intent的一个应用activity的跳转！

其实Intent的应用很广，今天我把前两天学的Intent的一个应用共享一下，很容易。

基本步骤就是

Intent intent = new Intent();//新建一个activity
intent.setClass(TestActivity.this, login.class);//从本类的activity跳转到目标activity。
startActivity(intent);//执行目标activity

TestActivity.this.finish();//退出第一个activity

注：还要在androidMainfest.xml注册一下目标的activity

还要在

src/空间里新建一个目标的类

res/layout/目录下新建一个对应的布局文件xml。

具体源码：

TestActivity.JAVA

package vc.com;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class TestActivity extends Activity {
/** Called when the activity is first created. */

Button bt;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
bt=(Button)findViewById(R.id.bt1);
final EditText et1=(EditText)findViewById(R.id.un);
final EditText et2=(EditText)findViewById(R.id.pwd);
final Builder al=new AlertDialog.Builder(this);

bt.setOnClickListener(new Button.OnClickListener(){

public void onClick(View v) {
// TODO Auto-generated method stub
if(et1.getText().length()==0 || et1.getText()==null)
{ al.setTitle("错误信息");
al.setMessage("提交内容不能为空！");
al.setCancelable(true);
al.setPositiveButton("确定", new DialogInterface.OnClickListener() {

public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub

}
});
al.setNeutralButton("取消",null );
al.create().show();

}else{
Toast.makeText(TestActivity.this, et1.getText().toString().trim(),Toast.LENGTH_SHORT).show();
Intent intent = new Intent();
intent.setClass(TestActivity.this, login.class);
startActivity(intent);
}

}
});
}
}

//对应的xml布局

<?xml version="1.0" encoding="utf-8"?>
<AbsoluteLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:background="@drawable/bg" >

//login.java

package vc.com;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class login extends Activity {

/**
* @param args
*/

public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.mylayout);
Button b2 = (Button) findViewById(R.id.button2);

b2.setOnClickListener(new Button.OnClickListener()
{
public void onClick(View v)
{
/* newIntentclass */

Intent intent = new Intent();
intent.setClass(login.this, TestActivity.class);

/* Activity */
startActivity(intent);
/* Activity */
login.this.finish();
}
});
}
}

//对应的布局文件

<?xml version="1.0" encoding="utf-8"?>
<AbsoluteLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@drawable/ic_launcher"
xmlns:android="http://schemas.android.com/apk/res/android"
>
<Button
android:id="@+id/button2"
android:layout_width="118px"
android:layout_height="wrap_content"
android:layout_x="100px"
android:layout_y="82px"
android:text="Go to Activity1"
>
</Button>
</AbsoluteLayout>

//androidMainfest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="vc.com"
android:versionCode="1"
android:versionName="1.0" >

<uses-sdk android:minSdkVersion="3" />

</manifest>

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