I have looked everywhere but don't seem to be able to find what I am looking for. I have an activity with multiple buttons, each button opens a new activity with an identical recyclerview layout, but different data. I am wondering if it is possible to use one activity and layout instead of multiple? this way instead of having 10+ activities (one for each button) I only have to manage one when a button is clicked and simply pass the necessary list data to it.
I believe you could set the intents for each button to call the same activity but with an integer such as 1-10, in the activity it takes the value and decides which list should be presented? If anyone thinks of how this could be done or a simpler way I would greatly appreciate it!
Yes, there are various ways to do that.
You could use multiple fragments on the same activity. Then add/remove fragments on each button click.
You can have multiple layouts within your activity. Say you have two buttons, and you have three layouts layout1, layout2, layout3, sequentially one after the another. So if initially, layout1 is visible and the rest are gone using layout.setVisiblity(View.GONE), if you click button1, ypu can do layout1.setVisiblity(View.GONE); layout3.setVisiblity(View.GONE); layout2.setVisiblity(View.VISIBLE) and vice-versa for pressing button2.
Are all the activities opened by the buttons similar? If so, you could only take care of the changes in the elements of the layout & specify conditions.
For instance, if you click a button, instead of changing the whole thing, you only go into the buttons & change their texts with btn.setText("..."). You could define different conditional statements inside the onClickListener of that button.
It could be something like:
if(btn.getText().equals("a certain text that you set to the button")){
doSomething();
else if(btn.getText().equals("another option")){
doSomethingElse();
Following this logic, you could continually update the elements in your layout & your code will decide what to do depending on what's stored in these elements.
The second option that comes to my mind would be creating different xml layout files & simply changing the layout of your MainActivity to the appropriate one depending on what stage of your process you are at.
I hope this helps,
Related
I was thinking about using spinners (as it is like a dropdown feature) to change the type of text on my activity. For example let us say we choose the car from the spinner, it would change/replace the layout completely and show the car attributes e.g. car make. Another example is if the user click "Mobile" the spinners will change the layout on the activity.
Is this a good approach to take? Or is it best to create a activity for each product? The only reason I asked this as one of the answers here recommended its not a good idea.
You are the only one that can decide whether to do that or not which mainly depends on the amount of changes that you will make to your layout events handling, and about spinner it has nothing to do with this manner, you will have to do an action after choosing an item from the spinner either creating a new intent() and launching an activity or changing the layout.
So, if you have minor changes in your "layout events handling", you have two options:
if the layout changes mainly in sources, backgrounds, and
visibility of the layout-elements but the structure remains as it is, your best choice is to just make your changes to the views(elements)
itself without changing the whole layout.
if the layout structure has to be changed, you are advised to change
the whole layout by using the method:
setContentView(R.layout.new_layout);
and after that you have to
declare the layout elements again.
BUT, if you have a complete new layout for every element in the spinner, you have two options:
create an activity for each element of the spinner, and include the spinner in each activity of them.
create a fragment activity, and include the spinner in the main
layout of the activity, and create a fragment for each element in
the spinner, and with each element change, navigate to it's
corresponding fragment.
I have a dynamic UI that I need to generate and I would like to know what the best approach would be to do this and why? The application that I need to make will either way only have a single activity in which to display various different views which are generated by code, so not in an XML file.
So basically I want to draw one set of views and have a user interact with them (textview, button, radio button, edittexts etc). Then save the data he generated, clear the canvas or screen and within the same activity generate the next set of views for the user to interact with.
I have done extensive research and I know that I can use either a Fragment or an Activity with a LinearLayout to achieve this, but I am not sure which would be better and why?
Thanks,
Wihan
is using setContentView multiple times bad while changing layouts?
Some people say that it's bad and they never say why.
and is there some other thing to change layout using button?
Let's take a look at the Android Documents:
Set the activity content to an explicit view. This view is placed directly into the activity's view hierarchy.
So, setContentView will overwrite the layout, and replace it with a new one. Usually, you only want to do this once in onCreate. Theoretically, you could do it more, but it involves re-drawing the entire layout, and this could take some time. There are a few alternatives, depending on exactly what you want:
ViewAnimator: This is useful for showing a quick animation, if you want to change the view multiple times in quick succession.
Fragments- Instead of re-drawing the entire view, you can switch out fragments. Each fragment is a kind of mini activity, and overall this will contain the code much better.
Pass Intent Arguments- Pass information to an activity to help it set up. The first activity passes information to a common second activity, which knows how to set itself up based off of the information it receives from the first activity.
As for your specific application, here's what I would do:
Each band follows a specific layout. There is only 1, or maybe a few, possible layouts.
When the Band activity starts, the appropriate layout is chosen, and populated, knowing what's in there.
The Android SDK shows how to pass data from one activity to another. Just pass the data that the second activity needs from the first, using something like this:
Intent intent=new Intent(...);
intent.putExtra("Album","Some Album")
startActivity(intent);
The second activity will do this:
Intent intent=getIntent();
String albumName=intent.getExtraString("Album");
//Does something with albumName, maybe get a TextView and .setText()
Yes this is bad, because it inflates your activity with your layout, and if your layout has a lot of views, it may take time.
To avoid that you should use a ViewAnimator, where you put all your layouts and you switch by showNext() and showPrevious(), i.e:
<ViewAnimator xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/ViewAnimator"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<RelativeLayout> </RelativeLayout>
<RelativeLayout> </RelativeLayout>
</ViewAnimator>
And in your code:
// Don't forget the setContentView
//
// Load the ViewAnimator and display the first layout
ViewAnimator va = (ViewAnimator) findViewById(R.id.ViewAnimator);
// Switch to the second layout
va.showNext();
// Add another layout at the third position
LinearLayout fooLayout = new LinearLayout(this);
va.addView(fooLayout, 3, new ViewGroup.LayoutParams(MATCH_PARENT, MATCH_PARENT));
i cant show example because i'm waiting for answer to do it. okay i
have the app of lyrics(it will show lyrics of band) and albums are new
activities but i dont want many activities and thats why i want to
make songs only layouts and change views with button press
It sounds like you're going about this the wrong way. If you want to change the UI an Activity contains, then Fragments would be the better approach. There's a bit of a learning curve there, but it's good android design, and well documented.
Further, you seem to be confusing formatting and content. If you're displaying song lyrics, you don't need a new layout for each song. You just need to change the lyrics and keep them in the same activity. What you're doing is akin to creating a new web-browser for each web-page you intend to visit. Instead, find a way to store the lyrics and display them on a single activity (or in a fragment) to display those lyrics. The same would apply to each album: One activity would display the album cover in the corner (or as background), the title, release date, etc, as text, and then a list of songs below. The actual content of the TextViews can change, but the layout ought to be the same.
Let's say i have the Android XML file home_page.xml.
on this home_page.xml i have some variations that i want to show at different activities, and i'd like to reuse the same main layout home_page.xml.
For example, imagine variations on the page such as:
there's 2 more buttons if the user is in state A
there's 1 more editText field if the user is in state B (same activity as state A)
there's a different arrangement of layout on the Z-axis in a frame layout if the user is in state C (same activity as state A)
i know it's possible to programmatically say hide views and set views as visible. but is there a better way to do this via xml or something?
Android recommends using 2 Tags for re-using the layouts across different screens.
Include
When to Use ?
If you already know the layout that you want to re-use, create a new XML file and define the layout. Use tag to re-use it.
Merge
When to Use ?
To eliminate redundant view groups in your view hierarchy when including one layout within another, we can use tag.
Refer to this link - http://developer.android.com/training/improving-layouts/reusing-layouts.html for code sample and more details.
You can hide views but using the Visibility flag.
View v = findViewById(R.Id.my_view);
v.setVisiblity(View.GONE); //etc.
I've tried stuff like this before. I had mixed results. This is fine if you are doing things, like asking the user for a name, then showing an address input or something. But if you find yourself with like 3 or 4 conditions for one editText and then different ones for a button in the same class you might want to just use different layouts. A lot easier to manage.
Can I choose different layout for the Fragment based on the Button that has been clicked on the Activity, or should I create one Fragment class for each Button?
I know that Fragments exist to accommodate different UI but in my case I have many buttons that on click display a FrameLayout and I was thinking if it is possible to save time from copy/paste ?
I'd say that depends on how your layouts/fragments look like. If they are huge and very similar it could be better to have one layout. You could also think about using <merge /> or <include/> in that case.
This way you can maintain equal parts in (sub-)layouts without the need of code repetition.
Have a look at Googles site here.