问题
Edit: This snipped worked in the end. I had been trying this before but was actually experiencing a scoping issue with my javascript. I had appBack() defined in document.onready. Simply re-scoping that function to *window.*appBack = function(). Done the business. Hope this helps someone.
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
WebView.loadUrl("javascript:appBack()");
return true;
}
return super.onKeyDown(keyCode, event);
}
Within a webview application the back navigation is handled with a custom JS function appBack() I've been trying to figure out a way to intercept the android physical back button and call that javascript function instead. Here is my activity file. Its very basic, sets up a webview and listens for the back button click. Currently when the user clicks this physical back button it runs mWebView.goBack(). Which is where I would like to perform javascript:appBack()
package com.stgeorgeplc.app;
import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.webkit.WebView;
public class StGeorgePLCliteActivity extends Activity {
/** Called when the activity is first created. */
WebView mWebView;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mWebView = (WebView) findViewById(R.id.webview);
mWebView.getSettings().setJavaScriptEnabled(true);
mWebView.getSettings().setBuiltInZoomControls(true);
mWebView.loadUrl("file:///android_asset/www/index.html");
}
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
mWebView.goBack();
return true;
}
return super.onKeyDown(keyCode, event);
}
}
来源:https://stackoverflow.com/questions/7916624/calling-javascript-functions-in-a-webview-from-activity-class