fix: switch state sync problem

2017-02-04 10:14:58 +08:00
parent 5640b47663
commit 3fb16518e4
11 changed files with 205 additions and 106 deletions
--- a/app/src/main/java/com/stardust/util/StateObserver.java
+++ b/app/src/main/java/com/stardust/util/StateObserver.java
@@ -0,0 +1,125 @@
+package com.stardust.util;
+
+import android.content.SharedPreferences;
+import android.support.v7.widget.SwitchCompat;
+
+import java.lang.ref.WeakReference;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * Created by Stardust on 2017/2/3.
+ */
+
+public class StateObserver {
+
+    public interface OnStateChangedListener<T> {
+
+        void onStateChanged(T newState);
+
+        void initState(T state);
+    }
+
+
+    public static abstract class SimpleOnStateChangedListener<T> implements OnStateChangedListener<T> {
+
+        @Override
+        public void initState(T state) {
+            onStateChanged(state);
+        }
+    }
+
+    public interface OnBooleanStateChangedListener extends OnStateChangedListener<Boolean> {
+
+    }
+
+    public static abstract class SimpleOnBooleanStateChangedListener implements OnBooleanStateChangedListener {
+
+        @Override
+        public void initState(Boolean state) {
+            onStateChanged(state);
+        }
+    }
+
+
+    private final Map<String, List<OnStateChangedListener>> mKeyStateListenersMap = new HashMap<>();
+    private SharedPreferences mSharedPreferences;
+
+    public StateObserver(SharedPreferences sharedPreferences) {
+        mSharedPreferences = sharedPreferences;
+    }
+
+    public void register(final String key, SwitchCompat switchCompat) {
+        final WeakReference<SwitchCompat> switchCompatWeakReference = new WeakReference<>(switchCompat);
+        register(key, new SimpleOnBooleanStateChangedListener() {
+            @Override
+            public void onStateChanged(Boolean newState) {
+                if (switchCompatWeakReference.get() != null) {
+                    switchCompatWeakReference.get().setChecked(newState);
+                } else {
+                    unregister(key, this);
+                }
+            }
+        });
+    }
+
+    public <T> void register(String key, OnStateChangedListener<T> listener) {
+        T initialState = readState(key, listener);
+        if (initialState != null)
+            listener.initState(initialState);
+        synchronized (mKeyStateListenersMap) {
+            getListenerListOrCreateIfNotExists(key).add(listener);
+        }
+    }
+
+
+    private <T> void unregister(String key, OnStateChangedListener<T> stateChangedListener) {
+        synchronized (mKeyStateListenersMap) {
+            List<OnStateChangedListener> listeners = mKeyStateListenersMap.get(key);
+            if (listeners == null) {
+                return;
+            }
+            listeners.remove(stateChangedListener);
+        }
+    }
+
+    public <T> void setState(String key, T state) {
+        synchronized (mKeyStateListenersMap) {
+            List<OnStateChangedListener> listeners = mKeyStateListenersMap.get(key);
+            if (listeners == null || listeners.isEmpty()) {
+                return;
+            }
+            if (listeners.get(0) instanceof OnBooleanStateChangedListener) {
+                mSharedPreferences.edit().putBoolean(key, (Boolean) state).apply();
+                notifyBooleanStateChanged(listeners, (Boolean) state);
+            }
+        }
+    }
+
+    private void notifyBooleanStateChanged(List<OnStateChangedListener> listeners, boolean state) {
+        for (OnStateChangedListener listener : listeners) {
+            listener.onStateChanged(state);
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    protected <T> T readState(String key, OnStateChangedListener<T> listener) {
+        if (listener instanceof OnBooleanStateChangedListener) {
+            return mSharedPreferences.contains(key) ? (T) Boolean.valueOf(mSharedPreferences.getBoolean(key, false)) : null;
+        }
+        return null;
+    }
+
+    private List<OnStateChangedListener> getListenerListOrCreateIfNotExists(String key) {
+        List<OnStateChangedListener> listeners = mKeyStateListenersMap.get(key);
+        if (listeners == null) {
+            listeners = new ArrayList<>();
+            mKeyStateListenersMap.put(key, listeners);
+        }
+        return listeners;
+    }
+
+
+}