Android WebView开发之自定义WebView工具框

    /**
     * 长按弹出ActionMode菜单样式
     * @param callback
     * @param type
     * @return
     */
    @Override
    public ActionMode startActionMode(Callback callback, int type) {
        Logger.d(TAG, "startActionMode--callback:" + callback + " type:" + type);
        ActionMode actionMode = super.startActionMode(callback, type);
        return resolveActionMode(actionMode);
    }

    private ActionMode resolveActionMode(ActionMode actionMode) {
        if (actionMode != null) {
            final Menu menu = actionMode.getMenu();
            mActionMode = actionMode;
            //清除系统自定item选项
            menu.clear();
 
            /**
             * 为菜单item重新赋值
             */
            for (int i = 0; i < mActionList.size(); i++) {
                menu.add(mActionList.get(i));
                //可以为每个item添加icon
                //menu.getItem(i).setIcon(R.drawable.ic_launcher);
            }
 
            for (int i = 0; i < menu.size(); i++) {
                MenuItem menuItem = menu.getItem(i);
                /**
                 * 新添item的点击事件【可根据不同个item点击事件，来进行相关的业务处理】
                 */
                menuItem.setOnMenuItemClickListener(new OnMenuItemClickListener() {
                    @Override
                    public boolean onMenuItemClick(MenuItem item) {
                        Logger.d(TAG, item.getTitle().toString());
                        getSelectedData((String) item.getTitle());
                        releaseAction();
                        return true;
                    }
                });
            }
        }
 
        mActionMode = actionMode;
        return actionMode;
    }

    private void initData() {
        mActionList = new ArrayList<>();
        //扩选
        mActionList.add(GlobalConstant.ENLARGE);
        //复制
        mActionList.add(GlobalConstant.COPY);
        //分享
        mActionList.add(GlobalConstant.SHARE);
    }

    /**
     * Android调用JS的代码方式有2种：
     * 1、通过WebView的loadUrl()
     * 2、通过WebView的evaluateJavaScript()
     * <p>
     * 点击的时候，获取网页中选择的文本，回掉到原生中的js接口
     *
     * @param title 传入点击的item文本，一起通过js返回给原生接口
     */
    private void getSelectedData(String title) {
 
        String js = "(function getSelectedText() {" +
                "var txt;" +
                "var title = \"" + title + "\";" +
                "if (window.getSelection) {" +
                "txt = window.getSelection().toString();" +
                "} else if (window.document.getSelection) {" +
                "txt = window.document.getSelection().toString();" +
                "} else if (window.document.selection) {" +
                "txt = window.document.selection.createRange().text;" +
                "}" +
                "JSInterface.callback(txt,title);" +
                "})()";
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
            evaluateJavascript("javascript:" + js, new ValueCallback<String>() {
                @Override
                public void onReceiveValue(String value) {
                    //此处为js返回结果
                    Logger.d(TAG, "value:" + value);
                }
            });
        } else {
            loadUrl("javascript:" + js);
        }
    }

    private void linkJSInterface() {
        //Js调用native的方式一
        addJavascriptInterface(new ActionSelectInterface(this), "JSInterface");
    }

    /**
     * JS调用android原生方法1：
     * 通过WebView的addJavascriptInterface()进行对象映射
     */
    public class ActionSelectInterface {
 
        private ActionWebView mActionWebView;
 
        public ActionSelectInterface(ActionWebView actionWebView) {
            mActionWebView = actionWebView;
        }
 
        @JavascriptInterface
        public void callback(final String value, final String title) {
            Logger.d(TAG, "currentThread:" + Thread.currentThread());
            post(new Runnable() {
                @Override
                public void run() {
                    if (mActionSelectListener != null) {
                        mActionSelectListener.onClick(title, value);
                    }
                }
            });
        }
    }