Settings: Improved UX when viewing open source license info.

Added spinning progress indicator to the open source license dialog.
The actual file loading is now handled by a separate thread, in
order to provide user feedback and reduce risk for ANR.

Change-Id: Ia12727ecc2fe8114e0d1384769b568142c8a1db6

1 files changed, 145 insertions, 48 deletions

diff --git a/src/com/android/settings/SettingsLicenseActivity.java b/src/com/android/settings/SettingsLicenseActivity.java
index 0b809e1..99828ce 100644
--- a/src/com/android/settings/SettingsLicenseActivity.java
+++ b/src/com/android/settings/SettingsLicenseActivity.java
@@ -17,6 +17,8 @@
 package com.android.settings;
 
 import android.os.Bundle;
+import android.os.Handler;
+import android.os.Message;
 import android.os.SystemProperties;
 import android.text.TextUtils;
 import android.util.Config;
@@ -24,6 +26,12 @@ import android.util.Log;
 import android.webkit.WebView;
 import android.webkit.WebViewClient;
 import android.widget.Toast;
+import android.app.Activity;
+import android.app.AlertDialog;
+import android.app.ProgressDialog;
+import android.content.DialogInterface;
+import android.content.DialogInterface.OnDismissListener;
+import android.content.res.Configuration;
 
 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
@@ -32,13 +40,10 @@ import java.io.IOException;
 import java.io.InputStreamReader;
 import java.util.zip.GZIPInputStream;
 
-import com.android.internal.app.AlertActivity;
-import com.android.internal.app.AlertController;
-
 /**
  * The "dialog" that shows from "License" in the Settings app.
  */
-public class SettingsLicenseActivity extends AlertActivity {
+public class SettingsLicenseActivity extends Activity {
 
     private static final String TAG = "SettingsLicenseActivity";
     private static final boolean LOGV = false || Config.LOGV;
@@ -46,6 +51,83 @@ public class SettingsLicenseActivity extends AlertActivity {
     private static final String DEFAULT_LICENSE_PATH = "/system/etc/NOTICE.html.gz";
     private static final String PROPERTY_LICENSE_PATH = "ro.config.license_path";
 
+    private Handler mHandler;
+    private WebView mWebView;
+    private ProgressDialog mSpinnerDlg;
+    private AlertDialog mTextDlg;
+
+    private class LicenseFileLoader implements Runnable {
+
+        private static final String INNER_TAG = "SettingsLicenseActivity.LicenseFileLoader";
+        public static final int STATUS_OK = 0;
+        public static final int STATUS_NOT_FOUND = 1;
+        public static final int STATUS_READ_ERROR = 2;
+        public static final int STATUS_EMPTY_FILE = 3;
+
+        private String mFileName;
+        private Handler mHandler;
+
+        public LicenseFileLoader(String fileName, Handler handler) {
+            mFileName = fileName;
+            mHandler = handler;
+        }
+
+        public void run() {
+
+            int status = STATUS_OK;
+
+            InputStreamReader inputReader = null;
+            StringBuilder data = new StringBuilder(2048);
+            try {
+                char[] tmp = new char[2048];
+                int numRead;
+                if (mFileName.endsWith(".gz")) {
+                    inputReader = new InputStreamReader(
+                        new GZIPInputStream(new FileInputStream(mFileName)));
+                } else {
+                    inputReader = new FileReader(mFileName);
+                }
+
+                while ((numRead = inputReader.read(tmp)) >= 0) {
+                    data.append(tmp, 0, numRead);
+                }
+            } catch (FileNotFoundException e) {
+                Log.e(INNER_TAG, "License HTML file not found at " + mFileName, e);
+                status = STATUS_NOT_FOUND;
+            } catch (IOException e) {
+                Log.e(INNER_TAG, "Error reading license HTML file at " + mFileName, e);
+                status = STATUS_READ_ERROR;
+            } finally {
+                try {
+                    if (inputReader != null) {
+                        inputReader.close();
+                    }
+                } catch (IOException e) {
+                }
+            }
+
+            if ((status == STATUS_OK) && TextUtils.isEmpty(data)) {
+                Log.e(INNER_TAG, "License HTML is empty (from " + mFileName + ")");
+                status = STATUS_EMPTY_FILE;
+            }
+
+            // Tell the UI thread that we are finished.
+            Message msg = mHandler.obtainMessage(status, null);
+            if (status == STATUS_OK) {
+                msg.obj = data.toString();
+            }
+            mHandler.sendMessage(msg);
+        }
+    }
+
+    public SettingsLicenseActivity() {
+        super();
+        mHandler = null;
+        mWebView = null;
+        mSpinnerDlg = null;
+        mTextDlg = null;
+    }
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -57,67 +139,82 @@ public class SettingsLicenseActivity extends AlertActivity {
             return;
         }
 
-        InputStreamReader inputReader = null;
-        StringBuilder data = null;
-        try {
-            data = new StringBuilder(2048);
-            char tmp[] = new char[2048];
-            int numRead;
-            if (fileName.endsWith(".gz")) {
-                inputReader = new InputStreamReader(
-                    new GZIPInputStream(new FileInputStream(fileName)));
-            } else {
-                inputReader = new FileReader(fileName);
-            }
-            while ((numRead = inputReader.read(tmp)) >= 0) {
-                data.append(tmp, 0, numRead);
-            }
-        } catch (FileNotFoundException e) {
-            Log.e(TAG, "License HTML file not found at " + fileName, e);
-            showErrorAndFinish();
-            return;
-        } catch (IOException e) {
-            Log.e(TAG, "Error reading license HTML file at " + fileName, e);
-            showErrorAndFinish();
-            return;
-        } finally {
-            try {
-                if (inputReader != null) {
-                    inputReader.close();
+        // The activity does not have any view itself,
+        // so set it invisible to avoid displaying the title text in the background.
+        setVisible(false);
+
+        mWebView = new WebView(this);
+
+        mHandler = new Handler() {
+
+            @Override
+            public void handleMessage(Message msg) {
+                super.handleMessage(msg);
+
+                if (msg.what == LicenseFileLoader.STATUS_OK) {
+                    String text = (String) msg.obj;
+                    showPageOfText(text);
+                } else {
+                    showErrorAndFinish();
                 }
-            } catch (IOException e) {
             }
-        }
+        };
 
-        if (TextUtils.isEmpty(data)) {
-            Log.e(TAG, "License HTML is empty (from " + fileName + ")");
-            showErrorAndFinish();
-            return;
+        CharSequence title = getText(R.string.settings_license_activity_title);
+        CharSequence msg = getText(R.string.settings_license_activity_loading);
+
+        ProgressDialog pd = ProgressDialog.show(this, title, msg, true, false);
+        pd.setProgressStyle(ProgressDialog.STYLE_SPINNER);
+        mSpinnerDlg = pd;
+
+        // Start separate thread to do the actual loading.
+        Thread thread = new Thread(new LicenseFileLoader(fileName, mHandler));
+        thread.start();
+    }
+
+    @Override
+    protected void onDestroy() {
+        super.onDestroy();
+        if (mTextDlg != null) {
+            mTextDlg.dismiss();
         }
+    }
+
+    private void showPageOfText(String text) {
+        // Create an AlertDialog to display the WebView in.
+        AlertDialog.Builder builder = new AlertDialog.Builder(SettingsLicenseActivity.this);
+        builder.setCancelable(true)
+               .setView(mWebView)
+               .setTitle(R.string.settings_license_activity_title);
+
+        mTextDlg = builder.create();
+        mTextDlg.setOnDismissListener(new OnDismissListener() {
 
-        WebView webView = new WebView(this);
+            public void onDismiss(DialogInterface dlgi) {
+                SettingsLicenseActivity.this.finish();
+            }
+        });
 
         // Begin the loading.  This will be done in a separate thread in WebView.
-        webView.loadDataWithBaseURL(null, data.toString(), "text/html", "utf-8", null);
-        webView.setWebViewClient(new WebViewClient() {
+        mWebView.loadDataWithBaseURL(null, text, "text/html", "utf-8", null);
+        mWebView.setWebViewClient(new WebViewClient() {
             @Override
             public void onPageFinished(WebView view, String url) {
-                // Change from 'Loading...' to the real title
-                mAlert.setTitle(getString(R.string.settings_license_activity_title));
+                mSpinnerDlg.dismiss();
+                mSpinnerDlg = null;
+                mTextDlg.show();
+                mTextDlg = null;
             }
         });
 
-        final AlertController.AlertParams p = mAlertParams;
-        p.mTitle = getString(R.string.settings_license_activity_loading);
-        p.mView = webView;
-        p.mForceInverseBackground = true;
-        setupAlert();
+        mWebView = null;
     }
 
     private void showErrorAndFinish() {
+        mSpinnerDlg.dismiss();
+        mSpinnerDlg = null;
         Toast.makeText(this, R.string.settings_license_activity_unavailable, Toast.LENGTH_LONG)
                 .show();
         finish();
     }
-
 }