Bindings: Move to a separate package

These are really app-independent reusable classes. Moving them to a separate package helps avoid polluting the main app package, and makes them easier to upgrade. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2017-11-07 23:34:22 -06:00
parent 6945aa1107
commit 6231bb18ac
9 changed files with 20 additions and 8 deletions
@@ -0,0 +1,105 @@
+package com.wireguard.android.bindings;
+
+import android.databinding.BindingAdapter;
+import android.databinding.ObservableList;
+import android.databinding.adapters.ListenerUtil;
+import android.graphics.Typeface;
+import android.text.InputFilter;
+import android.widget.LinearLayout;
+import android.widget.ListView;
+import android.widget.TextView;
+
+import com.wireguard.android.R;
+
+/**
+ * Static methods for use by generated code in the Android data binding library.
+ */
+
+@SuppressWarnings("unused")
+public final class BindingAdapters {
+    @BindingAdapter({"items", "layout"})
+    public static <T> void setItems(final LinearLayout view,
+                                    final ObservableList<T> oldList, final int oldLayoutId,
+                                    final ObservableList<T> newList, final int newLayoutId) {
+        if (oldList == newList && oldLayoutId == newLayoutId)
+            return;
+        ItemChangeListener<T> listener = ListenerUtil.getListener(view, R.id.item_change_listener);
+        // If the layout changes, any existing listener must be replaced.
+        if (listener != null && oldList != null && oldLayoutId != newLayoutId) {
+            listener.setList(null);
+            listener = null;
+        }
+        // Avoid adding a listener when there is no new list or layout.
+        if (newList == null || newLayoutId == 0)
+            return;
+        if (listener == null) {
+            listener = new ItemChangeListener<>(view, newLayoutId);
+            ListenerUtil.trackListener(view, listener, R.id.item_change_listener);
+        }
+        // Either the list changed, or this is an entirely new listener because the layout changed.
+        listener.setList(newList);
+    }
+
+    @BindingAdapter({"items", "layout"})
+    public static <T> void setItems(final ListView view,
+                                    final ObservableList<T> oldList, final int oldLayoutId,
+                                    final ObservableList<T> newList, final int newLayoutId) {
+        // Remove any existing binding when there is no new list or layout.
+        if (newList == null || newLayoutId == 0) {
+            view.setAdapter(null);
+            return;
+        }
+        // The ListAdapter interface is not generic, so this cannot be checked.
+        @SuppressWarnings("unchecked")
+        ObservableListAdapter<T> adapter = (ObservableListAdapter<T>) view.getAdapter();
+        // If the layout changes, any existing adapter must be replaced.
+        if (newLayoutId != oldLayoutId)
+            adapter = null;
+        // Add a new binding if there was none, or if it must be replaced due to a layout change.
+        if (adapter == null) {
+            view.setAdapter(new ObservableListAdapter<>(view.getContext(), newLayoutId, newList));
+        } else if (newList != oldList) {
+            // Changing the list only requires modifying the existing adapter.
+            adapter.setList(newList);
+        }
+    }
+
+    @BindingAdapter({"items", "layout"})
+    public static <K extends Comparable<K>, V> void setItems(
+            final ListView view,
+            final ObservableSortedMap<K, V> oldMap, final int oldLayoutId,
+            final ObservableSortedMap<K, V> newMap, final int newLayoutId) {
+        // Remove any existing binding when there is no new map or layout.
+        if (newMap == null || newLayoutId == 0) {
+            view.setAdapter(null);
+            return;
+        }
+        // The ListAdapter interface is not generic, so this cannot be checked.
+        @SuppressWarnings("unchecked")
+        ObservableMapAdapter<K, V> adapter = (ObservableMapAdapter<K, V>) view.getAdapter();
+        // If the layout changes, any existing adapter must be replaced.
+        if (newLayoutId != oldLayoutId)
+            adapter = null;
+        // Add a new binding if there was none, or if it must be replaced due to a layout change.
+        if (adapter == null) {
+            view.setAdapter(new ObservableMapAdapter<>(view.getContext(), newLayoutId, newMap));
+        } else if (newMap != oldMap) {
+            // Changing the list only requires modifying the existing adapter.
+            adapter.setMap(newMap);
+        }
+    }
+
+    @BindingAdapter({"filter"})
+    public static void setFilter(final TextView view, final InputFilter filter) {
+        view.setFilters(new InputFilter[]{filter});
+    }
+
+    @BindingAdapter({"android:textStyle"})
+    public static void setTextStyle(final TextView view, final Typeface typeface) {
+        view.setTypeface(typeface);
+    }
+
+    private BindingAdapters() {
+        // Prevent instantiation.
+    }
+}