it had previously been deatched from
+ * the UI with {@link #detach(Fragment)}. This
+ * causes its view hierarchy to be re-created, attached to the UI,
+ * and displayed.
+ *
+ * @param fragment The fragment to be attached.
+ *
+ * @return Returns the same FragmentTransaction instance.
+ */
+ public abstract FragmentTransaction attach(Fragment fragment);
+
+ /**
* @return <code>true</code> if this transaction contains no operations,
* <code>false</code> otherwise.
*/