在下面的代码中，按钮“alt2”显示但不警告“hi”
这是添加按钮的正确方法吗？
video:not(.video-js) {
width: 100%;
height: auto !important;
}
答案 0 :(得分：2)
package com.ambujkathotiya.swachhb.activity;
import android.Manifest;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.os.StrictMode;
import android.provider.MediaStore;
import android.provider.Settings;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.ImageButton;
import android.widget.Toast;
import com.ambujkathotiya.swachhb.R;
import java.io.File;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
public class MainActivity extends AppCompatActivity implements LocationListener {
private static String TAG = MainActivity.class.getSimpleName();
String longi;
String lat;
LocationManager locationManager;
// Camera activity request codes
private static final int CAMERA_CAPTURE_IMAGE_REQUEST_CODE = 100;
public static final int MEDIA_TYPE_IMAGE = 1;
private Uri fileUri; // file url to store image/video
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Main code
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.GINGERBREAD) {
StrictMode.ThreadPolicy tp = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(tp);
}
// Changing action bar background color
// These two lines are not needed
ImageButton btnCapturePicture = (ImageButton) findViewById(R.id.btnCapturePicture);
/**
* Capture image button click event
*/
btnCapturePicture.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// capture picture
ConnectivityManager connectivity = (ConnectivityManager) getApplicationContext().getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netinfo = connectivity.getActiveNetworkInfo();
if (netinfo != null && netinfo.isConnected()) {
// Internet Connection is present
//Check if location services is switched on or not
LocationManager locManager = (LocationManager) getSystemService(LOCATION_SERVICE);
if (locManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
//Location services enabled
//Call the camera
captureImage();
} else {
//Location services not enabled
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(intent);
}
} else {
// Internet connection is not present
Toast.makeText(getApplicationContext(),
"Sorry! You need an internet connection to proceed.",
Toast.LENGTH_LONG).show();
}
}
});
// Checking camera availability
if (!isDeviceSupportCamera()) {
Toast.makeText(getApplicationContext(),
"Sorry! Your device doesn't support camera",
Toast.LENGTH_LONG).show();
// will close the app if the device does't have camera
finish();
}
}
/**
* Checking device has camera hardware or not
* */
private boolean isDeviceSupportCamera() {
// this device has a camera
// no camera on this device
return getApplicationContext().getPackageManager().hasSystemFeature(
PackageManager.FEATURE_CAMERA);
}
/**
* Launching camera app to capture image
*/
private void captureImage() {
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
fileUri = getOutputMediaFileUri(MEDIA_TYPE_IMAGE);
intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);
// start the image capture Intent
startActivityForResult(intent, CAMERA_CAPTURE_IMAGE_REQUEST_CODE);
}
/**
* Here we store the file url as it will be null after returning from camera
* app
*/
@Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
// save file url in bundle as it will be null on screen orientation
// changes
outState.putParcelable("file_uri", fileUri);
}
@Override
protected void onRestoreInstanceState(Bundle savedInstanceState) {
super.onRestoreInstanceState(savedInstanceState);
// get the file url
fileUri = savedInstanceState.getParcelable("file_uri");
}
/**
* Receiving activity result method will be called after closing the camera
* */
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// if the result is capturing Image
if (requestCode == CAMERA_CAPTURE_IMAGE_REQUEST_CODE) {
if (resultCode == RESULT_OK) {
// successfully captured the image
// launching upload activity
getLocation();
Log.d(TAG, "hi" + lat);
Log.d(TAG, "hello"+longi);
launchUploadActivity(true);
} else if (resultCode == RESULT_CANCELED) {
// user cancelled Image capture
Toast.makeText(getApplicationContext(),
"User cancelled image capture", Toast.LENGTH_SHORT)
.show();
} else {
// failed to capture image
Toast.makeText(getApplicationContext(),
"Sorry! Failed to capture image", Toast.LENGTH_SHORT)
.show();
}
}
}
private void launchUploadActivity(boolean isImage){
Intent i = new Intent(MainActivity.this, UploadActivity.class);
i.putExtra("filePath", fileUri.getPath());
i.putExtra("isImage", isImage);
i.putExtra("lat",lat);
i.putExtra("longi",longi);
startActivity(i);
}
/**
* ------------ Helper Methods ----------------------
* */
/**
* Creating file uri to store image/video
*/
public Uri getOutputMediaFileUri(int type) {
return Uri.fromFile(getOutputMediaFile(type));
}
/**
* returning image / video
*/
private static File getOutputMediaFile(int type) {
// External sdcard location
File mediaStorageDir = new File(
Environment
.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES),
Config.IMAGE_DIRECTORY_NAME);
// Create the storage directory if it does not exist
if (!mediaStorageDir.exists()) {
if (!mediaStorageDir.mkdirs()) {
Log.d(TAG, "Oops! Failed create "
+ Config.IMAGE_DIRECTORY_NAME + " directory");
return null;
}
}
// Create a media file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss",
Locale.getDefault()).format(new Date());
File mediaFile;
if (type == MEDIA_TYPE_IMAGE) {
mediaFile = new File(mediaStorageDir.getPath() + File.separator
+ "IMG_" + timeStamp + ".jpg");
} else {
return null;
}
return mediaFile;
}
@Override
public void onLocationChanged(Location location) {
}
@Override
public void onProviderDisabled(String provider) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
public void getLocation()
{
//Location code
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
//If location manager returns not null,then save the lat and long
if (locationManager != null) {
if (ContextCompat.checkSelfPermission(getApplicationContext(), Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED || ContextCompat.checkSelfPermission(getApplicationContext(), Manifest.permission.ACCESS_COARSE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0,this);
Location location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, this);
Location location1 = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
double latitude = location.getLatitude();
double longitude = location.getLongitude();
lat = Double.toString(latitude);
longi = Double.toString(longitude);
}
else if(location1 != null){
double latitude = location1.getLatitude();
double longitude = location1.getLongitude();
lat = Double.toString(latitude);
longi = Double.toString(longitude);
}
else {
finish();
}
} else {
finish();
}
//Remove the request for location updates.
locationManager.removeUpdates(this);
} else {
finish();
}
}
}
$("#add").click(function() {
$("#test").html("<button id='alt2'>alt2</button>");
});
$("#alt").click(function() {
alert("hi");
});
$(document).on('click',"#alt2",function() { // use .on()
alert("hi 2");
});
使用.on()动态添加元素。
描述：将一个或多个事件的事件处理函数附加到所选元素。
答案 1 :(得分：2)
on("click")...。我还建议您使用on("click")...代替.("click")。 .("click")这个人可能会错过第二次开火
<body>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/2.1.4/jquery.min.js"></script>
<div id="test"></div><br>
<button id="add">add</button><br>
<button id='alt'>alt1</button>
<script type="text/javascript" >
$(function(){
$(document).on("click", "#add", function(e) {
e.preventDefault();
$("#test").html("<button id='alt2'>alt2</button>");
});
$(document).on("click", "#alt", function(e) {
e.preventDefault();
alert("hi 1");
});
$(document).on("click", "#alt2", function(e) {
e.preventDefault();
alert("hi 2");
});
});
</script>
</body>