第五集android使用全局變量傳遞數據

安下圖新建出

MainActivity.java

Mapp.java

OtherActivity.java

main.xml

other.xml

MainActivity.java

 1 package com.fxp.app;
 2 
 3 import android.os.Bundle;
 4 import android.app.Activity;
 5 import android.content.Intent;
 6 import android.view.Menu;
 7 import android.view.View;
 8 import android.view.View.OnClickListener;
 9 import android.widget.Button;
10 import android.widget.TextView;
11 
12 public class MainActivity extends Activity {
13     private Button gobutton;
14     private TextView firstTextView;
15     private Mapp mapp;
16 
17     @Override
18     protected void onCreate(Bundle savedInstanceState) {
19         super.onCreate(savedInstanceState);
20         setContentView(R.layout.main);
21         gobutton = (Button) findViewById(R.id.goButton);
22         firstTextView = (TextView) findViewById(R.id.firstTextView);
23         mapp = (Mapp) getApplication();
24         
25         firstTextView.setText(mapp.getName());
26         GoButtonListener goButtonListener = new GoButtonListener();
27         gobutton.setOnClickListener(goButtonListener);
28     }
29     class GoButtonListener implements OnClickListener{
30         @Override
31         public void onClick(View v) {
32             mapp.setName("張三");
33             Intent intent=new Intent();
34             intent.setClass(MainActivity.this, OtherActivity.class);
35             startActivity(intent);
36         }
37     }
38 
39     @Override
40     public boolean onCreateOptionsMenu(Menu menu) {
41         // Inflate the menu; this adds items to the action bar if it is present.
42         getMenuInflater().inflate(R.menu.main, menu);
43         return true;
44     }
45 
46 }

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Mapp.java

 1 package com.fxp.app;
 2 
 3 import android.app.Application;
 4 
 5 public class Mapp extends Application {
 6     private String name;
 7 
 8     public String getName() {
 9         return name;
10     }
11 
12     public void setName(String name) {
13         this.name = name;
14     }
15 
16     @Override
17     public void onCreate() {
18         super.onCreate();
19         setName("jack");
20     }
21     
22 }

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OtherActivity.java

 1 package com.fxp.app;
 2 
 3 import android.app.Activity;
 4 import android.content.Intent;
 5 import android.os.Bundle;
 6 import android.view.View;
 7 import android.view.View.OnClickListener;
 8 import android.widget.Button;
 9 import android.widget.TextView;
10 
11 public class OtherActivity extends Activity {
12     private Button backButton;
13     private TextView secondTextView;
14     private Mapp mapp;
15 
16     @Override
17     protected void onCreate(Bundle savedInstanceState) {
18         super.onCreate(savedInstanceState);
19         setContentView(R.layout.other);
20         backButton = (Button) findViewById(R.id.backButton);
21         secondTextView = (TextView) findViewById(R.id.secondTextView);
22         mapp = (Mapp) getApplication();
23 
24         secondTextView.setText(mapp.getName());
25         BackButtonListener backButtonListener = new BackButtonListener();
26         backButton.setOnClickListener(backButtonListener);
27     }
28 
29     class BackButtonListener implements OnClickListener {
30         @Override
31         public void onClick(View v) {
32             mapp.setName("李四回到第一頁");
33             Intent intent = new Intent();
34             intent.setClass(OtherActivity.this, MainActivity.class);
35             startActivity(intent);
36         }
37     }
38 }

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main.xml

 1 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     xmlns:tools="http://schemas.android.com/tools"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:paddingBottom="@dimen/activity_vertical_margin"
 6     android:paddingLeft="@dimen/activity_horizontal_margin"
 7     android:paddingRight="@dimen/activity_horizontal_margin"
 8     android:paddingTop="@dimen/activity_vertical_margin"
 9     tools:context=".MainActivity" >
10 
11     <TextView
12         android:id="@+id/firstTextView"
13         android:layout_width="wrap_content"
14         android:layout_height="wrap_content"
15         android:text="開始" />
16     <Button
17         android:id="@+id/goButton"
18         android:layout_width="wrap_content"
19         android:layout_height="wrap_content"
20         android:layout_below="@id/firstTextView"
21         android:text="跳第二頁" />
22 </RelativeLayout>

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other.xml

 1 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     xmlns:tools="http://schemas.android.com/tools"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:paddingBottom="@dimen/activity_vertical_margin"
 6     android:paddingLeft="@dimen/activity_horizontal_margin"
 7     android:paddingRight="@dimen/activity_horizontal_margin"
 8     android:paddingTop="@dimen/activity_vertical_margin"
 9     tools:context=".MainActivity" >
10 
11     <TextView
12         android:id="@+id/secondTextView"
13         android:layout_width="wrap_content"
14         android:layout_height="wrap_content"
15         android:text="開始" />
16     <Button
17         android:id="@+id/backButton"
18         android:layout_width="wrap_content"
19         android:layout_height="wrap_content"
20         android:layout_below="@id/secondTextView"
21         android:text="跳第一頁" />
22 </RelativeLayout>

View Code