Migrate to opoc/basefragment; Fix redundant casts

app/src/main/java/net/gsantner/opoc/activity/GsFragmentBase.java

@@ -0,0 +1,129 @@
+/*#######################################################
+ *
+ *   Maintained by Gregor Santner, 2017-
+ *   https://gsantner.net/
+ *
+ *   License: Apache 2.0
+ *  https://github.com/gsantner/opoc/#licensing
+ *  https://www.apache.org/licenses/LICENSE-2.0
+ *
+#########################################################*/
+package net.gsantner.opoc.activity;
+
+import android.content.Context;
+import android.os.Bundle;
+import android.support.annotation.LayoutRes;
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+import android.support.v4.app.Fragment;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+
+import net.gsantner.opoc.util.ContextUtils;
+
+import butterknife.ButterKnife;
+
+/**
+ * A common base fragment to extend from
+ */
+public abstract class GsFragmentBase extends Fragment {
+    private boolean _fragmentFirstTimeVisible = true;
+    private final Object _fragmentFirstTimeVisibleSync = new Object();
+
+    protected ContextUtils _cu;
+    protected Bundle _savedInstanceState = null;
+
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setHasOptionsMenu(true);
+    }
+
+    /**
+     * Inflate the fragments layout. Don't override this method, just supply the needed
+     * {@link LayoutRes} via abstract method {@link #getLayoutResId()}, super does the rest
+     */
+    @Deprecated
+    @Nullable
+    @Override
+    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
+        _cu = new ContextUtils(inflater.getContext());
+        _cu.setAppLanguage(getAppLanguage());
+        _savedInstanceState = savedInstanceState;
+        View view = inflater.inflate(getLayoutResId(), container, false);
+        ButterKnife.bind(this, view);
+        return view;
+    }
+
+    @Override
+    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
+        super.onViewCreated(view, savedInstanceState);
+        view.postDelayed(() -> {
+            synchronized (_fragmentFirstTimeVisibleSync) {
+                if (getUserVisibleHint() && isVisible() && _fragmentFirstTimeVisible) {
+                    _fragmentFirstTimeVisible = false;
+                    onFragmentFirstTimeVisible();
+                }
+            }
+        }, 1);
+    }
+
+    /**
+     * Get a tag from the fragment, allows faster distinction
+     *
+     * @return This fragments tag
+     */
+    public abstract String getFragmentTag();
+
+
+    /**
+     * Get the layout to be inflated in the fragment
+     *
+     * @return Layout resource id
+     */
+    @LayoutRes
+    protected abstract int getLayoutResId();
+
+    /**
+     * Event to be called when the back button was pressed
+     * True should be returned when this was handled by the fragment
+     * and  no further handling in the view hierarchy is needed
+     *
+     * @return True if back handled by fragment
+     */
+    public boolean onBackPressed() {
+        return false;
+    }
+
+    /**
+     * Set the language to be used in this fragment
+     * Defaults to resolve the language from sharedpreferences: pref_key__language
+     *
+     * @return Empty string for system language, or an android locale code
+     */
+    public String getAppLanguage() {
+        if (getContext() != null) {
+            return getContext().getSharedPreferences("app", Context.MODE_PRIVATE)
+                    .getString("pref_key__language", "");
+        }
+        return "";
+    }
+
+    /**
+     * This will be called when this fragment gets the first time visible
+     */
+    public void onFragmentFirstTimeVisible() {
+    }
+
+    @Override
+    public void setUserVisibleHint(boolean isVisibleToUser) {
+        super.setUserVisibleHint(isVisibleToUser);
+        synchronized (_fragmentFirstTimeVisibleSync) {
+            if (isVisibleToUser && _fragmentFirstTimeVisible) {
+                _fragmentFirstTimeVisible = false;
+                onFragmentFirstTimeVisible();
+            }
+        }
+    }
+}