Develop Reference

Start Activity in same intent

i want to know how to start all my activities in same intent. My app have a drawer activity and i want when i select any item, it will start an activity in the same intent, how can i do that ?
Main Acitivy
#Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
int id = item.getItemId();
if (id == R.id.nav_camera) {
// Handle the camera action
} else if (id == R.id.nav_gallery) {
startActivity(new Intent(MainActivity.this, Main2Activity.class));
return true;

I checked Google Drive and I'm guessing you're referring to the behavior that when you click on something only a part of the screen updates. You can easily implement this by using Fragments. I cannot explain it to you in detail but this is a developer.google link that will help you get started. https://developer.android.com/training/basics/fragments/index.html

navigation view android not triggered onOptionsItemSelected on R.id.home

I have created the navigation drawer activity from android studio and in the method onOptionsItemSelected i'm trying to catch the click of the hamburger icon but it doesn't work.
The only thing i changed is this:
#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 == android.R.id.home) {
Log.w("ACTIVITY","home pressed");
return true;
}
return super.onOptionsItemSelected(item);
}

Back button behavior on an Activity

I have a problem in my app. I have a MainActivity with Fragments, each Fragment have a list with a recyclerView. When I click an Item of the list, the app goes to a new DetailActivity.
In the DetailActivity I have the next code line:
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
When I click the back button in the ActionBar I return to the MainActivity in another fragment, not the one I clicked the item.
Thanks!

As stated by #kareem adel make sure you are not ending the previous activity. Dont use Flag_activity_clear_task or flag_activity_new_task
If that doesn't help you could just tell the back button where to go.
With getSupportActionBar().setDisplayHomeAsUpEnabled(true); set you can do this:
#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;
}
else if(id == android.R.id.home){
//Back button was hit so go somewhere.
Intent i= new Intent(this, MainActivity.class);
i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK); //Clear previous Activities
startActivity(i);
finish(); //End this activity.
return true;
}
return super.onOptionsItemSelected(item);
}

Action bar on Action back (Navigation Up) to custom activity?

I have many activities in my application
in that I have Given this
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
actionBar.setDisplayHomeAsUpEnabled(true);
}
to Go back to Home Page from other activities
like Below
If I press those three buttons all menus are working
this is my Option menu
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.abc) {
Intent mypIntent = new Intent(this, abc.class);
startActivity(mypIntent);
return true;
}
else if (id == R.id.web) {
Intent webIntent = new Intent(this, Web.class);
startActivity(webIntent);
return true;
}
else if (id == R.id.about) {
Intent aboutIntent = new Intent(this, About.class);
startActivity(aboutIntent);
return true;
}
.
.
.
..
return super.onOptionsItemSelected(item);
}
Here There is no menu named id == R.id.login or id == R.id.home but its going to login few days back its gone to home activity
but If I press Back.. action back is redirect to Login page Inst-ed of Home
I have added a Login page for my application using shared preferences.. and it is now launcher activity..
Here In my Login activity on if once user is sign in it should it should redirect to Home activity on every time..
and its working fine..
But on action bar when I press arrow button it is redirecting to empty login page..
if I press cancel entire app is working .. my credentials are safe except this action bar..
Update
I have Given Intent also if Login credentials success redirect to Home activity on app start up it will check every time
every thing is as for fine except action back
how to fix this...

Alright make sure u do declare activities as below -
<activity
android:name="com.example.myfirstapp.DisplayMessageActivity"
android:parentActivityName="com.example.myfirstapp.MainActivity" >
<!-- The meta-data element is needed for versions lower than 4.1 -->
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.example.myfirstapp.MainActivity" />
</activity>
Now in every activity add below code block-
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
// Respond to the action bar's Up/Home button
case android.R.id.home:
NavUtils.navigateUpFromSameTask(this);
return true;
}
return super.onOptionsItemSelected(item);
}
Update
add a New class file to check login or not else use home as default.. and replace your new class as launcher in Manifest

Just override this method.
#Override
public boolean onOptionsItemSelected(MenuItem item)
{
switch (item.getItemId())
{
case android.R.id.home:
{
Intent intent = new Intent(mContext, Activity.class);/*your activity name*/
startActivity(intent);
}
default:
return super.onOptionsItemSelected(item);
}
}

Evaluating R.id.home

I was following this tutorial here - http://developer.android.com/training/implementing-navigation/ancestral.html - for implementing the Up Navigation. Sort of the same as the user pressing the Back button on the phone, but the onBackPressed() method does not fire when the 'Up' button is pressed. In the tutorial they show that you trap R.id.home in the onOptionsItemSelected() method. This web page - http://developer.android.com/reference/android/R.id.html - shows that the value of R.id.home should equal 16908332, but it doesn't in my app. In the code below if I use R.id.home it fails. If I hard-code in 16908332 it works. For me R.id.home evaluates to 21312330724. According to the page, all of the R.id values begin 1690. I hate hard-coding in a value for a built-in value, but I'm not sure what else to do. Could this cause problems down the road? Am I doing something wrong? Is this a bug?
Greg
#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;
}
//noinspection SimplifiableIfStatement
if (id == R.id.home) {//16908332
Intent upIntent = NavUtils.getParentActivityIntent(this);
upIntent.putExtra(CAT_ID, CatID);
upIntent.putExtra(USER_ID, UserID);
upIntent.putExtra(LIST_ID, ListID);
setResult(RESULT_OK, upIntent);
NavUtils.navigateUpTo(this, upIntent);
return true;
}
return super.onOptionsItemSelected(item);
}

You need to compare it to the android one:
if (id == android.R.id.home){
...
}