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How do I find out if the GPS of an Android device is enabled
...manager.isProviderEnabled( LocationManager.GPS_PROVIDER ) ) {
buildAlertMessageNoGps();
}
private void buildAlertMessageNoGps() {
final AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage("Your GPS seems to be disabled, do you want to enable it?")
...
How can I process each letter of text using Javascript?
I would like to alert each individual letter of a string, but I am unsure how to do this.
23 Answers
...
Is JavaScript guaranteed to be single-threaded?
... because you called focus() directly, they could happen because you called alert(), or opened a pop-up window, or anything else that moves the focus.
This can also result in other events. For example add an i.onchange listener and type something in the input before the focus() call unfocuses it, an...
JavaScript null check
...” is different from the value undefined.
An undefined variable:
var a;
alert(b); // ReferenceError: b is not defined
A variable with the value undefined:
var a;
alert(a); // Alerts “undefined”
When a function takes an argument, that argument is always declared even if its value is undef...
image.onload event and browser cache
I want to create an alert box after an image is loaded, but if the image is saved in the browser cache, the .onload event will not be fired.
...
Escaping HTML strings with jQuery
... class="someClass">text</div>
var someHtmlString = "<script>alert('hi!');</script>";
// set a DIV's text:
$("div.someClass").text(someHtmlString);
// after:
// <div class="someClass">&lt;script&gt;alert('hi!');&lt;/script&gt;</div>
// get the text ...
Is it possible to ping a server from Javascript?
... url: 'ping.html',
success: function(result){
alert('reply');
},
error: function(result){
alert('timeout/error');
}
});
}
</script>
...
Checking if jquery is loaded using Javascript
...ction() {
if (window.jQuery) {
// jQuery is loaded
alert("Yeah!");
} else {
// jQuery is not loaded
alert("Doesn't Work");
}
}
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SensorUtil 传感器工具扩展：在后台和屏幕关闭时保持传感器工作 · App Inv...
...用程序进入后台时，传感器组件会自动禁用。此扩展提供了三个组件，使传感器能够在后台运行、屏幕关闭和打盹模式下继续采集数据。
主要功能
在后台/后台执行期间保持传感器功能
通过前台服务（Foreg...