I use eclipse for android development, and I find it very annoying that every time I create an activity or add new views to my activity, I need to create the references to views in my layout. I am looking for some kind of eclipse plugin that can generate the calls to findViewById() from the layout. I couldn't really find anything because I didn't know what it would be named. It would be very useful and time saving if that kind of plugin existed.
EDIT: The answers you gave are great. Can these tools also add more references to an existing activity so I don't have to manually do that when I add a view to the layout?
You can use https://github.com/JakeWharton/butterknife library for View Injections.
You can also get eclipse plugin https://marketplace.eclipse.org/content/lazy-android for the same.
But the ButterKnife library is frequently being contributed by android devs than the mentioned eclipse plugin. With this library, you can also avoid instantiating listeners yourself by just using like,
#OnClick(R.id.submit) void submit() {
// TODO call server...
}
For View injections, simply,
#InjectView(R.id.user) EditText username;
#InjectView(R.id.pass) EditText password;
So, it will compile as,
username = (EditText) findViewById(R.id.user);
password = (EditText) findViewById(R.id.pass);
Try the morcinek code generator. Its really simple to use.
This are the steps to install the plugin:
http://tmorcinek.wordpress.com/2011/11/30/eclipse-plugin-for-automatic-generation-of-activity-code-from-xml-layout-file/
After install process you may want to configurate a package to get the classes built by the generator, on the IDE -> Window -> Preferences on Bookmark Android Code Generator you can change that parameter.
The plugin does need a better interface for custom activities, still you could get the code, its really simple to make the changes you need, at least the inline listeners.
This solution doesnt work to modify classes you already have, that would be a really good improvement... i'll give it a try in a couple days with more time.
Related
I'm new to android studio and I'm leaning it from this video
At 50:45 he says that we can directly use the id without findViewById (), for him it shows just import that Id, but when I tried the same I'm not getting what he is getting. Can anyone tell me what's wrong, is that feature removed in the latest update??
"kotlinx.android.synthetic is no longer a recommended practice. Removing in favour of explicit findViewById"
So, this feature`s been deprecated almost a year ago.
The new recommended way of working with view tree is View Binding.
Or you could write some lazy extension function that uses findViewById under the hood.
You can use the Kotlin Android Extensions check here or with the help of data binding or view binding you can just use the id directly in to your java activity class
The way you're talking about is Kotline Extensions for view, for which you apply it in the build.gradle file using apply plugin: 'kotlin-android-extensions', sync the project as prompted by the Android studio and it starts working.
But, Kotlin extensions has also been deprecated for view binding which is null-safe, also easy to implement and better.
To read about view binding, read the Android documentation on ViewBinding here and about migrating here. You can also go with this article to help with setting up Android view binding.
I am using MVVM android architecture for my application.
I want to implement click event, so, do we need to use data binding architecture components or we can just use activity for handling the click event and validating the user inputs?
What's the best way to implement this?
Well the question would be using the Databinding or not. Here are some pros and cons of Databinding:
Pros:
Makes the code super clean.
Makes the code shorter.
Easy to test.
Cons:
Sometimes it's hard to debug.
It's a little heavy and increases the compile time.
But... since Google has already anounced it as part of the Android Architecture components I believe you should use it.
What's the best way to implement this?
I don't know how familiar you are with the Databinding but you should know something about Binding Adapters, anw in the onClick you won't be needing it. Just add the android:onClick attribute in the XML file. Also you can find this Codelab to properly implement it:
https://codelabs.developers.google.com/codelabs/android-databinding/#0
Example:
First of all make sure you have the Databinding enabled in your build.gradle
android {
...
dataBinding {
enabled true
}
}
After that go to the layout you will use the databinding (and for that make sure it will be an Activity/Fragment), and just type ALT+ TAB in your IDE and than....
After that, define types, for example a ViewModel and it's name. And in the view that will use the click function add what I said above. (android:onClick="#{() -> viewmodel.onLike()}")
You are not finished. You will somehow need to connect your logic to that databinding, so go to your Java/Kotlin code for your Activity/Fragment and:
Replace the setContentView(R.layout.some_activity) with val binding : SomeActivityBinding =
DataBindingUtil.setContentView(this, R.layout.some_activity)
Notice the SomeActivityBinding will be provided by the IDE itself because is handled on the Databinding library according to the xml naming.
That's the most basic. Good luck.
Maybe this question has been ask already, but could not find any answer for almost 2hours of internet search.
There is a graphical UI designer wich is coming along with the last android SDK.
Looks pretty cool and well done.
Nevertheless I * cannot find how to attach an event to the control through the graphical editor.
Of course I can add it manually into the xml, but in that case, what's the purpose of having such tool without that function ?
I mean all the other SDK I had in other languages always include that function.
I've also not been able to find doc about how to use this tool. Quite sad...
Thanks
If you want to add a click event handler, select the button (widget) in the GUI that you want to listen for, and look for the property onClick. Enter the name of the method you want to call when the user clicks on that widget, like.. onMyButtonClick
Then add the method to your Activity
public void onMyButtonClick(View v) {
// I heard the button click
}
The GUI builder is getting there, and is not yet as easy to use as the one in XCode, but it's not hard when you get used to it.
I've been working on the 'Tip Calculator' app for Android and I have a couple of questions.
I'm supposed to (in the process of creating the GUI) use some EditTexts to allow the user to enter the bill amount and read the calculated total bill. In the version I have, there is no EditText anywhere in the Visual Layout Editor, only CheckText. Are these the same?
Whenever I try to edit the Java code for the app, as per the book I have, I keep getting the message:
Thus and such is never used
For example, with
private static final String BILL_TOTAL = "BILL_TOTAL';
or anything from the import Android list, other than the one referring to a bundle. I'm Not sure how to resolve this. I have some experience with C and C++, but Java is new to me.
The warning that tells you that a variable or method or import is not used can be ignored, especially if you just haven't gotten to using it yet. It's a warning and not an error, so your app should compile regardless.
I don't know what you're using to build your layout (eclipse? I use Intellij Idea), but to add an EditText, you can edit the layout file by hand. Add a line similar to:
<EditText android:id="#+id/myEditText android:width="FILL_PARENT" android:height="WRAP_CONTENT"/>
As a general rule, I like to edit these things by hand. Then, when something breaks or doesn't work as I expect it to, I have some grasp of what's in there, and so I can usually fix it. The value gained by learning how to create a layout by hand easily offsets the value of the time that you'll save.
Good luck.
I'm attempting to create an Activity and unfortunately every time I want to grab one of my XML components it gives me a RunTimeException (NullPointer).
Anytime I use code such as:
TextView tv = (TextView) findViewById(R.id.myView); //I get the exception
The same happens for any components I attempt to find with that method. I can't quite figure out why. I know it isn't due to the Activity not being in the Manifest because it's the only Activity in the test app I made. (The one set up by default).
Oddly I can still use setContentView(R.id.myView). It just doesn't seem to want to find anything when using the findViewById method.
Info that might be of use:
I am currently using NetBeans as my IDE.
I have done multiple 'clean and builds' as was suggested in another question. Android -findViewById question
Has anyone run into this issue before? If so, what was the solution?
If need be, I can provide sample code of when this is happening.
Don't pass in a view ID to setContentView, pass in a layout resource ID:
setContentView(R.layout.layout_name);
If you still have problems, post your layout file.
It is very sure that you R.java is not properly generated.
Delete R.Java in netbeans IDE and Re-build the project.
Hope it resolves your query.