JsCallback关联的WebView改为软引用，同时增加其apply时的异常情况

pedant · Nov 27, 2014 · 23fed5d · 23fed5d
1 parent 004006e
commit 23fed5d
Show file tree

Hide file tree

Showing 2 changed files with 30 additions and 8 deletions.
diff --git a/library/src/main/java/cn/pedant/SafeWebViewBridge/JsCallback.java b/library/src/main/java/cn/pedant/SafeWebViewBridge/JsCallback.java
@@ -8,23 +8,33 @@
 
 package cn.pedant.SafeWebViewBridge;
 
-import android.webkit.WebView;
 import android.util.Log;
+import android.webkit.WebView;
+
+import java.lang.ref.SoftReference;
 
 public class JsCallback {
     private static final String CALLBACK_JS_FORMAT = "javascript:%s.callback(%d, %d %s);";
     private int mIndex;
-    private WebView mWebView;
+    private boolean mCouldGoOn;
+    private SoftReference<WebView> mWebViewRef;
     private int mIsPermanent;
     private String mInjectedName;
 
     public JsCallback (WebView view, String injectedName, int index) {
-        mWebView = view;
+        mCouldGoOn = true;
+        mWebViewRef = new SoftReference<WebView>(view);
         mInjectedName = injectedName;
         mIndex = index;
     }
 
-    public void apply (Object... args) {
+    public void apply (Object... args) throws JsCallbackException {
+        if (mWebViewRef.get() == null) {
+            throw new JsCallbackException("the WebView related to the JsCallback has been recycled");
+        }
+        if (!mCouldGoOn) {
+            throw new JsCallbackException("the JsCallback isn't permanent,cannot be called more than once");
+        }
         StringBuilder sb = new StringBuilder();
         for (Object arg : args){
             sb.append(",");
@@ -39,10 +49,17 @@ public void apply (Object... args) {
         }
         String execJs = String.format(CALLBACK_JS_FORMAT, mInjectedName, mIndex, mIsPermanent, sb.toString());
         Log.d("JsCallBack", execJs);
-        mWebView.loadUrl(execJs);
+        mWebViewRef.get().loadUrl(execJs);
+        mCouldGoOn = mIsPermanent > 0;
     }
 
     public void setPermanent (boolean value) {
         mIsPermanent = value ? 1 : 0;
     }
+
+    public static class JsCallbackException extends Exception {
+        public JsCallbackException (String msg) {
+            super(msg);
+        }
+    }
 }
diff --git a/sample/src/main/java/cn/pedant/SafeWebViewBridge/sample/HostJsScope.java b/sample/src/main/java/cn/pedant/SafeWebViewBridge/sample/HostJsScope.java
@@ -16,8 +16,6 @@
 import android.telephony.TelephonyManager;
 import android.webkit.WebView;
 import android.widget.Toast;
-import cn.pedant.SafeWebViewBridge.JsCallback;
-import cn.pedant.SafeWebViewBridge.sample.util.TaskExecutor;
 
 import org.json.JSONException;
 import org.json.JSONObject;
@@ -26,6 +24,9 @@
 import java.util.Iterator;
 import java.util.List;
 
+import cn.pedant.SafeWebViewBridge.JsCallback;
+import cn.pedant.SafeWebViewBridge.sample.util.TaskExecutor;
+
 //HostJsScope中需要被JS调用的函数，必须定义成public static，且必须包含WebView这个参数
 public class HostJsScope {
     /**
@@ -174,7 +175,11 @@ public static void delayJsCallBack(WebView view, int ms, final String backMsg, f
         TaskExecutor.scheduleTaskOnUiThread(ms * 1000, new Runnable() {
             @Override
             public void run() {
-                jsCallback.apply(backMsg);
+                try {
+                    jsCallback.apply(backMsg);
+                } catch (JsCallback.JsCallbackException je) {
+                    je.printStackTrace();
+                }
             }
         });
     }