javascript - 如何使用 WebAppInterface(Javascript 接口(interface))操作 Android View ？

Question

当我的 Android WebView 运行时，我使用 WebAppInterface 从 Javascript 获取数据。从 Javascript 获取一些数据后，如何立即操作 Android View ？

public class WebAppInterface {
    Context mContext;

    /** Instantiate the interface and set the context */
    WebAppInterface(Context c) {
        mContext = c;
    }

    //This function can only be called by javascript
    @android.webkit.JavascriptInterface
    public void sendDataToJava(float currTime, String url) {

        videoUrl = url;
        videoTime = Math.round(currTime);

        //use references to views to change stuff
        videoView.seekTo(videoTime); //ERROR HERE
       //ERROR: Only the original thread that created a view hierarchy can touch its views


    }


}

Answer 1

您需要保留对 View 包含 Activity 的引用，并使用可运行的 Activity.runOnUiThread 方法调用与 View 相关的代码。

它看起来像这样:

public class WebAppInterface {
    Context mContext;
    Activity mActivity;

    /** Instantiate the interface and set the context */
    WebAppInterface(Context c, Activity a) {
        mContext = c;
        mActivity = a;

    }

    //This function can only be called by javascript
    @android.webkit.JavascriptInterface
    public void sendDataToJava(float currTime, String url) {

        videoUrl = url;
        videoTime = Math.round(currTime);

        mActivity.runOnUiThread(new Runnable() {
            @Override
            public void run() {
                videoView.seekTo(videoTime); 
            }
        });
    }

}