Android Html 與客戶端交互 ---- 1.）html 操做activity

1.何爲 scheme和Uri

在Android中scheme是指Uri連接 :以前的部分如 test://login scheme 即爲test。 可能不少人要爲URI是怎麼定義的呢？具體看URI的定義

---

• 英文願意： An identifier is an object that can act as a reference to something that has identity. In the case of URI, the object is a sequence of characters with a restricted syntax.
• 翻譯：一個具備參考對象的能夠惟一識別的標識符。在這種狀況下，這個對象在有限的語法表達出有序的符號

---

2.Uri 的結構

test://video：8080/event?title="scheme"&url="www.xiaomi.com"

1. scheme :test
2. host ：video
3. port：8080
4. path ：/event
5. query : titile ,url

3. 若是經過H5(url) 來啓動相應的頁面（activity）

String url="test://video：8080/event?title="scheme"&url="www.xiaomi.com" "
Intent intent=new Intent(Intent.ACTION_VIEW,Uri.parse(url));
startActivity(intent);

<activity android:name=".UriActivity">
           <intent-filter >
               <action android:name="android.intent.action.VIEW" />
               <category android:name="android.intent.category.DEFAULT" />
               <category android:name="android.intent.category.BROWSABLE" />
               <data android:scheme="test" android:host="video" />
           </intent-filter>
 </activity>

這樣就能夠在UriActivity 中接收url 跳轉相應的動做以及數據。

>  Uri data=getIntent().getData();
>      data.getScheme();
>      data.getHost();
>      data.getPort();
>      data.getPath();
>       data.getQueryParameter("title");

4.大量的不一樣的scheme跳轉

若是咱們在每一個activity 中配置scheme ，host，path 顯得特別麻煩。這個時候咱們須要一箇中轉的activity來處理全部的scheme的跳轉。根據相應的host，path 來跳轉到相應的activity作進一步處理。

protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       Intent intent = getIntent();
       Uri data = intent.getData();
       String host = data.getHost();
       if(host.equals("list")){
          if ("/near".equals(data.getPath())) {//yhouse://list/near 
                intentTransfer = new Intent(this, NearbyActivity.class);
            } else if ("/new".equals(data.getPath())) {//yhouse://list/new 
                intentTransfer = new Intent(this, NewSkuActivity.class);
            } else if ("/live".equals(data.getPath())) {
                intentTransfer = new Intent(this, LiveActivity.class);
            } else if ("/neighbor".equals(data.getPath())) {
                intentTransfer = new Intent(this, NeighborActivity.class);
            } else if ("/talent".equals(data.getPath())) {
                intentTransfer = new Intent(this, TalentListActivity.class);
            } else if ("/guide".equals(data.getPath())) {
                intentTransfer = new Intent(this, GuideActivity.class);
            } else if ("/experience".equals(data.getPath())) {
                intentTransfer = new Intent(this, PlayerActivity.class);
            }else if ("/latest".equals(data.getPath())) {
                intentTransfer = new Intent(this, CikeActivity.class);
            } else if ("/message".equals(data.getPath())) {
                intentTransfer = new Intent(this, HomeActivity.class);
            } else if ("/message/like".equals(data.getPath())) {
                intentTransfer = new Intent(this, MessageDetailActivity.class);
            } else if ("/message/comment".equals(data.getPath())) {
                intentTransfer = new Intent(this, MessageDetailActivity.class);
            } else if ("/message/follow".equals(data.getPath())) {
                intentTransfer = new Intent(this, MessageDetailActivity.class);
            } else if ("/message/system".equals(data.getPath())) {
                intentTransfer = new Intent(this, SystemNoticeActivity.class);
            } else {
                intentTransfer = new Intent(this, HomeActivity.class);
            }
      }else if ("my-member".equals(host)) {
            intentTransfer = new Intent(this, MemberInfoActivity.class);
        } else if ("event".equals(host)) {
            intentTransfer = new Intent(this, HuodongDetailActivity.class);
        } else if ("booking-list".equals(host)) {
            intentTransfer = new Intent(this, OrderManagerActivity.class);
        } else if ("my-party".equals(host)) {
            intentTransfer = new Intent(this, OrderManagerActivity.class);
            intentTransfer.putExtra("type", OrderManagerActivity.PARTY);
        } else if ("order".equals(host)) {
            intentTransfer = new Intent(this, BookingManageDetailActivity.class);
        } else if ("meal".equals(host)) {
            intentTransfer = new Intent(this, MealDetailActivity.class);
        }
}

你可能發現大量的if else 語句不是很是好的選擇。你能夠採用swith case 看不起來更清爽一些。可是使用HashMap 將是咱們比較好的選擇。

HashMap處理 首發定義一個枚舉 SchemeEnum和類SchemeManager

>``` public enum ShemeEnum {
>     Nearby("/near", NearbyActivity.class), NewSku("/new", NewSkuActivity.class),Live("/live", LiveActivity.class),
>     NeighborActivity("/neighbor", NeighborActivity.class),Talent("/talent", NeighborActivity.class),Guide("/guide", GuideActivity.class),
>     Player("/experience", PlayerActivity.class),News("/news", NewsActivity.class),Latest("latest",CikeActivity.class),
>             Message("/message",NeighborActivity.class),Like("/message/like",NeighborActivity.class),
>     Comment("/message/comment",NeighborActivity.class),Follow("/message/follow",NeighborActivity.class),
>     System("/message/system",NeighborActivity.class),event("event",HomeActivity.class);
>     private String key;
>     private Class<?> value;
> 
>     private ShemeEnum(String key, Class<?> value) {
>         this.value = value;
>         this.key = key;
>     }
> 
>     public String getKey() {
>         return key;
>     }
> 
>     public Class<?> getValue() {
>         return value;
>     }
> }

>```
>   public class SchemeManager {
>     private  static HashMap<String, Class> map = new HashMap();
>     private static SchemeManager scheme;
> 
>     public static HashMap initScheme() {
>         ShemeEnum[] values = ShemeEnum.values();
>         int len=values.length;
>         for (int i = 0; i <len ; i++) {
>             map.put(values[i].getKey(), values[i].getValue());
>         }
>         return map;
>     }
> 
>     public static HashMap<String, Class> getMap() {
>         return map;
>     }
> }

scheme 轉化的Activity 將整理成

>```
>  public class UriActivity extends Activity {
>     private SApplication sApplication;
> 
>     @Override
>     protected void onCreate(Bundle savedInstanceState) {
>         super.onCreate(savedInstanceState);
>         setContentView(R.layout.activity_test);
>         Log.e("---UriActivity---", getClass().getName());
>         Uri data = getIntent().getData();
>         sApplication = (SApplication) getApplication();
>         Intent intent = getIntent();
>         if (intent == null || data == null) finish();
>         Intent intentTransfer = null;
>         String host = data.getHost();
>         if (host.equals("list")) {
>             intentTransfer = getIntentTransfer(data.getPath());
>         }   else {
>             intentTransfer = getIntentTransfer(host);
>         }
>         if (intentTransfer != null) {
>             intentTransfer.setData(data);
>             startActivity(intentTransfer);
>         }
>         finish();
>     }
> 
>     private Intent getIntentTransfer(String path) {
>         Object clazz = sApplication.getMap().get(path);
>         Intent intentTransfer;
>         if (clazz != null) {
>             intentTransfer = new Intent(this, (Class<?>) clazz);
>         } else {
>             intentTransfer = new Intent(this, HomeActivity.class);
>         }
>         return intentTransfer;
>     }
> }
> ``

感受UriActivity 變的更簡潔。每次新加scheme 只須要在對應的枚舉中添加相應的scheme 和Activity名稱既能夠正常的跳轉。

5. 攔截uri 跳轉

若是你想在跳轉的途中或者我直接操做相應的某個操做（顯示彈框，去分享等等） 你首先要重寫 WebViewClient shouldOverrideUrlLoading（WebView view, String url）; 來實現攔截的目的。

this.setWebViewClient(new WebViewClient() {
            String failedUrl;

        @Override
            public void onReceivedSslError(WebView view, SslErrorHandler handler, SslError error) {
            }

            @Override
            public void onPageFinished(WebView view, String url) {
                super.onPageFinished(view, url);
            }

            @Override
            public boolean shouldOverrideUrlLoading(WebView view, String url) {
                //TODO 判斷是否要攔截。若是須要作你的攔截以後的動做。
                //不須要直接跳轉（看第3條）。 
                return true;
            }
        });
    }

這樣經過H5 來打開相應的activity而且傳遞參數的相關內容介紹完。下一節。咱們將講解Activity 傳遞給html 數據，以及調用相關的方法。