Only show preview context menu on supported file type. (#1908)

appinventor/appengine/src/com/google/appinventor/client/explorer/commands/ChainableCommand.java

@@ -157,6 +157,15 @@ public abstract class ChainableCommand {
    */
   protected abstract void execute(ProjectNode node);
 
+  /**
+   * Check if the command can be used for the project node.
+   * @param node the project node to which the command is applied
+   * @return
+   */
+  protected boolean isSupported(ProjectNode node) {
+    return true;
+  }
+
   /**
    * Executes the next command in the chain.
    *

appinventor/appengine/src/com/google/appinventor/client/explorer/commands/PreviewFileCommand.java

@@ -36,6 +36,12 @@ public class PreviewFileCommand extends ChainableCommand {
     return false;
   }
 
+  @Override
+  public boolean isSupported(final ProjectNode node) {
+    return StorageUtil.isImageFile(node.getFileId()) || StorageUtil.isAudioFile(node.getFileId())
+        || StorageUtil.isVideoFile(node.getFileId());
+  }
+
   @Override
   public void execute(final ProjectNode node) {
     final DialogBox dialogBox = new DialogBox();
@@ -95,7 +101,7 @@ public class PreviewFileCommand extends ChainableCommand {
       String fileType = StorageUtil.getContentTypeForFilePath(fileSuffix);
       // Support preview for file types that all major browser support
       if (fileType.endsWith("png") || fileType.endsWith("jpeg") || fileType.endsWith("gif")
-          || fileType.endsWith("bmp")) {
+          || fileType.endsWith("bmp") || fileType.endsWith("svg+xml")) {
         Image img = new Image(fileUrl);
         img.getElement().getStyle().setProperty("maxWidth","600px");
         return img;
@@ -108,7 +114,7 @@ public class PreviewFileCommand extends ChainableCommand {
       }
     } else if (StorageUtil.isVideoFile(fileSuffix)) { // Video Preview
       String fileType = StorageUtil.getContentTypeForFilePath(fileSuffix);
-      if (fileType.endsWith("mp4") || fileType.endsWith("webm")) {
+      if (fileType.endsWith("avi") || fileType.endsWith("mp4") || fileType.endsWith("webm")) {
         return new HTML("<video width='320' height='240' controls> <source src='" + fileUrl
             + "' type='" + fileType + "'>" + MESSAGES.filePlaybackError() + "</video>");
       }

appinventor/appengine/src/com/google/appinventor/client/explorer/commands/ProjectNodeCommand.java

@@ -53,4 +53,8 @@ public final class ProjectNodeCommand {
   public void execute(ProjectNode node) {
     command.startExecuteChain(actionName, node);
   }
+
+  public boolean isSupported(ProjectNode node) {
+    return command.isSupported(node);
+  }
 }

appinventor/appengine/src/com/google/appinventor/client/explorer/project/ProjectNodeContextMenu.java

@@ -45,7 +45,7 @@ public final class ProjectNodeContextMenu {
         Window.getScrollTop() + clientY);
     for (final CommandRegistry.Entry entry : entries) {
       final ProjectNodeCommand cmd = entry.getCommand();
-
+      if (cmd.isSupported(node)) {
         // Create the menu item.
         menu.addItem(cmd.getLabel(), new Command() {
           @Override
@@ -55,6 +55,7 @@ public final class ProjectNodeContextMenu {
           }
         });
       }
+    }
 
     menu.show();
   }

appinventor/appengine/src/com/google/appinventor/shared/storage/StorageUtil.java

@@ -124,6 +124,9 @@ public class StorageUtil {
     if (filePath.endsWith(".webp")) {
       return "image/webp";
     }
+    if (filePath.endsWith(".svg")) {
+      return "image/svg+xml";
+    }
 
     // Audio File Types
     if (filePath.endsWith(".mp3")) {
@@ -161,6 +164,9 @@ public class StorageUtil {
     }
 
     // Video File Types
+    if (filePath.endsWith(".avi")) {
+      return "video/avi";
+    }
     if (filePath.endsWith(".mp4")) {
       return "video/mp4";
     }
@@ -176,9 +182,6 @@ public class StorageUtil {
     if (filePath.endsWith(".mkv")) {
       return "video/mkv";
     }
-    if (filePath.endsWith(".svg")) {
-      return "image/svg+xml";
-    }
 
     // Other File Types
     if (filePath.endsWith(".apk")) {