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Android menu crashs application

I have the following in my code and I want to switch to this new activity when I select it from the menu, but the app just keeps closing:
public boolean onOptionsItemSelected(MenuItem item) {
// Handle item selection
switch (item.getItemId()) {
case R.id.mi_baas:
startActivity(new Intent("com.my.project.BAAS"));
return true;
default:
return super.onOptionsItemSelected(item);
}
}
}
Please help, 2 days so far.....

You have to pass context and class which is to be opened.
Your code should be like this.
public boolean onOptionsItemSelected(MenuItem item) {
// Handle item selection
switch (item.getItemId()) {
case R.id.mi_baas:
startActivity(new Intent(getContext(),BAAS.class));
return true;
default:
return super.onOptionsItemSelected(item);
}
}
}
Hope it helps:)

OnBackBressed not called

I have activity ActivityProfile, have getSupportActionBar().setDisplayHomeAsUpEnabled(true); implemented, onBackPressed() as well, search all over the internet and still no help.
#Override
public void onBackPressed() {
Toast.makeText(this, "OnBackpressed fired", Toast.LENGTH_SHORT).show();
super.onBackPressed();
}
#Override
public boolean onKeyDown(int keyCode, KeyEvent event)
{
//replaces the default 'Back' button action
if(keyCode== KeyEvent.KEYCODE_BACK) {
// something here
onBackPressed();
}
return true;
}
using the device's back button works, but not on the app...

To implement Up navigation, declare a parent of that particular activity in manifest and setDisplayHomeAsUpEnabled as true.
<activity
android:name="com.example.myfirstapp.DisplayMessageActivity"
android:label="#string/title_activity_display_message"
android:parentActivityName="com.example.myfirstapp.MainActivity" >
<!-- Parent activity meta-data to support 4.0 and lower -->
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.example.myfirstapp.MainActivity" />
</activity>
Read More https://developer.android.com/training/implementing-navigation/ancestral.html

you should use onOptionItemSelected to handle click on the bottom on action bar :
#Override
public boolean onOptionsItemSelected(MenuItem item)
{
switch (item.getItemId())
{
case android.R.id.home:
finish();
return true;
default:
return super.onOptionsItemSelected(item);
}
}

Try this
setSupportActionBar(toolbar);
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
onBackPressed();
}
});

This should work
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
onBackPressed();
}
return super.onOptionsItemSelected(item);
}

hi add this code in your activity. when you press back button in toolbar following code execute.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.your_view);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setHomeButtonEnabled(true);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()){
case android.R.id.home:
finish();
break;
default:
return super.onOptionsItemSelected(item);
}
return super.onOptionsItemSelected(item);
}

How to go back to previous activite(s)?

so i have Activity A,B, and C. Activity A & B both go to activity C. When i am on activity C and I press the back home button on mySupportActionBar, I want to return to the state of activity (from the state i left it in) I came from. How would i accomplish this?
Here is my onOptionsItemSelected(). So currently, it goes back to the designated parent activity i assigned in manifest to avoid my app from crashing. Because the parent activites require strings from intents.
#Override
public boolean onOptionsItemSelected(MenuItem item)
{
int id = item.getItemId();
if(id == android.R.id.home)
{
NavUtils.navigateUpFromSameTask(this);
}
return super.onOptionsItemSelected(item);
}
I would also love to accomplish this onBackPressed().

The back arrow button is the "home" button when you're in a inner activity so you could finish the inner activity or maybe just call the back button
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
onBackPressed();
return true;
default:
return super.onOptionsItemSelected(item);
}
}

Use android.R.id.home
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
finish();
return true;
default:
return super.onOptionsItemSelected(item);
}
}

You also can use setNavigationOnClickListener on toolbar to trigger back button.
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_filter_category);
setSupportActionBar(toolbar);
if (getSupportActionBar() != null) {
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setDisplayShowTitleEnabled(false);
//back button action
toolbar.setNavigationOnClickListener(view -> finish());
}
}

How to make home button act as back button?

I have two activities.One of them has Fragment.
From this fragment I can go to another activity, but by clicking the button "home" it goes to previous activity instead of going to the fragment of the previous activity.
Image
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_closet);
getSupportActionBar().setHomeButtonEnabled(true);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
}

Refere below code :
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
finish();
return true;
default:
return super.onOptionsItemSelected(item);
}
}

You need to override below method :
#Override
public boolean onOptionsItemSelected(MenuItem item) {
if (item.getItemId()== android.R.id.home) {
finish();
return true;
}
return false;
}

getSupportActionBar().setNavigationOnClickListener(new OnClickListener {
public void onClick(View v){
onBackPressed()
}
})

Since you want same behavior as of back button you should use onBackPressed();
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
onBackPressed();
return true;
default:
return super.onOptionsItemSelected(item);
}
}

why it don't work when I click back arrow icon?

I set the following code in my activity:
ActionBar actionBar = getActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);
#Override
public boolean onOptionsItemSelected(MenuItem item) {
return super.onOptionsItemSelected(item);
}
Why it can't work, when i click back arrow icon?

You need implement it by yourself：
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
finish();
break;
default:
break;
}
return super.onOptionsItemSelected(item);
}