Merge "Add validation code for GridLayout.LayoutParams" into jb-dev (c8b7747b) · Commits · e / os / android_frameworks_base

core/java/android/widget/GridLayout.java

+49 −15

Original line number	Diff line number	Diff line
		@@ -581,7 +581,7 @@ public class GridLayout extends ViewGroup {
		}

		private int getDefaultMargin(View c, boolean isAtEdge, boolean horizontal, boolean leading) {
		return /isAtEdge ? DEFAULT_CONTAINER_MARGIN :/ getDefaultMargin(c, horizontal, leading);
		return isAtEdge ? DEFAULT_CONTAINER_MARGIN : getDefaultMargin(c, horizontal, leading);
		}

		private int getDefaultMargin(View c, LayoutParams p, boolean horizontal, boolean leading) {
		@@ -733,6 +733,11 @@ public class GridLayout extends ViewGroup {
		@Override
		protected void onSetLayoutParams(View child, ViewGroup.LayoutParams layoutParams) {
		super.onSetLayoutParams(child, layoutParams);

		if (!checkLayoutParams(layoutParams)) {
		handleInvalidParams("supplied LayoutParams are of the wrong type");
		}

		invalidateStructure();
		}

		@@ -740,6 +745,43 @@ public class GridLayout extends ViewGroup {
		return (LayoutParams) c.getLayoutParams();
		}

		private static void handleInvalidParams(String msg) {
		throw new IllegalArgumentException(msg + ". ");
		}

		private void checkLayoutParams(LayoutParams lp, boolean horizontal) {
		String groupName = horizontal ? "column" : "row";
		Spec spec = horizontal ? lp.columnSpec : lp.rowSpec;
		Interval span = spec.span;
		if (span.min != UNDEFINED && span.min < 0) {
		handleInvalidParams(groupName + " indices must be positive");
		}
		Axis axis = horizontal ? horizontalAxis : verticalAxis;
		int count = axis.definedCount;
		if (count != UNDEFINED) {
		if (span.max > count) {
		handleInvalidParams(groupName +
		" indices (start + span) mustn't exceed the " + groupName + " count");
		}
		if (span.size() > count) {
		handleInvalidParams(groupName + " span mustn't exceed the " + groupName + " count");
		}
		}
		}

		@Override
		protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {
		if (!(p instanceof LayoutParams)) {
		return false;
		}
		LayoutParams lp = (LayoutParams) p;

		checkLayoutParams(lp, true);
		checkLayoutParams(lp, false);

		return true;
		}

		@Override
		protected LayoutParams generateDefaultLayoutParams() {
		return new LayoutParams();
		@@ -1143,6 +1185,7 @@ public class GridLayout extends ViewGroup {
		Interval span = spec.span;
		result = max(result, span.min);
		result = max(result, span.max);
		result = max(result, span.size());
		}
		return result == -1 ? UNDEFINED : result;
		}
		@@ -1159,6 +1202,11 @@ public class GridLayout extends ViewGroup {
		}

		public void setCount(int count) {
		if (count != UNDEFINED && count < getMaxIndex()) {
		handleInvalidParams((horizontal ? "column" : "row") +
		"Count must be greater than or equal to the maximum of all grid indices " +
		"(and spans) defined in the LayoutParams of each child");
		}
		this.definedCount = count;
		}

		@@ -1478,20 +1526,6 @@ public class GridLayout extends ViewGroup {
		This is a special case of the Linear Programming problem that is, in turn,
		equivalent to the single-source shortest paths problem on a digraph, for
		which the O(n^2) Bellman-Ford algorithm the most commonly used general solution.

		Other algorithms are faster in the case where no arcs have negative weights
		but allowing negative weights turns out to be the same as accommodating maximum
		size requirements as well as minimum ones.

		Bellman-Ford works by iteratively 'relaxing' constraints over all nodes (an O(N)
		process) and performing this step N times. Proof of correctness hinges on the
		fact that there can be no negative weight chains of length > N - unless a
		'negative weight loop' exists. The algorithm catches this case in a final
		checking phase that reports failure.

		By topologically sorting the nodes and checking this condition at each step
		typical layout problems complete after the first iteration and the algorithm
		completes in O(N) steps with very low constants.
		*/
		private void solve(Arc[] arcs, int[] locations) {
		String axisName = horizontal ? "horizontal" : "vertical";