android - 找不到浏览器的提供商信息

Question

我正在使用 Coursera 的 MOOC，我正在尝试运行一个读取书签并显示它们的应用程序。

为此，我需要在 AndroidManifest 中设置权限:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="course.labs.permissionslab"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="18" />

    <uses-permission android:name="com.android.browser.permission.READ_HISTORY_BOOKMARKS"/>
    <!--  TODO - add uses-permission elements -->


    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".ActivityLoaderActivity"
            android:label="@string/title_main" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity
            android:name=".BookmarksActivity"
            android:label="@string/title_permissions" >
        </activity>
        <activity
            android:name=".GoToDangerousActivity"
            android:label="@string/title_activity_customization" >
        </activity>
    </application>

</manifest>

这可以防止出现 SecurityException，但是，当我尝试在我的 Android 设备上运行我的应用程序时，我在 LogCat 中收到以下错误:

03-02 02:58:13.579: I/Lab-Permissions(15438): Entered loadBookmarks()
03-02 02:58:13.589: W/dalvikvm(15438): threadid=1: thread exiting with uncaught exception (group=0x4166d498)
03-02 02:58:13.589: E/ActivityThread(15438): Failed to find provider info for browser
03-02 02:58:13.589: E/test(15438): Exception
03-02 02:58:13.609: E/AndroidRuntime(15438): FATAL EXCEPTION: main
03-02 02:58:13.609: E/AndroidRuntime(15438): java.lang.NullPointerException
03-02 02:58:13.609: E/AndroidRuntime(15438):    at course.labs.permissionslab.BookmarksActivity.loadBookmarks(BookmarksActivity.java:59)
03-02 02:58:13.609: E/AndroidRuntime(15438):    at course.labs.permissionslab.BookmarksActivity.access$0(BookmarksActivity.java:50)
03-02 02:58:13.609: E/AndroidRuntime(15438):    at course.labs.permissionslab.BookmarksActivity$1.onClick(BookmarksActivity.java:32)
03-02 02:58:13.609: E/AndroidRuntime(15438):    at android.view.View.performClick(View.java:4106)
03-02 02:58:13.609: E/AndroidRuntime(15438):    at android.view.View$PerformClick.run(View.java:17150)
03-02 02:58:13.609: E/AndroidRuntime(15438):    at android.os.Handler.handleCallback(Handler.java:615)
03-02 02:58:13.609: E/AndroidRuntime(15438):    at android.os.Handler.dispatchMessage(Handler.java:92)
03-02 02:58:13.609: E/AndroidRuntime(15438):    at android.os.Looper.loop(Looper.java:137)
03-02 02:58:13.609: E/AndroidRuntime(15438):    at android.app.ActivityThread.main(ActivityThread.java:4792)
03-02 02:58:13.609: E/AndroidRuntime(15438):    at java.lang.reflect.Method.invokeNative(Native Method)
03-02 02:58:13.609: E/AndroidRuntime(15438):    at java.lang.reflect.Method.invoke(Method.java:511)
03-02 02:58:13.609: E/AndroidRuntime(15438):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:808)
03-02 02:58:13.609: E/AndroidRuntime(15438):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:575)
03-02 02:58:13.609: E/AndroidRuntime(15438):    at dalvik.system.NativeStart.main(Native Method)

我不明白这是怎么回事，它似乎找不到提供商，但我有两个浏览器，所以我不明白。

这是我的 BookmarksActivy 代码，请忽略调用其他东西的“危险 Activity ”。

package course.labs.permissionslab;

import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.provider.Browser;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class BookmarksActivity extends Activity {

    private static final String TAG = "Lab-Permissions";

    static final String[] projection = { Browser.BookmarkColumns.TITLE,
            Browser.BookmarkColumns.URL };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.bookmarks_activity);

        Button getBookmarksButton = (Button) findViewById(R.id.get_bookmarks_button);
        getBookmarksButton.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {

                loadBookmarks();

            }
        });

        Button goToDangerousActivityButton = (Button) findViewById(R.id.go_to_dangerous_activity_button);
        goToDangerousActivityButton.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {

                startGoToDangerousActivity();

            }
        });

    }

    private void loadBookmarks() {

        Log.i(TAG, "Entered loadBookmarks()");

        String text = "";

        Cursor query = getContentResolver().query(Browser.BOOKMARKS_URI,
                projection, null, null, null);

        query.moveToFirst();
        while (query.moveToNext()) {

            text += query.getString(query
                    .getColumnIndex(Browser.BookmarkColumns.TITLE));
            text += "\n";
            text += query.getString(query
                    .getColumnIndex(Browser.BookmarkColumns.URL));
            text += "\n\n";

        }

        TextView box = (TextView) findViewById(R.id.text);
        box.setText(text);

        Log.i(TAG, "Bookmarks loaded");
    }

    private void startGoToDangerousActivity() {

        Log.i(TAG, "Entered startGoToDangerousActivity()");

        Intent dangerous = new Intent(BookmarksActivity.this,GoToDangerousActivity.class);
            startActivity(dangerous);
    }

}

Answer 1

您的设备可能运行 Chrome 而不是 AOSP 浏览器。如果是这样，请使用:

而不是 Browser.BOOKMARKS_URI

Uri.parse("content://com.android.chrome.browser/bookmarks")

即，

Cursor query = getContentResolver().query(Uri.parse("content://com.android.chrome.browser/bookmarks"),
                projection, null, null, null);