关于使用Intent协议在webview中跳转三方app

最近项目上有个需求，是关于在webview加载一个url的形式使用Intent协议跳转到指定的app页面，查看Intent源码发现Intent.parseUri()方法的第二个参数flag有三种类型： Intent.URI_ANDROID_APP_SCHEME 和 Intent.URI_INTENT_SCHEME 还有 URI_ALLOW_UNSAFE ；第三种不安全，一般不使用。 前俩种的格式为intent://host/#Intent;scheme=hansel;package=com.hansel.app;end 在#Intent之前可以带一些参数
android-app://{package_id}[/{scheme}[/{host}[/{path}]]][#Intent;{…}] 这个是第二种（PS:这种的scheme总是android-app）
在接收的app的manifest中的Activity注册这些信息

（intent://协议默认的是Action_View ; app-android 默认在格式中只指定了包名的话，actionMain ，如果有scheme和host则默认为actionView，当然如果协议中指定了action的话，就是你指定的action,下面是官方的截图）

接收的app注册这些信息，这里MainActivity 是接收intent:// 协议 Main2Activity接收android-app:// 协议。使用intent://时候一定要注册data的scheme 用来和发起请求的scheme匹配对应； 但是android-app则不太一样，可以不注册data的scheme,但是请求的时候要指定component即：”android-app://com.ebensz.appmanager/#Intent;component=com.ebensz.appmanager/com.ebensz.appmanager.MainActivity;end”; 而且android-app时候接收到的scheme 是android-app; intent://则是指定的scheme

发起请求的代码：在shouldoverride 加入判断 网上通用的方法

***纠正一处错误***
判断协议类型的时候,@纠错,此处的判断不应该为else if (url.startWith("intent")),这样的话不能响应自定义的协议头（大部分的app是使用自己定义的scheme头,把自定义的类型并入flag是URI_INTENT_SCHEME），现在贴下原因:
(太长了就放在最后了哈)
 Intent intent = null;
        // perform generic parsing of the URI to turn it into an Intent.
        try {
            if (url.startsWith("android-app://")){
                intent = Intent.parseUri(url,Intent.URI_ANDROID_APP_SCHEME);
            }else { // @纠错
                intent = Intent.parseUri(url, Intent.URI_INTENT_SCHEME);
            }
        } catch (URISyntaxException ex) {
            LogUtil.w("Browser", "Bad URI " + url + ": " + ex.getMessage());
            return false;
        }
        if (intent!=null && !TextUtils.isEmpty(intent.getScheme()) && BrowserUtils.isBlackScheme(intent.getScheme())) {
            return true;
        }

        // check whether the intent can be resolved. If not, we will see
        // whether we can download it from the Market.
        // 如果本地没装能响应特殊协议的应用则return
        if (getPackageManager().resolveActivity(intent, 0) == null) {

            return true;
        }

        // sanitize the Intent, ensuring web pages can not bypass browser
        // security (only access to BROWSABLE activities).
        intent.addCategory(Intent.CATEGORY_BROWSABLE);
        if (!url.startsWith("android-app://")) {
            intent.setComponent(null);
        }

        try {

            if (startActivityIfNeeded(intent, -1)) {
                LogUtil.d("tag","sucess use the intent ");

                return true;
            }


        } catch (ActivityNotFoundException ex) {
            LogUtil.d("tag","error message is --> " + ex.getMessage());
            // ignore the error. If no application can handle the URL,
            // eg about:blank, assume the browser can handle it.
        } catch (SecurityException se) {
            se.printStackTrace();
        }

附上android文档的解释

/**
* Flag for use with {@link #toUri} and {@link #parseUri}: the URI string
* always has the “intent:” scheme. This syntax can be used when you want
* to later disambiguate between URIs that are intended to describe an
* Intent vs. all others that should be treated as raw URIs. When used
* with {@link #parseUri}, any other scheme will result in a generic
* VIEW action for that raw URI.
*/
public static final int URI_INTENT_SCHEME = 1<<0;

/**
 * Flag for use with {@link #toUri} and {@link #parseUri}: the URI string
 * always has the "android-app:" scheme.  This is a variation of
 * {@link #URI_INTENT_SCHEME} whose format is simpler for the case of an
 * http/https URI being delivered to a specific package name.  The format
 * is:
 *
 * 
 * android-app://{package_id}[/{scheme}[/{host}[/{path}]]][#Intent;{...}]
 *
 * 
In this scheme, only the package_id is required.  If you include a host,
 * you must also include a scheme; including a path also requires both a host and a scheme.
 * The final #Intent; fragment can be used without a scheme, host, or path.
 * Note that this can not be
 * used with intents that have a {@link #setSelector}, since the base intent
 * will always have an explicit package name.
 *
 * 
Some examples of how this scheme maps to Intent objects:
 * 
 *     *     *     
 *     
 *     
 *
 *     
 *     
 *         
 *     
 *     
 *         
 *     
 *     
 *         
 *     
 *     
 *         
 *     
 *     
 *         
 *     
 *     
 *         
 *     
 *     
 * 

 
 
URI
 
Intent
android-app://com.example.app

 *             
 *             
 *         
Action: 
{@link #ACTION_MAIN}
Package: 
com.example.app
android-app://com.example.app/http/example.com

 *             
 *             
 *             
 *         
Action: 
{@link #ACTION_VIEW}
Data: 
http://example.com/
Package: 
com.example.app
android-app://com.example.app/http/example.com/foo?1234

 *             
 *             
 *             
 *         
Action: 
{@link #ACTION_VIEW}
Data: 
http://example.com/foo?1234
Package: 
com.example.app
android-app://com.example.app/
#Intent;action=com.example.MY_ACTION;end

 *             
 *             
 *         
Action: 
com.example.MY_ACTION
Package: 
com.example.app
android-app://com.example.app/http/example.com/foo?1234
#Intent;action=com.example.MY_ACTION;end

 *             
 *             
 *             
 *         
Action: 
com.example.MY_ACTION
Data: 
http://example.com/foo?1234
Package: 
com.example.app
android-app://com.example.app/
#Intent;action=com.example.MY_ACTION;
i.some_int=100;S.some_str=hello;end

 *             
 *             
 *             
 *         
Action: 
com.example.MY_ACTION
Package: 
com.example.app
Extras: 
some_int=(int)100
some_str=(String)hello
 */
public static final int URI_ANDROID_APP_SCHEME = 1<<1;

Intent.parseUri() 解读：

/**
     * Create an intent from a URI.  This URI may encode the action,
     * category, and other intent fields, if it was returned by
     * {@link #toUri}.  If the Intent was not generate by toUri(), its data
     * will be the entire URI and its action will be ACTION_VIEW.
     *
     * 
The URI given here must not be relative -- that is, it must include
     * the scheme and full path.
     *
     * @param uri The URI to turn into an Intent.
     * @param flags Additional processing flags.  Either 0,
     * {@link #URI_INTENT_SCHEME}, or {@link #URI_ANDROID_APP_SCHEME}.
     *
     * @return Intent The newly created Intent object.
     *
     * @throws URISyntaxException Throws URISyntaxError if the basic URI syntax
     * it bad (as parsed by the Uri class) or the Intent data within the
     * URI is invalid.
     *
     * @see #toUri
     */
    public static Intent parseUri(String uri, int flags) throws URISyntaxException {
        int i = 0;
        try {
            final boolean androidApp = uri.startsWith("android-app:");

 // flag传入URI_INTENT_SCHEME这个条件成立，生成的是自定义的scheme协议，非intent://和app-android://,所以上面把自定义的scheme加入URI_INTENT_SCHEME即可
            if ((flags&(URI_INTENT_SCHEME|URI_ANDROID_APP_SCHEME)) != 0) {
                if (!uri.startsWith("intent:") && !androidApp) {
                    Intent intent = new Intent(ACTION_VIEW);
                    try {
                        intent.setData(Uri.parse(uri));
                    } catch (IllegalArgumentException e) {
                        throw new URISyntaxException(uri, e.getMessage());
                    }
                    return intent;
                }
            }
            // 看下是否有#Intent后续的参数内容
            i = uri.lastIndexOf("#");
            // simple case
            if (i == -1) {
                if (!androidApp) {
                    return new Intent(ACTION_VIEW, Uri.parse(uri));
                }

            // old format Intent URI
            } else if (!uri.startsWith("#Intent;", i)) {
                if (!androidApp) {
                    return getIntentOld(uri, flags);
                } else {
                    i = -1;
                }
            }

            // new format
            Intent intent = new Intent(ACTION_VIEW);
            Intent baseIntent = intent;
            boolean explicitAction = false;// 指定action
            boolean inSelector = false;

            // fetch data part, if present
            String scheme = null;
            String data;
            if (i >= 0) {
                data = uri.substring(0, i);
                i += 8; // length of "#Intent;"
            } else {
                data = uri;
            }
            // 获取#Intent后面的附加属性
            // loop over contents of Intent, all name=value;
            while (i >= 0 && !uri.startsWith("end", i)) {
                int eq = uri.indexOf('=', i);
                if (eq < 0) eq = i-1;
                int semi = uri.indexOf(';', i);
                String value = eq < semi ? Uri.decode(uri.substring(eq + 1, semi)) : "";

                // action
                if (uri.startsWith("action=", i)) {
                    intent.setAction(value);
                    if (!inSelector) {
                        explicitAction = true;
                    }
                }

                // categories
                else if (uri.startsWith("category=", i)) {
                    intent.addCategory(value);
                }

                // type
                else if (uri.startsWith("type=", i)) {
                    intent.mType = value;
                }

                // launch flags
                else if (uri.startsWith("launchFlags=", i)) {
                    intent.mFlags = Integer.decode(value).intValue();
                    if ((flags& URI_ALLOW_UNSAFE) == 0) {
                        intent.mFlags &= ~IMMUTABLE_FLAGS;
                    }
                }

                // package
                else if (uri.startsWith("package=", i)) {
                    intent.mPackage = value;
                }

                // component
                else if (uri.startsWith("component=", i)) {
                    intent.mComponent = ComponentName.unflattenFromString(value);
                }

                // scheme
                else if (uri.startsWith("scheme=", i)) {
                    if (inSelector) {
                        intent.mData = Uri.parse(value + ":");
                    } else {
                        scheme = value;
                    }
                }

                // source bounds
                else if (uri.startsWith("sourceBounds=", i)) {
                    intent.mSourceBounds = Rect.unflattenFromString(value);
                }

                // selector
                else if (semi == (i+3) && uri.startsWith("SEL", i)) {
                    intent = new Intent();
                    inSelector = true;
                }

                // extra
                else {
                    String key = Uri.decode(uri.substring(i + 2, eq));
                    // create Bundle if it doesn't already exist
                    if (intent.mExtras == null) intent.mExtras = new Bundle();
                    Bundle b = intent.mExtras;
                    // add EXTRA
                    if      (uri.startsWith("S.", i)) b.putString(key, value);
                    else if (uri.startsWith("B.", i)) b.putBoolean(key, Boolean.parseBoolean(value));
                    else if (uri.startsWith("b.", i)) b.putByte(key, Byte.parseByte(value));
                    else if (uri.startsWith("c.", i)) b.putChar(key, value.charAt(0));
                    else if (uri.startsWith("d.", i)) b.putDouble(key, Double.parseDouble(value));
                    else if (uri.startsWith("f.", i)) b.putFloat(key, Float.parseFloat(value));
                    else if (uri.startsWith("i.", i)) b.putInt(key, Integer.parseInt(value));
                    else if (uri.startsWith("l.", i)) b.putLong(key, Long.parseLong(value));
                    else if (uri.startsWith("s.", i)) b.putShort(key, Short.parseShort(value));
                    else throw new URISyntaxException(uri, "unknown EXTRA type", i);
                }

                // move to the next item
                i = semi + 1;
            }

            if (inSelector) {
                // The Intent had a selector; fix it up.
                if (baseIntent.mPackage == null) {
                    baseIntent.setSelector(intent);
                }
                intent = baseIntent;
            }

            if (data != null) {
                if (data.startsWith("intent:")) {
                    data = data.substring(7);
                    if (scheme != null) {
                        data = scheme + ':' + data;
                    }
                } else if (data.startsWith("android-app:")) {
                    if (data.charAt(12) == '/' && data.charAt(13) == '/') {
                        // Correctly formed android-app, first part is package name.
                        int end = data.indexOf('/', 14);
                        if (end < 0) {
                            // All we have is a package name.
                            intent.mPackage = data.substring(14);
                            if (!explicitAction) {//没有action属性的时候“app-android”使用默认action_main
                                intent.setAction(ACTION_MAIN);
                            }
                            data = "";
                        } else {
                            // Target the Intent at the given package name always.
                            String authority = null;
                            intent.mPackage = data.substring(14, end);
                            int newEnd;
                            if ((end+1) < data.length()) {
                                if ((newEnd=data.indexOf('/', end+1)) >= 0) {
                                    // Found a scheme, remember it.
                                    scheme = data.substring(end+1, newEnd);
                                    end = newEnd;
                                    if (end < data.length() && (newEnd=data.indexOf('/', end+1)) >= 0) {
                                        // Found a authority, remember it.
                                        authority = data.substring(end+1, newEnd);
                                        end = newEnd;
                                    }
                                } else {
                                    // All we have is a scheme.
                                    scheme = data.substring(end+1);
                                }
                            }
                            if (scheme == null) {
                                // If there was no scheme, then this just targets the package.
                                if (!explicitAction) {
                                    intent.setAction(ACTION_MAIN);
                                }
                                data = "";
                            } else if (authority == null) {
                                data = scheme + ":";
                            } else {
                                data = scheme + "://" + authority + data.substring(end);
                            }
                        }
                    } else {
                        data = "";
                    }
                }

                if (data.length() > 0) {
                    try {
                        intent.mData = Uri.parse(data);
                    } catch (IllegalArgumentException e) {
                        throw new URISyntaxException(uri, e.getMessage());
                    }
                }
            }

            return intent;

        } catch (IndexOutOfBoundsException e) {
            throw new URISyntaxException(uri, "illegal Intent URI format", i);
        }
    }