I got this error message on my android projects after upgrading eclipse and android sdk manager. But it probably not the thing that makes this problem. So i explored about this problem on google and found the solution, at least this is work for my eclipse.
I am using windows Vista, here are my step to solve debug certificate expired android problem :
- Delete debug.keystore on C:\Users\{USER_PROFILE}\.android folder. For others operating system, you could check the path on eclipse. Please open menu Preferences – Android – Build – Default debug keystore.
- On eclipse, Clean the projects ( Menu Projects > Clean ). You probably need to restart your eclipse.
I figure out this problem are because the certificate is expired. I wondering if this debug keystore is same as keystore that i create when i installing the Android SDK. I don’t know, but eclipse can generate it. It seem the certificate is expired in 365 days. I hope this article can help to solve this problem.
Sometime we need to pass data or parameter to another Activity on Android. Only one activity is active at once. An activity open new activity for result and opened activity need parameter to set their interface or another option based on request. So it is important a system can handle sending and retrieve parameter between two Activity.
To open an activity and wait for a result, we can use this sintax
Intent newIntent = new Intent(this.getApplicationContext(), ActivityClass2.class);
startActivityForResult(newIntent, 0);
ActivityClass2 is the class name of activity that we need to create and then open it from current activity. startActivityForResult is a method to run newActivity. Later we can have the result by add this function on current Activity (more…)
You can use any text editor to write a java code for android, and then compile using JDK tools. Create android package (APK) using android sdk tools and then install and run application on emulator. But we need a tool to automatic all android development process. One android IDE that commonly used by android developer is eclipse. Using eclipse you can have an integrated development environment for android through Android plugin, such as
- write or code java source for android application
- good overview for your project inside project manager
- user friendly interface to create new android project
- compile and debugging is as easy as desktop application development
- nice java source code editor with high text editing functionality for developer
- setting emulator also easy with good overview using DDMS perspective
- run android application inside emulator with simple click
There are many more advantage using eclipse as your IDE for android. Believe me it makes you enjoy coding android with their nice interface and automatic process.
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For whom that doesn’t know yet the android, it is a new platform that basically run on gphone mobile device. GPhone stand for Google Phone, i think google want to spread their business to mobile device technology. But android is not for gphone only, at least nokia will have android on their device in future. So for developer it is a good market to make an application run on android platform. Best thing is android give developer a software development kit (SDK) that based on java programming language. And this SDK is open to all developer and has big community. This article is about installing android sdk on your windows machine.
First of all you need a java library installed on your machine. It can be a JRE or JDK, but i suggest you to install JDK as we want to develop a java application on our machine.
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I have been confusing about this problem when doing a project using google map. I believe some of you have this problem also. The problem is simple about a findViewById function on Activity or View always returning Null value. I have the following code on my layout
<?xml version=”1.0″ encoding=”utf-8″?>
<RelativeLayout xmlns:android=”http://schemas.android.com/apk/res/android”
android:layout_width=”fill_parent”
android:layout_height=”fill_parent”>
<com.google.android.maps.MapView
android:id=”@+id/mapView”
android:layout_width=”fill_parent”
android:layout_height=”fill_parent”
android:enabled=”true”
android:clickable=”true”
android:apiKey=”0QGdlm3NNz0KF5zSUTn5FvObCU2EUn7Dim25Sjw”
/>
<Button id=”@+id/btnViewPOI”
android:layout_width=”wrap_content”
android:layout_height=”wrap_content”
android:layout_alignParentBottom=”true”
android:layout_alignParentRight=”true”
android:visibility=”visible”
android:text=”List” />
</RelativeLayout>
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