| /* |
| * Copyright (C) 2010 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 android.app; |
| |
| import android.animation.LayoutTransition; |
| import android.app.FragmentManager.BackStackEntry; |
| import android.content.Context; |
| import android.util.AttributeSet; |
| import android.view.LayoutInflater; |
| import android.view.View; |
| import android.view.ViewGroup; |
| import android.widget.LinearLayout; |
| import android.widget.TextView; |
| |
| /** |
| * Helper class for showing "bread crumbs" representing the fragment |
| * stack in an activity. This is intended to be used with |
| * {@link ActionBar#setCustomNavigationMode(View) |
| * ActionBar.setCustomNavigationMode(View)} to place the bread crumbs in |
| * the navigation area of the action bar. |
| * |
| * <p>The default style for this view is |
| * {@link android.R.style#Widget_FragmentBreadCrumbs}. |
| */ |
| public class FragmentBreadCrumbs extends ViewGroup |
| implements FragmentManager.OnBackStackChangedListener { |
| Activity mActivity; |
| LayoutInflater mInflater; |
| LinearLayout mContainer; |
| |
| // Hahah |
| BackStackRecord mTopEntry; |
| |
| public FragmentBreadCrumbs(Context context) { |
| this(context, null); |
| } |
| |
| public FragmentBreadCrumbs(Context context, AttributeSet attrs) { |
| this(context, attrs, android.R.style.Widget_FragmentBreadCrumbs); |
| } |
| |
| public FragmentBreadCrumbs(Context context, AttributeSet attrs, int defStyle) { |
| super(context, attrs, defStyle); |
| } |
| |
| /** |
| * Attach the bread crumbs to their activity. This must be called once |
| * when creating the bread crumbs. |
| */ |
| public void setActivity(Activity a) { |
| mActivity = a; |
| mInflater = (LayoutInflater)a.getSystemService(Context.LAYOUT_INFLATER_SERVICE); |
| mContainer = (LinearLayout)mInflater.inflate( |
| com.android.internal.R.layout.fragment_bread_crumbs, |
| this, false); |
| addView(mContainer); |
| a.getFragmentManager().addOnBackStackChangedListener(this); |
| updateCrumbs(); |
| setLayoutTransition(new LayoutTransition()); |
| } |
| |
| /** |
| * Set a custom title for the bread crumbs. This will be the first entry |
| * shown at the left, representing the root of the bread crumbs. If the |
| * title is null, it will not be shown. |
| */ |
| public void setTitle(CharSequence title, CharSequence shortTitle) { |
| if (title == null) { |
| mTopEntry = null; |
| } else { |
| mTopEntry = new BackStackRecord((FragmentManagerImpl) |
| mActivity.getFragmentManager()); |
| mTopEntry.setBreadCrumbTitle(title); |
| mTopEntry.setBreadCrumbShortTitle(shortTitle); |
| } |
| updateCrumbs(); |
| } |
| |
| @Override |
| protected void onLayout(boolean changed, int l, int t, int r, int b) { |
| // Eventually we should implement our own layout of the views, |
| // rather than relying on a linear layout. |
| final int childCount = getChildCount(); |
| for (int i = 0; i < childCount; i++) { |
| final View child = getChildAt(i); |
| |
| int childRight = mPaddingLeft + child.getMeasuredWidth() - mPaddingRight; |
| int childBottom = mPaddingTop + child.getMeasuredHeight() - mPaddingBottom; |
| child.layout(mPaddingLeft, mPaddingTop, childRight, childBottom); |
| } |
| } |
| |
| @Override |
| protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { |
| final int count = getChildCount(); |
| |
| int maxHeight = 0; |
| int maxWidth = 0; |
| |
| // Find rightmost and bottom-most child |
| for (int i = 0; i < count; i++) { |
| final View child = getChildAt(i); |
| if (child.getVisibility() != GONE) { |
| measureChild(child, widthMeasureSpec, heightMeasureSpec); |
| maxWidth = Math.max(maxWidth, child.getMeasuredWidth()); |
| maxHeight = Math.max(maxHeight, child.getMeasuredHeight()); |
| } |
| } |
| |
| // Account for padding too |
| maxWidth += mPaddingLeft + mPaddingRight; |
| maxHeight += mPaddingTop + mPaddingBottom; |
| |
| // Check against our minimum height and width |
| maxHeight = Math.max(maxHeight, getSuggestedMinimumHeight()); |
| maxWidth = Math.max(maxWidth, getSuggestedMinimumWidth()); |
| |
| setMeasuredDimension(resolveSize(maxWidth, widthMeasureSpec), |
| resolveSize(maxHeight, heightMeasureSpec)); |
| } |
| |
| @Override |
| public void onBackStackChanged() { |
| updateCrumbs(); |
| } |
| |
| void updateCrumbs() { |
| FragmentManager fm = mActivity.getFragmentManager(); |
| int numEntries = fm.countBackStackEntries(); |
| int numViews = mContainer.getChildCount(); |
| for (int i = mTopEntry != null ? -1 : 0; i < numEntries; i++) { |
| BackStackEntry bse = i == -1 ? mTopEntry : fm.getBackStackEntry(i); |
| int viewI = mTopEntry != null ? i + 1 : i; |
| if (viewI < numViews) { |
| View v = mContainer.getChildAt(viewI); |
| Object tag = v.getTag(); |
| if (tag != bse) { |
| for (int j = viewI; j < numViews; j++) { |
| mContainer.removeViewAt(viewI); |
| } |
| numViews = viewI; |
| } |
| } |
| if (viewI >= numViews) { |
| View item = mInflater.inflate( |
| com.android.internal.R.layout.fragment_bread_crumb_item, |
| this, false); |
| TextView text = (TextView)item.findViewById(com.android.internal.R.id.title); |
| text.setText(bse.getBreadCrumbTitle()); |
| item.setTag(bse); |
| if (viewI == 0) { |
| text.setCompoundDrawables(null, null, null, null); |
| } |
| mContainer.addView(item); |
| item.setOnClickListener(mOnClickListener); |
| } |
| } |
| int viewI = mTopEntry != null ? numEntries + 1 : numEntries; |
| numViews = mContainer.getChildCount(); |
| while (numViews > viewI) { |
| mContainer.removeViewAt(numViews-1); |
| numViews--; |
| } |
| } |
| |
| private OnClickListener mOnClickListener = new OnClickListener() { |
| public void onClick(View v) { |
| if (v.getTag() instanceof BackStackEntry) { |
| BackStackEntry bse = (BackStackEntry) v.getTag(); |
| mActivity.getFragmentManager().popBackStack(bse.getId(), |
| bse == mTopEntry? FragmentManager.POP_BACK_STACK_INCLUSIVE : 0); |
| } |
| } |
| }; |
| } |