refactor: replace Animation interface with Animatable interface

- Replaced `Animation` interface with `Animatable` interface
- Changed `onStartShowAnimation` and `onStartHideAnimation` methods to `toggleViewsAnimation` method

Closes #34

Author: DylanCaiCoding

loadingstateview-ktx/src/main/java/com/dylanc/loadingstateview/LoadingState.kt

@@ -52,15 +52,15 @@ interface LoadingState : Decorative, OnReloadListener {
 
   fun Fragment.setDecorView(delegate: LoadingStateView.DecorViewDelegate)
 
-  fun showLoadingView(animation: LoadingStateView.Animation? = null)
+  fun showLoadingView(animatable: LoadingStateView.Animatable? = LoadingStateView.defaultAnimatable)
 
-  fun showContentView(animation: LoadingStateView.Animation? = null)
+  fun showContentView(animatable: LoadingStateView.Animatable? = LoadingStateView.defaultAnimatable)
 
-  fun showErrorView(animation: LoadingStateView.Animation? = null)
+  fun showErrorView(animatable: LoadingStateView.Animatable? = LoadingStateView.defaultAnimatable)
 
-  fun showEmptyView(animation: LoadingStateView.Animation? = null)
+  fun showEmptyView(animatable: LoadingStateView.Animatable? = LoadingStateView.defaultAnimatable)
 
-  fun showCustomView(viewType: Any)
+  fun showCustomView(viewType: Any, animatable: LoadingStateView.Animatable? = LoadingStateView.defaultAnimatable)
 
   fun updateToolbar(block: ToolbarConfig.() -> Unit)
 

loadingstateview-ktx/src/main/java/com/dylanc/loadingstateview/LoadingStateDelegate.kt

@@ -37,6 +37,7 @@ class LoadingStateDelegate : LoadingState {
       !decorative.isDecorated -> this
       decorative.contentView == null ->
         LoadingStateView(this, decorative).also { loadingStateView = it }.decorView
+
       else -> {
         loadingStateView = LoadingStateView(decorative.contentView!!, decorative)
         this
@@ -79,24 +80,24 @@ class LoadingStateDelegate : LoadingState {
     loadingStateView?.addChildDecorView(delegate)
   }
 
-  override fun showLoadingView(animation: LoadingStateView.Animation?) {
-    loadingStateView?.showLoadingView(animation)
+  override fun showLoadingView(animatable: LoadingStateView.Animatable?) {
+    loadingStateView?.showLoadingView(animatable)
   }
 
-  override fun showContentView(animation: LoadingStateView.Animation?) {
-    loadingStateView?.showContentView(animation)
+  override fun showContentView(animatable: LoadingStateView.Animatable?) {
+    loadingStateView?.showContentView(animatable)
   }
 
-  override fun showErrorView(animation: LoadingStateView.Animation?) {
-    loadingStateView?.showErrorView(animation)
+  override fun showErrorView(animatable: LoadingStateView.Animatable?) {
+    loadingStateView?.showErrorView(animatable)
   }
 
-  override fun showEmptyView(animation: LoadingStateView.Animation?) {
-    loadingStateView?.showEmptyView(animation)
+  override fun showEmptyView(animatable: LoadingStateView.Animatable?) {
+    loadingStateView?.showEmptyView(animatable)
   }
 
-  override fun showCustomView(viewType: Any) {
-    loadingStateView?.showView(viewType)
+  override fun showCustomView(viewType: Any, animatable: LoadingStateView.Animatable?) {
+    loadingStateView?.showView(viewType, animatable)
   }
 
   override fun updateToolbar(block: ToolbarConfig.() -> Unit) {

loadingstateview/src/main/java/com/dylanc/loadingstateview/LoadingStateView.kt

@@ -39,7 +39,7 @@ class LoadingStateView @JvmOverloads constructor(
   private val parent: ViewGroup?
   private var currentView: View? = null
   private var viewDelegates: HashMap<Any, ViewDelegate> = HashMap()
-  private val viewCashes: HashMap<Any, View> = HashMap()
+  private val viewCaches: HashMap<Any, View> = HashMap()
 
   /**
    * Constructs a LoadingStateView with an activity and listener.
@@ -123,41 +123,41 @@ class LoadingStateView @JvmOverloads constructor(
   fun register(vararg delegates: ViewDelegate) = delegates.forEach { viewDelegates[it.viewType] = it }
 
   @JvmOverloads
-  fun showLoadingView(animation: Animation? = null) = showView(ViewType.LOADING, animation)
+  fun showLoadingView(animatable: Animatable? = defaultAnimatable) = showView(ViewType.LOADING, animatable)
 
   @JvmOverloads
-  fun showContentView(animation: Animation? = null) = showView(ViewType.CONTENT, animation)
+  fun showContentView(animatable: Animatable? = defaultAnimatable) = showView(ViewType.CONTENT, animatable)
 
   @JvmOverloads
-  fun showErrorView(animation: Animation? = null) = showView(ViewType.ERROR, animation)
+  fun showErrorView(animatable: Animatable? = defaultAnimatable) = showView(ViewType.ERROR, animatable)
 
   @JvmOverloads
-  fun showEmptyView(animation: Animation? = null) = showView(ViewType.EMPTY, animation)
+  fun showEmptyView(animatable: Animatable? = defaultAnimatable) = showView(ViewType.EMPTY, animatable)
 
   /**
    * Shows the view by view type
    *
    * @param viewType the view type of view delegate
    */
   @JvmOverloads
-  fun showView(viewType: Any, animation: Animation? = null) {
+  fun showView(viewType: Any, animatable: Animatable? = defaultAnimatable) {
     val currentView = currentView
     if (currentView == null) {
       addView(viewType)
     } else {
-      if (viewCashes[viewType] == null) addView(viewType)
+      if (viewCaches[viewType] == null) addView(viewType)
       if (viewType != currentViewType) {
-        val view = getView(viewType)
-        view.visibility = View.VISIBLE
-        getViewDelegate<ViewDelegate>(viewType)?.onViewAttached(view)
-        if (animation != null) {
-          animation.onStartHideAnimation(currentView, currentViewType)
-          animation.onStartShowAnimation(view, getViewDelegate<ViewDelegate>(viewType)!!.viewType)
+        val nextView = getOrCreateView(viewType)
+        nextView.visibility = View.VISIBLE
+        val nextViewDelegate = getViewDelegate<ViewDelegate>(viewType)
+        nextViewDelegate?.onViewAttached(nextView)
+        getViewDelegate<ViewDelegate>(currentViewType)?.onViewDetached(nextView)
+        if (animatable != null && nextViewDelegate != null) {
+          animatable.toggleViewsAnimation(nextView, currentView, viewType, currentViewType)
         } else {
           currentView.visibility = View.GONE
         }
-        getViewDelegate<ViewDelegate>(currentViewType)?.onViewDetached(view)
-        this.currentView = view
+        this.currentView = nextView
       }
     }
     currentViewType = viewType
@@ -170,7 +170,7 @@ class LoadingStateView @JvmOverloads constructor(
   fun <T : ViewDelegate> getViewDelegate(viewType: Any) = viewDelegates[viewType] as? T
 
   private fun addView(viewType: Any) {
-    val view = getView(viewType)
+    val view = getOrCreateView(viewType)
     (view.parent as? ViewGroup)?.removeView(view)
     if (parent is ConstraintLayout && viewType == ViewType.CONTENT) {
       val params = view.layoutParams
@@ -182,14 +182,14 @@ class LoadingStateView @JvmOverloads constructor(
     currentView = view
   }
 
-  private fun getView(viewType: Any): View {
-    if (viewCashes[viewType] == null) {
+  private fun getOrCreateView(viewType: Any): View {
+    if (viewCaches[viewType] == null) {
       val viewDelegate = requireNotNull(getViewDelegate(viewType)) { "Please register view delegate for $viewType type." }
       val view = viewDelegate.onCreateView(LayoutInflater.from(contentParent.context), contentParent)
       viewDelegate.onReloadListener = onReloadListener
-      viewCashes[viewType] = view
+      viewCaches[viewType] = view
     }
-    return viewCashes[viewType]!!
+    return viewCaches[viewType]!!
   }
 
   abstract class ViewDelegate(val viewType: Any) {
@@ -214,7 +214,7 @@ class LoadingStateView @JvmOverloads constructor(
 
     constructor(delegates: Array<out ViewDelegate>) : this(delegates.map {
       register(it)
-      getView(it.viewType)
+      getOrCreateView(it.viewType)
     })
 
     override fun onCreateDecorView(context: Context, inflater: LayoutInflater) =
@@ -237,14 +237,16 @@ class LoadingStateView @JvmOverloads constructor(
     fun T.invoke()
   }
 
-  interface Animation {
-    fun onStartShowAnimation(view: View, viewType: Any)
-    fun onStartHideAnimation(view: View, viewType: Any)
+  interface Animatable {
+    fun toggleViewsAnimation(showView: View, hideView: View, showViewType: Any, hideViewType: Any)
   }
 
   companion object {
     private var poolInitializer: Callback<PoolInitializer>? = null
 
+    @JvmStatic
+    var defaultAnimatable: Animatable? = null
+
     @JvmStatic
     fun setViewDelegatePool(poolInitializer: Callback<PoolInitializer>) {
       this.poolInitializer = poolInitializer

sample-java/src/main/java/com/dylanc/loadingstateview/sample/java/App.java

@@ -19,6 +19,7 @@
 import android.app.Application;
 
 import com.dylanc.loadingstateview.LoadingStateView;
+import com.dylanc.loadingstateview.sample.java.animation.FadeAnimatable;
 import com.dylanc.loadingstateview.sample.java.delegate.EmptyViewDelegate;
 import com.dylanc.loadingstateview.sample.java.delegate.ErrorViewDelegate;
 import com.dylanc.loadingstateview.sample.java.delegate.LoadingViewDelegate;
@@ -32,5 +33,6 @@ public void onCreate() {
     super.onCreate();
     LoadingStateView.setViewDelegatePool(pool ->
         pool.register(new LoadingViewDelegate(), new ErrorViewDelegate(), new EmptyViewDelegate()));
+    LoadingStateView.setDefaultAnimatable(new FadeAnimatable());
   }
 }

sample-java/src/main/java/com/dylanc/loadingstateview/sample/java/animation/FadeAnimatable.java

@@ -0,0 +1,43 @@
+package com.dylanc.loadingstateview.sample.java.animation;
+
+import android.view.View;
+
+import androidx.annotation.NonNull;
+
+import com.dylanc.loadingstateview.LoadingStateView;
+import com.dylanc.loadingstateview.ViewType;
+
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * @author Dylan Cai
+ */
+public class FadeAnimatable implements LoadingStateView.Animatable {
+
+  private static final long DEFAULT_DURATION = 500;
+  private final long duration;
+
+  public FadeAnimatable() {
+    this(DEFAULT_DURATION);
+  }
+
+  public FadeAnimatable(long duration) {
+    this.duration = duration;
+  }
+
+  @Override
+  public void toggleViewsAnimation(@NonNull View showView, @NonNull View hideView, @NonNull Object showViewType, @NonNull Object hideViewType) {
+    showView.setAlpha(0);
+    showView.setVisibility(View.VISIBLE);
+    showView.animate().alpha(1).setDuration(duration);
+
+    if (showViewType == ViewType.LOADING && hideViewType == ViewType.CONTENT) {
+      hideView.setVisibility(View.GONE);
+    } else {
+      hideView.animate().alpha(0).setDuration(duration).withEndAction(() -> {
+        hideView.setAlpha(1);
+        hideView.setVisibility(View.GONE);
+      });
+    }
+  }
+}

sample-java/src/main/java/com/dylanc/loadingstateview/sample/java/animation/FadeAnimation.java

@@ -25,7 +25,6 @@
 import com.dylanc.loadingstateview.OnReloadListener;
 import com.dylanc.loadingstateview.sample.java.R;
 import com.dylanc.loadingstateview.sample.java.delegate.NavIconType;
-import com.dylanc.loadingstateview.sample.java.animation.FadeAnimation;
 import com.dylanc.loadingstateview.sample.java.utils.HttpUtils;
 import com.dylanc.loadingstateview.sample.java.utils.ToolbarUtils;
 
@@ -50,28 +49,28 @@ private void loadData() {
     HttpUtils.requestFailure(new HttpUtils.Callback() {
       @Override
       public void onSuccess() {
-        loadingStateView.showContentView(new FadeAnimation());
+        loadingStateView.showContentView();
       }
 
       @Override
       public void onFailure() {
-        loadingStateView.showErrorView(new FadeAnimation());
+        loadingStateView.showErrorView();
       }
     });
   }
 
   @Override
   public void onReload() {
-    loadingStateView.showLoadingView(new FadeAnimation());
+    loadingStateView.showLoadingView();
     HttpUtils.requestSuccess(new HttpUtils.Callback() {
       @Override
       public void onSuccess() {
-        loadingStateView.showContentView(new FadeAnimation());
+        loadingStateView.showContentView();
       }
 
       @Override
       public void onFailure() {
-        loadingStateView.showErrorView(new FadeAnimation());
+        loadingStateView.showErrorView();
       }
     });
   }

sample-java/src/main/java/com/dylanc/loadingstateview/sample/java/ui/ActErrorActivity.java

@@ -6,6 +6,7 @@ import com.dylanc.loadingstateview.sample.kotlin.delegate.ErrorViewDelegate
 import com.dylanc.loadingstateview.sample.kotlin.delegate.LoadingViewDelegate
 import com.dylanc.loadingstateview.sample.kotlin.delegate.ToolbarViewDelegate
 import com.dylanc.loadingstateview.sample.kotlin.delegate.EmptyViewDelegate
+import com.dylanc.loadingstateview.sample.kotlin.delegate.FadeAnimatable
 
 class App : Application() {
 
@@ -14,5 +15,6 @@ class App : Application() {
     LoadingStateView.setViewDelegatePool {
       register(ToolbarViewDelegate(), LoadingViewDelegate(), ErrorViewDelegate(), EmptyViewDelegate())
     }
+    LoadingStateView.defaultAnimatable = FadeAnimatable()
   }
 }

sample-kotlin/src/main/java/com/dylanc/loadingstateview/sample/kotlin/App.kt

@@ -0,0 +1,31 @@
+package com.dylanc.loadingstateview.sample.kotlin.delegate
+
+import android.view.View
+import com.dylanc.loadingstateview.LoadingStateView
+import com.dylanc.loadingstateview.ViewType
+
+/**
+ * @author Dylan Cai
+ */
+class FadeAnimatable @JvmOverloads constructor(
+  private val duration: Long = DEFAULT_DURATION
+) : LoadingStateView.Animatable {
+  override fun toggleViewsAnimation(showView: View, hideView: View, showViewType: Any, hideViewType: Any) {
+    showView.alpha = 0f
+    showView.visibility = View.VISIBLE
+    showView.animate().alpha(1f).setDuration(duration)
+
+    if (showViewType === ViewType.LOADING && hideViewType === ViewType.CONTENT) {
+      hideView.visibility = View.GONE
+    } else {
+      hideView.animate().alpha(0f).setDuration(duration).withEndAction {
+        hideView.alpha = 1f
+        hideView.visibility = View.GONE
+      }
+    }
+  }
+
+  companion object {
+    private const val DEFAULT_DURATION: Long = 600
+  }
+}

sample-kotlin/src/main/java/com/dylanc/loadingstateview/sample/kotlin/delegate/FadeAnimatable.kt

@@ -33,7 +33,10 @@ class MainActivity : BaseBindingActivity<ActivityMainBinding>() {
       rightTextColor = Color.BLUE
       rightText("Edit") { onEdit() }
     }
-    showErrorView()
+    showLoadingView()
+    Handler(Looper.getMainLooper()).postDelayed({
+      showErrorView()
+    }, 2000)
   }
 
   private fun onEdit() {