Add progress feedback while unzipping (Android).

README.md

@@ -9,11 +9,22 @@ A Cordova plugin to unzip files in Android and iOS.
 
 ##Usage
 
-    zip.unzip(<source zip>, <destination dir>, <callback>);
+    zip.unzip(<source zip>, <destination dir>, <callback>, [<progressCallback>]);
 
 Both source and destination arguments can be URLs obtained from the HTML File
 interface or absolute paths to files on the device.
 
 The callback argument will be executed when the unzip is complete, or when an
 error occurs. It will be called with a single argument, which will be 0 on
 success, or -1 on failure.
+
+The progressCallback argument is optional and will be executed whenever a new ZipEntry
+has been extracted. E.g.:
+
+    var progressCallback = function(progressEvent) {
+        $( "#progressbar" ).progressbar("value", Math.round((progressEvent.loaded / progressEvent.total) * 100));
+    };
+
+The values `loaded` and `total` are the number of compressed bytes processed and total. Total is the
+file size of the zip file.
+

src/android/Zip.java

@@ -13,7 +13,10 @@
 import android.net.Uri;
 import org.apache.cordova.CallbackContext;
 import org.apache.cordova.CordovaPlugin;
+import org.apache.cordova.CordovaResourceApi.OpenForReadResult;
+import org.apache.cordova.PluginResult;
 import org.json.JSONException;
+import org.json.JSONObject;
 
 import android.util.Log;
 
@@ -64,7 +67,11 @@ private void unzipSync(CordovaArgs args, CallbackContext callbackContext) {
                 throw new FileNotFoundException("File: \"" + outputDirectory + "\" not found");
             }
 
-            InputStream is = resourceApi.openForRead(zipUri).inputStream;
+            OpenForReadResult zipFile = resourceApi.openForRead(zipUri);
+            ProgressEvent progress = new ProgressEvent();
+            progress.setTotal(zipFile.length);
+
+            InputStream is = zipFile.inputStream;
 
             if (zipFileName.endsWith("crx")) {
                 // CRX files contain a header. This header consists of:
@@ -86,6 +93,8 @@ private void unzipSync(CordovaArgs args, CallbackContext callbackContext) {
                 is.skip(2);
 
                 is.skip(pubkeyLength + signatureLength);
+
+                progress.setLoaded(4 + 4 + 4 + 4 + pubkeyLength + signatureLength);
             }
 
             // The inputstream is now pointing at the start of the actual zip file content.
@@ -96,6 +105,8 @@ private void unzipSync(CordovaArgs args, CallbackContext callbackContext) {
             byte[] buffer = new byte[1024];
             boolean anyEntries = false;
 
+            updateProgress(callbackContext, progress);
+
             while ((ze = zis.getNextEntry()) != null) 
             {
                 anyEntries = true;
@@ -118,9 +129,16 @@ private void unzipSync(CordovaArgs args, CallbackContext callbackContext) {
                     }
 
                 }
+                progress.addLoaded(ze.getCompressedSize());
+                updateProgress(callbackContext, progress);
                 zis.closeEntry();
             }
             zis.close();
+
+            // final progress = 100%
+            progress.setLoaded(progress.getTotal());
+            updateProgress(callbackContext, progress);
+
             if (anyEntries)
                 callbackContext.success();
             else
@@ -132,10 +150,41 @@ private void unzipSync(CordovaArgs args, CallbackContext callbackContext) {
         }
     }
 
+    private void updateProgress(CallbackContext callbackContext, ProgressEvent progress) throws JSONException {
+        PluginResult pluginResult = new PluginResult(PluginResult.Status.OK, progress.toJSONObject());
+        pluginResult.setKeepCallback(true);
+        callbackContext.sendPluginResult(pluginResult);
+    }
+
     private Uri getUriForArg(String arg) {
         CordovaResourceApi resourceApi = webView.getResourceApi();
         Uri tmpTarget = Uri.parse(arg);
         return resourceApi.remapUri(
                 tmpTarget.getScheme() != null ? tmpTarget : Uri.fromFile(new File(arg)));
     }
+
+    private static class ProgressEvent {
+        private long loaded;
+        private long total;
+        public long getLoaded() {
+            return loaded;
+        }
+        public void setLoaded(long loaded) {
+            this.loaded = loaded;
+        }
+        public void addLoaded(long add) {
+            this.loaded += add;
+        }
+        public long getTotal() {
+            return total;
+        }
+        public void setTotal(long total) {
+            this.total = total;
+        }
+        public JSONObject toJSONObject() throws JSONException {
+            return new JSONObject(
+                    "{loaded:" + loaded +
+                    ",total:" + total + "}");
+        }
+    }
 }

zip.js

@@ -1,11 +1,27 @@
 var exec = cordova.require('cordova/exec');
 
-exports.unzip = function(fileName, outputDirectory, callback) {
-    var win = callback && function() {
-        callback(0);
+function newProgressEvent(result) {
+    var event = {
+            loaded: result.loaded,
+            total: result.total
     };
-    var fail = callback && function() {
-        callback(-1);
+    return event;
+}
+
+exports.unzip = function(fileName, outputDirectory, callback, progressCallback) {
+    var win = function(result) {
+        if (result && typeof result.loaded != "undefined") {
+            if (progressCallback) {
+                return progressCallback(newProgressEvent(result));
+            }
+        } else if (callback) {
+            callback(0);
+        }
+    };
+    var fail = function(result) {
+        if (callback) {
+            callback(-1);
+        }
     };
     exec(win, fail, 'Zip', 'unzip', [fileName, outputDirectory]);
 };