onClick method issue

Question

ok, so I am going through the tutorial of the \"MyFirstApp\" on the devoloper.android.com site. I am on the last tutorial and I have did everything for the first chapter you

Answer 1

I think you're getting the message from the intent the wrong way. EXTRA_MESSAGE is the content and message is the identifier.

So your code on DisplayMessageActivity.java

String message = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);

should actually be:

String message = intent.getStringExtra(message);

Answer 2

You can see in your activity_main.xml you have to declare button with onClick() this way then and then it will be work.

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Click" 
        android:onClick="sendMessage()"/>

</LinearLayout>

Answer 3

It looks like you misspelled the function name in your xml for the Button onClick(). You have an uppercase "m" in your java code

 public void sendMessage(View view) {

and probably a lowercase "m" in your xml

<Button
...
android:onClick="sendmessage"/>

To comply with java standards, change it in your xml to

 android:onClick="sendMessage"/>