OK. 1
So at this point we have a plain Hello World app. 2
So say we want to run this app. 3
All we need to do is click on play here. 4
Here you will see all the emulators that are available, if you click on run you will see the app running 5
on the emulator let's give it some time to run. 6
OK so here you can see the hello world app that was created out of the box so next we're going to look 7
at UI elements. UI is not always important for reverse engineering. 8
However there is the aspect of event handlers that might be of interest to us. 9
So for example when you click on a button what is actually happening in the code 10
Within the code, 11
is there any reference to say in edit text within the user interface so for this we're going to create 12
a simple button and an edit. 13
Text and attach some code to them. 14
OK. 15
So in the resources, layout, main activity we can see the layout that is associated with the main activity. 16
Actually if we go to our main activity we can see the layout we are referring to now in the layout. 17
We have two views the design view, which is drag and drop. 18
Then we have the text view which is the version of that UI. In the XML, 19
you can for example add a text to view by copying and pasting the existing one. 20
For example if we add more characters to the copied one we see that there are two text abuse behind 21
each other. 22
We do not need to go too deep into this but let's just add a button and an edit text for now. 23
So first of all in the view you can set it to only see the blueprint. 24
Then you can zoom in and out by scrolling in and out with control pressed or just by clicking on the 25
zoom buttons OK. 26
Let's drop in edit text and a button, if we would have to run this as it is you will see a few inconsistencies. 27
So let's run. 28
Here you can see they are on top of each other. 29
This is because we need to configure the constraints. 30
Again this is not too important but let's just make a simple constraint. 31
So first thing we're going to add a top inside constraint for the edit text. 32
Right now there is a zero default margin. 33
Let's change this to 16. 34
Next we're going to tell the button to relate it's position based on the edit text physician to do this. 35
We're going to right click on the button and do show baseline click on the button and link the baselines 36
also from the left side. 37
We're going to create a left constraint linking the button to the edit text. 38
Now if we run the app again you'll see the edit text on the left with the button on its side.