Difference between revisions of "First steps"
From MyWiki
(3 intermediate revisions by the same user not shown) | |||
Line 12: | Line 12: | ||
}<br> | }<br> | ||
in oncreate<br> | in oncreate<br> | ||
− | + | Button buttonblue;<br> | |
buttonBlue = (Button) findViewById(R.id.button_blueinvisible);<br> | buttonBlue = (Button) findViewById(R.id.button_blueinvisible);<br> | ||
define button in main activity<br> | define button in main activity<br> | ||
if ( v.equlas(buttonblue)) then do the stuff<br> | if ( v.equlas(buttonblue)) then do the stuff<br> | ||
− | Toast.makeText(getApplicationcontext(), "asdfadsfa", Toast.LENGTH_SHORT.show()) | + | Toast.makeText(getApplicationcontext(), "asdfadsfa", Toast.LENGTH_SHORT).show();<br> |
+ | |||
+ | Below is the code from the coursera site <br> | ||
+ | <source lang="java"> | ||
+ | package fr.centralesupelec.galtier.block01; | ||
+ | |||
+ | import android.support.v7.app.AppCompatActivity; | ||
+ | import android.os.Bundle; | ||
+ | import android.view.View; | ||
+ | import android.widget.Button; | ||
+ | import android.widget.Toast; | ||
+ | |||
+ | public class MainActivity extends AppCompatActivity { | ||
+ | |||
+ | // the 2 buttons defined in the activity_main.xml file | ||
+ | Button buttonBlue, buttonPink; | ||
+ | |||
+ | @Override | ||
+ | protected void onCreate(Bundle savedInstanceState) { | ||
+ | super.onCreate(savedInstanceState); | ||
+ | |||
+ | // display the GUI defined in the activity_main.xml file | ||
+ | setContentView(R.layout.activity_main); | ||
+ | |||
+ | // retrieve references to the Views defined in the activity_main.xml | ||
+ | buttonBlue = (Button) findViewById(R.id.button_blueInvisible); | ||
+ | buttonPink = (Button) findViewById(R.id.button_pinkPanther); | ||
+ | } | ||
+ | |||
+ | /** | ||
+ | * called when a button from activity_main.xml is clicked | ||
+ | * @param v the View which triggered the method call: should refer to buttonBlue or buttonPink | ||
+ | */ | ||
+ | public void toDo(View v) { | ||
+ | if (v.equals(buttonBlue)) | ||
+ | // buttonBlue was clicked | ||
+ | // turn the button invisible | ||
+ | v.setVisibility(View.INVISIBLE); | ||
+ | if (v.equals(buttonPink)) | ||
+ | // buttonPink was clicked | ||
+ | // display a pop-up message for a short duration | ||
+ | Toast.makeText(getApplicationContext(), | ||
+ | "to do to do to do...", | ||
+ | Toast.LENGTH_SHORT).show(); | ||
+ | } | ||
+ | } | ||
+ | |||
+ | </source> | ||
+ | Below is the XML code | ||
+ | <source lang = "XML"> | ||
+ | <?xml version="1.0" encoding="utf-8"?> | ||
+ | <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" | ||
+ | xmlns:tools="http://schemas.android.com/tools" | ||
+ | android:layout_width="match_parent" | ||
+ | android:layout_height="match_parent" | ||
+ | android:paddingBottom="@dimen/activity_vertical_margin" | ||
+ | android:paddingLeft="@dimen/activity_horizontal_margin" | ||
+ | android:paddingRight="@dimen/activity_horizontal_margin" | ||
+ | android:paddingTop="@dimen/activity_vertical_margin" | ||
+ | tools:context="fr.centralesupelec.galtier.block01.MainActivity"> | ||
+ | |||
+ | <Button | ||
+ | android:layout_width="match_parent" | ||
+ | android:layout_height="wrap_content" | ||
+ | android:text="The Invisible Man's To Do List" | ||
+ | android:id="@+id/button_blueInvisible" | ||
+ | android:layout_alignParentTop="true" | ||
+ | android:layout_alignParentLeft="true" | ||
+ | android:layout_alignParentStart="true" | ||
+ | android:background="#AED2FF" | ||
+ | android:onClick="toDo" /> | ||
+ | |||
+ | <Button | ||
+ | android:layout_width="match_parent" | ||
+ | android:layout_height="wrap_content" | ||
+ | android:text="The Pink Panther's To Do List" | ||
+ | android:id="@+id/button_pinkPanther" | ||
+ | android:layout_below="@id/button_blueInvisible" | ||
+ | android:layout_alignParentLeft="true" | ||
+ | android:layout_alignParentStart="true" | ||
+ | android:background="#FD9BF3" | ||
+ | android:onClick="toDo" /> | ||
+ | |||
+ | </RelativeLayout> | ||
+ | |||
+ | |||
+ | </source> |
Latest revision as of 12:07, 5 October 2017
Simple first program
1. choose empty activity
2. we will edit activity_main.xml and MainActivity.java
3. use api level 16
4. Get rid of "hello world"
5. Drag button
6 width = match parent, change background colour
7 changethe id of the button and also the text
8 onclick property, speccify the name of method
9. public void toDo(View v){
}
in oncreate
Button buttonblue;
buttonBlue = (Button) findViewById(R.id.button_blueinvisible);
define button in main activity
if ( v.equlas(buttonblue)) then do the stuff
Toast.makeText(getApplicationcontext(), "asdfadsfa", Toast.LENGTH_SHORT).show();
Below is the code from the coursera site
package fr.centralesupelec.galtier.block01; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.Toast; public class MainActivity extends AppCompatActivity { // the 2 buttons defined in the activity_main.xml file Button buttonBlue, buttonPink; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // display the GUI defined in the activity_main.xml file setContentView(R.layout.activity_main); // retrieve references to the Views defined in the activity_main.xml buttonBlue = (Button) findViewById(R.id.button_blueInvisible); buttonPink = (Button) findViewById(R.id.button_pinkPanther); } /** * called when a button from activity_main.xml is clicked * @param v the View which triggered the method call: should refer to buttonBlue or buttonPink */ public void toDo(View v) { if (v.equals(buttonBlue)) // buttonBlue was clicked // turn the button invisible v.setVisibility(View.INVISIBLE); if (v.equals(buttonPink)) // buttonPink was clicked // display a pop-up message for a short duration Toast.makeText(getApplicationContext(), "to do to do to do...", Toast.LENGTH_SHORT).show(); } }
Below is the XML code
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" tools:context="fr.centralesupelec.galtier.block01.MainActivity"> <Button android:layout_width="match_parent" android:layout_height="wrap_content" android:text="The Invisible Man's To Do List" android:id="@+id/button_blueInvisible" android:layout_alignParentTop="true" android:layout_alignParentLeft="true" android:layout_alignParentStart="true" android:background="#AED2FF" android:onClick="toDo" /> <Button android:layout_width="match_parent" android:layout_height="wrap_content" android:text="The Pink Panther's To Do List" android:id="@+id/button_pinkPanther" android:layout_below="@id/button_blueInvisible" android:layout_alignParentLeft="true" android:layout_alignParentStart="true" android:background="#FD9BF3" android:onClick="toDo" /> </RelativeLayout>