Allow custom transitions from XML. (44d66384) · Commits · e / os / android_frameworks_base

core/java/android/transition/Transition.java

+5 −0

Original line number	Diff line number	Diff line
		@@ -73,6 +73,11 @@ import java.util.List;
		*
		* {@sample development/samples/ApiDemos/res/transition/explode_move_together.xml MultipleTransform}
		*
		* <p>Custom transition classes may be instantiated with a <code>transition</code> tag:</p>
		* <pre><transition class="my.app.transition.CustomTransition"/></pre>
		* <p>Custom transition classes loaded from XML must have a public nullary (no argument)
		* constructor.</p>
		*
		* <p>Note that attributes for the transition are not required, just as they are
		* optional when declared in code; Transitions created from XML resources will use
		* the same defaults as their code-created equivalents. Here is a slightly more

+25 −0

Original line number	Diff line number	Diff line
		@@ -182,6 +182,8 @@ public class TransitionInflater {
		createTransitionFromXml(parser, attrs, ((TransitionSet) transition));
		a.recycle();
		newTransition = true;
		} else if ("transition".equals(name)) {
		transition = createCustomTransition(attrs);
		} else if ("targets".equals(name)) {
		if (parser.getDepth() - 1 > depth && transition != null) {
		// We're inside the child tag - add targets to the child
		@@ -206,6 +208,29 @@ public class TransitionInflater {
		return transition;
		}

		private Transition createCustomTransition(AttributeSet attrs) {
		String className = attrs.getAttributeValue(null, "class");

		if (className == null) {
		throw new RuntimeException("transition tag must have a 'class' attribute");
		}

		try {
		Class c = Class.forName(className);
		if (!Transition.class.isAssignableFrom(c)) {
		throw new RuntimeException("transition class must be a Transition: " + className);
		}
		return (Transition) c.newInstance();
		} catch (InstantiationException e) {
		throw new RuntimeException("Could not instantiate transition class", e);
		} catch (IllegalAccessException e) {
		throw new RuntimeException("Could not access default constructor for transition class "
		+ className, e);
		} catch (ClassNotFoundException e) {
		throw new RuntimeException("Could not find transition class " + className, e);
		}
		}

		private Slide createSlideTransition(AttributeSet attrs) {
		TypedArray a = mContext.obtainStyledAttributes(attrs,
		com.android.internal.R.styleable.Slide);