我的 MainActivity.java
中包含此代码onBackPressed
@Override
public void onBackPressed() {
if (getFragmentManager().getBackStackEntryCount() > 0) {
getFragmentManager().popBackStack();
} else {
super.onBackPressed();
}
}
我有 HomeFragment.java
我想要的是当我在HomeFragment.java ..
我想添加双击以退出我的应用程序..
我该怎么做？
这是我的 MainActivity.java
package com.example.administrator.mosbeau;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.Handler;
import android.provider.Settings;
import android.support.v7.app.ActionBarActivity;
import android.app.Fragment;
import android.app.FragmentManager;
import android.os.Bundle;
import android.util.Base64;
import android.util.Log;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.support.v4.widget.DrawerLayout;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import android.widget.SearchView;
import android.widget.TextView;
import android.widget.Toast;
import org.json.JSONArray;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import android.content.pm.Signature;
import com.facebook.appevents.AppEventsLogger;
@SuppressWarnings("deprecation")
public class MainActivity extends ActionBarActivity
implements NavigationDrawerFragment.NavigationDrawerCallbacks {
/**
* Fragment managing the behaviors, interactions and presentation of the navigation drawer.
*/
private NavigationDrawerFragment mNavigationDrawerFragment;
/**
* Used to store the last screen title. For use in {@link #//restoreActionBar()}.
*/
private CharSequence mTitle;
UserLocalStore userLocalStore;
String customersid, countrycode, carttotal, stateid;
SearchView searchView;
RelativeLayout notifCount;
TextView tv;
public static final int CONNECTION_TIMEOUT = 1000 * 15;
public static final String SERVER_ADDRESS = "http://shop.mosbeau.com.ph/android/";
String myJSONcarttotal;
JSONArray jsonarraycarttotal;
private static final int TIME_DELAY = 2000;
private static long back_pressed;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Connectivity connectivity=new Connectivity();
if(connectivity.isConnected(MainActivity.this)) {
// Add code to print out the key hash
/*try {
PackageInfo info = getPackageManager().getPackageInfo(
"com.administrator.mosbeau",
PackageManager.GET_SIGNATURES);
for (Signature signature : info.signatures) {
MessageDigest md = MessageDigest.getInstance("SHA");
md.update(signature.toByteArray());
Log.d("KeyHash:", Base64.encodeToString(md.digest(), Base64.DEFAULT));
}
} catch (PackageManager.NameNotFoundException e) {
} catch (NoSuchAlgorithmException e) {
}*/
}else{
nointernet();
}
userLocalStore = new UserLocalStore(this);
mNavigationDrawerFragment = (NavigationDrawerFragment)
getSupportFragmentManager().findFragmentById(R.id.navigation_drawer);
mTitle = getTitle();
// Set up the drawer.
mNavigationDrawerFragment.setUp(
R.id.navigation_drawer,
(DrawerLayout) findViewById(R.id.drawer_layout));
}
public void onStart() {
super.onStart();
if(authenticate() == true){
displayUserDetails();
}else{
Intent myIntent = new Intent(MainActivity.this, IndexActivity.class);
startActivity(myIntent);
}
}
private boolean authenticate() {
if (userLocalStore.getLoggedInUser() == null) {
Intent myIntent = new Intent(MainActivity.this, IndexActivity.class);
startActivity(myIntent);
return false;
}
return true;
}
private void displayUserDetails(){
User user = userLocalStore.getLoggedInUser();
customersid = user.customers_id;
countrycode = user.customers_countryid;
stateid = user.customers_stateid;
if(customersid==""){
Intent myIntent = new Intent(MainActivity.this, IndexActivity.class);
startActivity(myIntent);
}
}
@Override
public void onNavigationDrawerItemSelected(int position,String id,String name,String image2) {
// update the main content by replacing fragments
FragmentManager fragmentManager = getFragmentManager();
// NEW STUFF
if(position == 0){
fragmentManager.beginTransaction()
.replace(R.id.container, HomeFragment.newInstance())
.commit();
}
else if (position == 1){
fragmentManager.beginTransaction()
.replace(R.id.container, CategoryFragment.newInstance(id,name,countrycode,image2,customersid,stateid))
.commit();
}
else if (position == 2){
fragmentManager.beginTransaction()
.replace(R.id.container, AccountFragment.newInstance(customersid))
.commit();
}
else if (position == 3){
fragmentManager.beginTransaction()
.replace(R.id.container, ReferFragment.newInstance(customersid))
.commit();
}
else if (position == 4){
fragmentManager.beginTransaction()
.replace(R.id.container, AboutFragment.newInstance(customersid))
.commit();
}
else if (position == 5){
fragmentManager.beginTransaction()
.replace(R.id.container, PolicyFragment.newInstance(customersid))
.commit();
}
else if (position == 6){
fragmentManager.beginTransaction()
.replace(R.id.container, TermsFragment.newInstance(customersid))
.commit();
}
else if (position == 7){
fragmentManager.beginTransaction()
.replace(R.id.container, ContactusFragment.newInstance(customersid))
.commit();
}
else if (position == 8){
userLocalStore.clearUserData();
userLocalStore.setUserLoggedIn(false);
Intent myIntent = new Intent(this, IndexActivity.class);
startActivity(myIntent);
}
else if (position == 101){
fragmentManager.beginTransaction()
.replace(R.id.container, CartFragment.newInstance(customersid,countrycode,stateid,"a"))
.commit();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
if (!mNavigationDrawerFragment.isDrawerOpen()) {
// Only show items in the action bar relevant to this screen
// if the drawer is not showing. Otherwise, let the drawer
// decide what to show in the action bar.
getMenuInflater().inflate(R.menu.main, menu);
//restoreActionBar();
// HERE RETURNS NULL
searchView = (SearchView) menu.findItem(R.id.action_search).getActionView();
int searchImgId = getResources().getIdentifier("android:id/search_button", null, null);
ImageView v = (ImageView) searchView.findViewById(searchImgId);
v.setImageResource(R.drawable.action_searchm);
if (searchView != null) {
final Menu menu_block = menu;
searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
@Override
public boolean onQueryTextSubmit(String query) {
// collapse the view ?
//menu_block.findItem(R.id.action_search).collapseActionView();
SearchFragment searchFragment = SearchFragment.newInstance(query,countrycode,customersid,stateid);
FragmentManager fragmentManager = getFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.container, searchFragment)
.addToBackStack(null)
.commit();
return false;
}
@Override
public boolean onQueryTextChange(String newText) {
// search goes here !!
// listAdapter.getFilter().filter(query);
return false;
}
});
//Log.i("sales module", "SearchView QWE");
}else{
//Log.i("sales module", "SearchView is null");
}
return true;
}
return super.onCreateOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
/*if (id == R.id.action_settings) {
return true;
}*/
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
private static final String ARG_SECTION_NUMBER = "section_number";
/**
* Returns a new instance of this fragment for the given section
* number.
*/
public static PlaceholderFragment newInstance(int sectionNumber) {
PlaceholderFragment fragment = new PlaceholderFragment();
Bundle args = new Bundle();
args.putInt(ARG_SECTION_NUMBER, sectionNumber);
fragment.setArguments(args);
return fragment;
}
public PlaceholderFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
return rootView;
}
}
/*@Override
public void onBackPressed() {
if (getFragmentManager().getBackStackEntryCount() > 0) {
getFragmentManager().popBackStack();
} else {
super.onBackPressed();
}
}*/
boolean doubleBackToExitPressedOnce = false;
@Override
public void onBackPressed() {
if (getFragmentManager().getBackStackEntryCount() > 0) {
getFragmentManager().popBackStack();
} else {
Fragment fragment = getFragmentManager().findFragmentById(R.id.textHomeBack);
if (fragment instanceof HomeFragment) {
if (doubleBackToExitPressedOnce) {
super.onBackPressed();
return;
}
this.doubleBackToExitPressedOnce = true;
Toast.makeText(this, "Please click BACK again to exit", Toast.LENGTH_SHORT).show();
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
doubleBackToExitPressedOnce = false;
}
}, 2000);
}
else {
super.onBackPressed();
}
}
}
public void nointernet(){
AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(this);
dialogBuilder.setMessage("There seems to be a problem with your connection.");
dialogBuilder.setNegativeButton("Edit Settings", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
//Stop the activity
startActivity(new Intent(Settings.ACTION_WIFI_SETTINGS));
}
});
dialogBuilder.setPositiveButton("Reload", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
//Stop the activity
Intent intent = getIntent();
finish();
startActivity(intent);
}
});
AlertDialog dialog = dialogBuilder.show();
TextView messageText = (TextView)dialog.findViewById(android.R.id.message);
messageText.setGravity(Gravity.CENTER);
dialog.setCanceledOnTouchOutside(false);
dialog.setCancelable(false);
dialog.show();
}
}
这是我的 homelayout.xml
<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:fillViewport="false"
android:background="#fffff1f1">
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent"
android:background="#fffff1f1"
android:padding="10dp"
android:orientation="horizontal"
android:gravity="center_horizontal">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/textHomeBack"
android:visibility="invisible"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/textCountryId"
android:visibility="invisible"/>
<FrameLayout
android:id="@+id/framelayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:minHeight="200dp">
<ImageView
android:id="@+id/imageView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:adjustViewBounds="true"
android:gravity="center"
android:layout_gravity="center"/>
<ProgressBar
android:id="@+id/loading"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
android:layout_gravity="center" />
</FrameLayout>
<FrameLayout
android:id="@+id/framelayout2"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@+id/framelayout"
android:layout_marginTop="10dp"
android:layout_marginBottom="10dp"
android:minHeight="130dp">
<HorizontalScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scrollbars="horizontal"
android:id="@+id/horizontalScrollView"
android:fillViewport="false">
<LinearLayout
android:id="@+id/linear"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"/>
</HorizontalScrollView>
<ProgressBar
android:id="@+id/loading2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
android:layout_gravity="center" />
</FrameLayout>
<FrameLayout
android:id="@+id/framelayout3"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@+id/framelayout2"
android:minHeight="200dp">
<ImageView
android:id="@+id/imageView3"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:adjustViewBounds="true"
android:gravity="center"
android:layout_gravity="center" />
<ProgressBar
android:id="@+id/loading3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
android:layout_gravity="center" />
</FrameLayout>
</RelativeLayout>
</ScrollView>
请帮帮我。
答案 0 :(得分：2)
试试这样：
boolean doubleBackToExitPressedOnce = false;
@Override
public void onBackPressed() {
if (getFragmentManager().getBackStackEntryCount() > 0) {
getFragmentManager().popBackStack();
} else {
Fragment fragment = getFragmentManager().findFragmentById(R.id.fragment_container);
if (fragment instanceof HomeFragment) {
if (doubleBackToExitPressedOnce) {
super.onBackPressed();
return;
}
this.doubleBackToExitPressedOnce = true;
Toast.makeText(this, "Please click BACK again to exit", Toast.LENGTH_SHORT).show();
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
doubleBackToExitPressedOnce = false;
}
}, 2000);
}
else {
super.onBackPressed();
}
}
}
答案 1 :(得分：2)
试试这段代码..
long back_pressed=0;
@Override
public void onBackPressed()
{
if (back_pressed + 2000 > System.currentTimeMillis())
super.onBackPressed();
else
{
Snackbar snackbar=Snackbar.make(view, "Double Tap to Exit!", Snackbar.LENGTH_SHORT);
View view=snackbar.getView();
view.setBackgroundColor(getResources().getColor(R.color.white));
snackbar.show();
back_pressed = System.currentTimeMillis();
}
}
答案 2 :(得分：0)
此代码必须帮助您完成任务。
private static final int TIME_INTERVAL = 2000; // # milliseconds, desired time passed between two back presses.
private long mBackPressed;
private void setFragment(Fragment fragment, int position) {
mTextViewAppTitle.setText(navTitles[position]);
getSupportFragmentManager()
.beginTransaction()
.add(R.id.main_content, fragment)
.addToBackStack(navTitles[position])
.commit();
}
@Override
public void onBackPressed() {
if (getSupportFragmentManager().getBackStackEntryCount() != 0) {
super.onBackPressed();
return;
}
if (mBackPressed + TIME_INTERVAL > System.currentTimeMillis()) {
super.onBackPressed();
return;
} else {
Utils.showToast(this, "Tap back button in order to Exit");
}
mBackPressed = System.currentTimeMillis();
}
答案 3 :(得分：0)
我没有双击退出任何方式，我不知道这是对的，但你可以按照方式解决问题
@Override
public void onBackPressed() {
// TODO Auto-generated method stub
if (count == 0)
count = 1;
else
count = 2;
android.os.Handler h = new android.os.Handler();
h.postDelayed(new Runnable() {
@Override
public void run() {
if (count == 2) {
// Just Put Your Code for Exit
Log.d("DoubleTap", "Exit");
}
count= 0;
}
}, 500);//You can set double tap interval currently set half second
// super.onBackPressed();
}
注意： - 将count声明为全局int变量;
恩。 int count = 0;