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Interaction between Android and Javascript. Javascript needs to run in a browser or android webview component. Javascript must have a carrier HTML file.
Put it under the assets folder of the android project.
First, I will post the code first:
The content of the Main. xml layout file is as follows:
<? XML version = "1.0" encoding = "UTF-8"?>
<Linearlayout xmlns: Android = "http://schemas.android.com/apk/res/android"
Android: layout_width = "fill_parent"
Android: layout_height = "fill_parent"
Android: Orientation = "vertical">
<Edittext
Android: Id = "@ + ID/TXT"
Android: layout_width = "fill_parent"
Android: layout_height = "wrap_content"/>
<Button
Android: Id = "@ + ID/BTN"
Android: layout_width = "fill_parent"
Android: layout_height = "wrap_content"
Android: text = "send to JavaScript"/>
<Button
Android: Id = "@ + ID/btnno"
Android: layout_width = "fill_parent"
Android: layout_height = "wrap_content"
Android: text = "send to JavaScript (No parameter)"/>
<Textview
Android: Id = "@ + ID/Show"
Android: layout_width = "fill_parent"
Android: layout_height = "wrap_content"/>
<Webview
Android: Id = "@ + ID/WV"
Android: layout_width = "fill_parent"
Android: layout_height = "fill_parent"/>
</Linearlayout>
The HTML content in the assets folder is as follows:
<! Doctype HTML public "-// wapforum // dtd xhtml mobile 1.0 //" http://www.wapforum.org/DTD/xhtml-mobile10.dtd ">
<HTML xmlns = "http://www.w3.org/1999/xhtml">
<Head>
<Meta http-equiv = "Content-Type" content = "text/html; charset = UTF-8"/>
<Script language = "JavaScript" type = "text/JavaScript">
Function get4android (STR ){
Document. getelementbyid ("show"). innerhtml = "this is a message from Android :"
+ STR;
}
Function get4androidnoparameter (){
Alert ("get4androidnoparameter ");
}
Function send2android (){
VaR STR = Document. getelementbyid ("mess"). value;
Window. myjs. runonandroidjavascript (STR); // call the android Function
}
Function send2androidnoparameter (){
Window. myjs. runonandroidjavascript (); // call the parameter-free function of Android.
}
</SCRIPT>
</Head>
<Body>
<Input type = "text" id = "mess"/>
<Input type = "button" value = "send to Android (having parameters)" onclick = "send2android ()"/>
<Input type = "button" value = "send to Android (no parameters)" onclick = "send2androidnoparameter ()"/>
<Div id = "show"> </div>
</Body>
</Html>
The activity code is as follows:
Package com. BroadVision. jstest;
Import Android. App. activity;
Import Android. OS. Bundle;
Import Android. OS. Handler;
Import Android. View. view;
Import Android. View. View. onclicklistener;
Import Android. WebKit. webchromeclient;
Import Android. WebKit. websettings;
Import Android. WebKit. webview;
Import Android. widget. Button;
Import Android. widget. edittext;
Import Android. widget. textview;
Import Android. widget. Toast;
Public class jstestactivity extends activity {
Private edittext txt;
Private webview WV;
Private button BTN;
Private button btnno;
Private handler H = new handler ();
@ Override
Public void oncreate (bundle savedinstancestate ){
Super. oncreate (savedinstancestate );
Setcontentview (R. layout. Main );
TXT = (edittext) findviewbyid(r.id.txt );
WV = (webview) findviewbyid (R. Id. WV );
BTN = (button) findviewbyid (R. Id. BTN );
Btnno = (button) findviewbyid (R. Id. btnno );
WV. requestfocus (view. focus_down | view. focus_up );
Websettings = WV. getsettings ();
Websettings. setjavascriptenabled (true );
Websettings. setlighttouchenabled (true );
Websettings. setsaveformdata (false );
Websettings. setsavepassword (false );
Websettings. setsuppzoom zoom (false );
// Do not use addjavascriptinterface () unless all of the HTML in this
// Webview was written by you in general, Java and JavaScript cannot call each other unless you know that JavaScript code is safe.
// The Java object that is bound runs in another thread and not in
// Thread that it was constructed in. myjs is a custom interface for JavaScript access.
WV. addjavascriptinterface (New runjavascript (), "myjs ");
// The webchromeclient can invoke "alert ()" js method
WV. setwebchromeclient (New webchromeclient ());
String url = "file: // android_asset/android.html ";
WV. loadurl (URL );
// Webview: the format of the HTML file path under the assets folder to be called is as follows: file: // android_asset/html file name
BTN. setonclicklistener (New onclicklistener (){
@ Override
Public void onclick (view v ){
// Call the JavaScript function get4android (STR)
Call a javascript constructor with Parameters
WV. loadurl ("javascript: get4android ('" + TXT. gettext (). tostring () + "')");
WV. requestfocus (view. focus_down | view. focus_up );
}
});
Btnno. setonclicklistener (New onclicklistener (){
@ Override
Public void onclick (view v ){
System. Out. println ("No parameter ");
// Call the JavaScript function get4androidnoparameter () Java to call functions without Parameters
WV. loadurl ("javascript: get4androidnoparameter ()");
WV. requestfocus (view. focus_down | view. focus_up );
}
});
}
// The Java object that is bound runs in another thread and not in the thread
// That it was constructed in. One sentence in the document!
Class runjavascript {// This Java object is bound to another thread,
Public void runonandroidjavascript (final string Str ){
H. Post (New runnable (){
@ Override
Public void run () {// special note here
Textview show = (textview) findviewbyid (R. Id. Show );
Show. settext ("this is a message from javascript:" + Str );
WV. requestfocus (view. focus_down | view. focus_up );
}
});
}
Public void runonandroidjavascript (){
H. Post (New runnable (){
@ Override
Public void run () {// special note here
Toast. maketext (jstestactivity. This,
"This is a message from JavaScript", Toast. length_long). Show ();
WV. requestfocus (view. focus_down | view. focus_up );
}
});
}
}
}
Note:
1. Java can be overloaded based on parameters with the same method name. It is best not to use JavaScript like this.
2. webview. setwebchromeclient (New webchromeclient (); after the Javascript alert method is set, it can be called in webview.
3. websettings. setlighttouchenabled (true); and webview. requestfocus (view. focus_down | view. focus_up );
Communication to solve the problem that the input boxes in edittext and webview cannot obtain the focus respectively.
Project
I hope it will help you. If you need this project, I can send it to you.
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