When I first ran the sample HelloWorld app, it displays the hello world text on the emulator. I decided then to delete that and make a button. What I wanted is that when I click the button, it will show a text "This is the second activity". I made another XML file and another class to handle the second activity to display the text. But when I ran again, I cannot see the changes on the UI for the emulator. The text "This is the second activity" does not show after I clicked the button. I saved everything. How would I automatically update the UI of the emulator after some of the changes made on the design? I am new to android development. Please help me. Btw I cannot post images so it requires 10 reputation that's why I used online image viewing. Sorry for that.
Here is my Graphical layout on eclipse: activity_main.xml
http://s16.postimg.org/wusm4qrp1/image.png
second.xml
http://s29.postimg.org/qft17p5on/image.png
Running the emulator:
http://s28.postimg.org/f9dn32ku5/image.png
After clicking the button (in which case the text I edit does not show):
http://s16.postimg.org/75r62dodx/image.png
Because you didn't post your code, I'll try to explain it from the beginning.
I don't know if you can do it in an other way, but the following answer assumes we aim the good programming practice.
Both of the activities have their distinct layouts set in the following way, right?
public class MyFirstActivity extends Activity{
...
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_first);
...
public class MySecondActivity extends Activity{
...
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_second);
...
Then, in your first activity, define onClickListener of your button
...
setContentView(R.layout.activity_first);
Button myButton = (Button)findViewById(R.id.my_button);
myButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(MyFirstActivity.this, MySecondActivity.class);
startActivity(intent);
}
});
That being said, I don't recommend you to have two activities for this functionality. You should have different activities when you need different layouts. Putting the button and the textview in the same layout and updating textview inside the button's onclicklistener is a better solution.
Related
What I want to do:
I want to have multiple activities each prefaced with a page explaining to the user what the activity is about.
What I'm currently doing:
So my main class BaseModuleActivity extends Activity and I am trying to write a function called showTutorial() which will explain the next steps to the users.
Here is my attempt in doing so:
public void showTutorial(String title, String explanation){
setContentView(R.layout.tutorial_screen);
TextView tv1 = (TextView)findViewById(R.id.tutoTextTitle);
tv1.setText(title);
TextView tv2 = (TextView)findViewById(R.id.tutoTextExplanation);
tv2.setText(explanation);
findViewById(R.id.tutoButton).setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// Perform action on click
//remove the tutorial's view
findViewById(R.id.tutoLayout).setVisibility(View.GONE);
}
});
}
And this method is called in the following:
public class myFirstActivity extends BaseModuleActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_first);
//First show tuto
super.showTutorial(getString(R.string.upTitle),getString(R.string.upExplanation));
//TODO then actually do the activity stuff
/*
(findViewById(R.id.next_button)).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
finish();
}
});
*/
}
}
Problem:
I think the problem is mainly conceptual. I don't know the best approach to do this and the approach I'm taking is not working.
What I'm doing is not working because the view just become empty. I thought setting the visibility of the linearLayout to gone would make it disappear and the actual activity will able to take place.
What I need:
I need to understand if I can do what I want with my approach or not? Or what approach should I take.
I found some similar questions. However, the answer to these questions didn't seem to fit my problem.
I also looked into layout inflater and fragment, but layout inflater seem to be more for listView and fragment uses layout inflater.
Well, there are some approaches to show a guide for your activity (or application).
First one, and probably the easiest, is to show a dialog/TextView when user enters an activity and explain the activity guide in that dialog/TextView using plain text. From your explanation, I think this one is what your are trying to do.
Second one is to use something like slides with pictures to explain about your activity (like Google Sheets application).
Third one is to explain each control in your activity separatly by highlighting them (similar to how Go Launcher explains its feature on first launch)
You can find more info in below links:
How to implement first launch tutorial like Android Lollipop apps: Like Sheets, Slides app?
Android - first launch interactive tutorial
Seems that what you want is actually an introduction. Take a look at this project:
https://github.com/rubengees/introduction
From each introduction page you can launch the correspondent activity.
I am new to android development and am using android studio in ubuntu to write a simple Android app.
Right now the main activity activity_go is an xml file which describes the first set of objects being displayed. By adding a click listener to a button object described on activities_go.xml
I am able to change the activity to another set of objects, 'two' which corresponds with two.xml
The Following is the java code I am currently using to switch between xml files
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_go);
Button nxtButton = (Button) findViewById(R.id.nextButton);
nxtButton.setOnClickListener(new View.OnClickListener(){
public void onClick(View arg0){
setContentView(R.layout.two);
}
});
}
Upon running this I am able to display two.xml once the button is clicked.
How Can I do this again, upon clicking a button on two.xml change to three.xml ?
or is there a better method to shift between the layout xml for android applications?
I guess, you need to view trainings by Google. This article is about your case.
I am really lost here.
I have an application which uses 3 XML files which each xml file is for each tabs ( i have 3 tabs with my app), which works fine. Under one of the tab there is a button, which when I click on it , it meant to pick up the name and number from the contact application and print it in that tab's screen, which is done by connecting to database and picking up names and number after being selected from the contact app. they all work fine.
But always after the process and picking up data and setting the textview values under the tb3, the main 3 tabs are disapeared and also all the 3 diffrent XML fileas are combined together Does anyone knows why?
Does anyone knows what to do ?any tutorial ?
someone suggested Fragmentmanager but I have no idea how to use that?
Pleas, please someone help me with this.
Here is the code for main activity which shows the tabs :
public class MainActivity extends TabActivity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Resources res = getResources(); // Resource object to get Drawables
TabHost tabHost = getTabHost(); // The activity TabHost
Button addbutton = (Button) findViewById(R.id.addButton);
tabHost.addTab(tabHost.newTabSpec("tab1").setIndicator("tab1",
res.getDrawable(R.drawable.tab1)).setContent(R.id.tab1Layout));
tabHost.addTab(tabHost.newTabSpec("tab2").setIndicator("tab2",
res.getDrawable(R.drawable.tab2)).setContent(R.id.tab2Layout));
tabHost.addTab(tabHost.newTabSpec("tab3").setIndicator("tab3",
res.getDrawable(R.drawable.tab3)).setContent(R.id.tab3));
tabHost.setCurrentTab(2);
addbutton .setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent intent = new Intent(MyActivity.this,ContactsDemo.class);
MainActivity.this.startActivityForResult(intent,1);
}
});
}
}
This suppose to open myActivity and then goes back to the MainAcitiviy. But after it loads the other activity, all three tabs disappears and all the three xml files combines.
Given your information I can only assume that addButton is a Button on one of your Tabs and that you want to return to the originating tab or one of the other two. I've built a similar app and I think you have to place the startActivityForResult()-call in one of the tab-activities, since you mentioned tb3 this would be a good start. When I do a startActivity() or startActivityForResult()-call and this new activity is closed or the user hits the back-button I'm back on my tab with the tabs-ribbon visible.
Hope this helps.
I have been trying to figure this thing out with no luck in eclipse. I have created 3 screens. One being the main menu which a button leading to another button which then leads to an Activity. I can get the button from the main menu to lead onto the button onto the second screen but i can't get the second button to lead onto the third screen.
Can anybody help me?
appproject
You should really post some code so we can help you...but it seems like you need to look at your onClick() method for the second button.
Providing you have three separate Activities for each of these three screens (I'll call them ActivityA, ActivityB, and ActivityC), you'll also probably need an XML layout for each. There are ways of doing it without an XML layout, but for now just stick with that.
The next thing is you want to make sure your Button is initialized properly. ActivityB should look like:
public class ActivityB extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_b);
Button b = new (Button) findViewById(R.id.button2);
b.setOnClickListener(new OnClickListener() {
#Override
protected void onClick() {
startActivity(new Intent(this, ActivityC.class);
}
});
}
The first thing you should do is check to make sure your button functions in a way similar to how I've described here. If that doesn't change anything, make sure you are initializing your Button in accordance to how it is defined in the layout XML. You must use an id for a Button that is in the same XML layout as the one you set in setContentView(). If not, it will do nothing, no matter what you put in the onClick() method.
I hope that helps!!
Ubuntu 11.10 ADT 16.01 Java 6 Eclipse Java EE Indigo SR1 - All latest release following android dev requirements.
I am just starting to learn coding for android and got to a tutorial on switching Activities. Using the New project android template, I made another test activity class identical to the first except for name.
package com.test.SwitchActivity;
import android.app.Activity;
import android.os.Bundle;
public class SwitchActivityActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
}
The problem is that when I use the Menifest editor edit the AndroidManifest.xml file - add button for the Application Node, the listbox is empty. All the tutorials I have found are populated with xml tag choices. Now, I can add the xml data manually - it is no problem. What is driving me nuts is not being able to figure out why it does not work for me as it is supposed to work. I don't find other people having the issue and I have re-installed everything at least once before coming here to post another question.
I just want to finish the tutorial and switch between two activities.
Here is a screenshot of what I describe. Anyone have any ideas as to why it does not work?
http://i.stack.imgur.com/Fwfbz.png
To create another activity
Create a new class "myactivity.java" that extends the Activity
Create android xml file with your UI items in it lets call it exampleactivity.xml (it should be in small letters with .xml extension and should be saved in res/layout folder).
In myactivity.java add the following method (same as above except exampleactivity replaced main)
#Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.exampleactivity);
}
}
create a button changeactivity in SwitchActivityActivity and initialize it in onCreate method of SwitchActivityActivity via
changeactivity = (Button) findViewById(R.id.newActivityButton);
create the following in onCreate method of SwitchActivityActivity
changeactivity.setOnClickListener(new OnClickListener() {
Intent i;
public void onClick(View v) {
i = new Intent(Intent.ACTION_DEFAULT);
i.setClass(SwitchActivityActivity.this, myactivity.class);
startActivity(i);
}
});
In the main.xml create a button and give the button id by
android:id="#+id/newActivityButton"
Finally add the following in AndroidManifest file after the SwitchActivityActivity activity tag
compile and run it.