예제 #1
0
    /**
     * Adjusts the given row if possible to fit within the layout span. By default this will try to
     * find the highest break weight possible nearest the end of the row. If a forced break is
     * encountered, the break will be positioned there.
     *
     * @param rowIndex the row to adjust to the current layout span.
     * @param desiredSpan the current layout span >= 0
     * @param x the location r starts at.
     */
    protected void adjustRow(FlowView fv, int rowIndex, int desiredSpan, int x) {
      final int flowAxis = fv.getFlowAxis();
      View r = fv.getView(rowIndex);
      int n = r.getViewCount();
      int span = 0;
      int bestWeight = BadBreakWeight;
      int bestSpan = 0;
      int bestIndex = -1;
      int bestOffset = 0;
      View v;
      for (int i = 0; i < n; i++) {
        v = r.getView(i);
        int spanLeft = desiredSpan - span;

        int w = v.getBreakWeight(flowAxis, x + span, spanLeft);
        if ((w >= bestWeight) && (w > BadBreakWeight)) {
          bestWeight = w;
          bestIndex = i;
          bestSpan = span;
          if (w >= ForcedBreakWeight) {
            // it's a forced break, so there is
            // no point in searching further.
            break;
          }
        }
        span += v.getPreferredSpan(flowAxis);
      }
      if (bestIndex < 0) {
        // there is nothing that can be broken, leave
        // it in it's current state.
        return;
      }

      // Break the best candidate view, and patch up the row.
      int spanLeft = desiredSpan - bestSpan;
      v = r.getView(bestIndex);
      v = v.breakView(flowAxis, v.getStartOffset(), x + bestSpan, spanLeft);
      View[] va = new View[1];
      va[0] = v;
      View lv = getLogicalView(fv);
      for (int i = bestIndex; i < n; i++) {
        View tmpView = r.getView(i);
        if (contains(lv, tmpView)) {
          tmpView.setParent(lv);
        } else if (tmpView.getViewCount() > 0) {
          recursiveReparent(tmpView, lv);
        }
      }
      r.replace(bestIndex, n - bestIndex, va);
    }
예제 #2
0
    /**
     * Update the flow on the given FlowView. By default, this causes all of the rows (child views)
     * to be rebuilt to match the given constraints for each row. This is called by a
     * FlowView.layout to update the child views in the flow.
     *
     * @param fv the view to reflow
     */
    public void layout(FlowView fv) {
      int p0 = fv.getStartOffset();
      int p1 = fv.getEndOffset();

      // we want to preserve all views from the logicalView from being
      // removed
      View lv = getLogicalView(fv);
      int n = lv.getViewCount();
      for (int i = 0; i < n; i++) {
        View v = lv.getView(i);
        v.setParent(lv);
      }
      fv.removeAll();
      for (int rowIndex = 0; p0 < p1; rowIndex++) {
        View row = fv.createRow();
        fv.append(row);

        // layout the row to the current span.  If nothing fits,
        // force something.
        int next = layoutRow(fv, rowIndex, p0);
        if (row.getViewCount() == 0) {
          row.append(createView(fv, p0, Integer.MAX_VALUE, rowIndex));
          next = row.getEndOffset();
        }
        if (next <= p0) {
          throw new StateInvariantError("infinite loop in formatting");
        } else {
          p0 = next;
        }
      }
    }
예제 #3
0
 private boolean contains(View logicalView, View v) {
   int n = logicalView.getViewCount();
   for (int i = 0; i < n; i++) {
     if (logicalView.getView(i) == v) {
       return true;
     }
   }
   return false;
 }
예제 #4
0
 private void recursiveReparent(View v, View logicalView) {
   int n = v.getViewCount();
   for (int i = 0; i < n; i++) {
     View tmpView = v.getView(i);
     if (contains(logicalView, tmpView)) {
       tmpView.setParent(logicalView);
     } else {
       recursiveReparent(tmpView, logicalView);
     }
   }
 }
예제 #5
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    /**
     * Creates a view that can be used to represent the current piece of the flow. This can be
     * either an entire view from the logical view, or a fragment of the logical view.
     *
     * @param fv the view holding the flow
     * @param startOffset the start location for the view being created
     * @param spanLeft the about of span left to fill in the row
     * @param rowIndex the row the view will be placed into
     */
    protected View createView(FlowView fv, int startOffset, int spanLeft, int rowIndex) {
      // Get the child view that contains the given starting position
      View lv = getLogicalView(fv);
      int childIndex = lv.getViewIndex(startOffset, Position.Bias.Forward);
      View v = lv.getView(childIndex);
      if (startOffset == v.getStartOffset()) {
        // return the entire view
        return v;
      }

      // return a fragment.
      v = v.createFragment(startOffset, v.getEndOffset());
      return v;
    }