屏幕间的跳转和传值

一、        代码

1.         MainActivity.java

 package com.receiveresult;

 

import android.os.Bundle;

import android.app.Activity;

import android.content.Intent;

import android.util.Log;

import android.view.View;

import android.widget.Button;

import android.widget.TextView;

 

publicclass MainActivity extends Activity {

 

    staticfinalprivateintGET_CODE = 0;

   

    @Override

    protectedvoid onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

       

        Button button = (Button)findViewById(R.id.button1);

       

        button.setOnClickListener(new Button.OnClickListener(){

            publicvoid onClick(View v){

             Intent intent = new Intent();

             intent.setClass(MainActivity.this,ReceiverActivity.class);

             startActivityForResult(intent, GET_CODE);

         }

        });

       

        Log.v("MainActivity", "onCreate");

    }

   

    /**

     * requestCode就是startActivityForResult的requestCode，resultCode就是setResult里面的resultCode，返回的数据在data里面。

     */

    @Override

  protectedvoid onActivityResult(int requestCode, int resultCode, Intent data) {

      if (requestCode == GET_CODE) {

          TextView text = (TextView) findViewById(R.id.textView1);

          if (resultCode == RESULT_CANCELED) {

              text.setText("cancelled");

          } else {

              if (data != null) {

                  text.setText(data.getAction());

              }

          }

      }

      Log.v("MainActivity", "onActivityResult");

  }

 

}

 

2.   ReceiverActivity.java

 package com.receiveresult;

 

import android.app.Activity;

import android.content.Intent;

import android.os.Bundle;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

 

publicclass ReceiverActivity extends Activity {

   

    @Override

    protectedvoid onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.receiver_main);

        Button ok = (Button)findViewById(R.id.ok);

        ok.setOnClickListener(okListener);

       

        Button fail = (Button)findViewById(R.id.fail);

        fail.setOnClickListener(failListener);

    }

 

    private OnClickListener okListener = new OnClickListener() {

        publicvoid onClick(View v) {

            setResult(RESULT_OK, new Intent().setAction("ok!"));

            //要调用finish()销毁当前的Activity，否则无法返回到原来的Activity

            finish();

        }

    };

    private OnClickListener failListener = new OnClickListener() {

        publicvoid onClick(View v) {

            setResult(RESULT_OK, new Intent().setAction("fail!"));

            //要调用finish()销毁当前的Activity，否则无法返回到原来的Activity

            finish();

        }

    };

   

}

 

3.   activity_main.xml

 <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=".MainActivity" >

 

    <TextView

        android:id="@+id/textView1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_alignLeft="@+id/button1"

        android:layout_alignParentTop="true"

        android:layout_marginTop="26dp"

        android:text="" />

 

    <Button

        android:id="@+id/button1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_below="@+id/textView1"

        android:layout_centerHorizontal="true"

        android:layout_marginTop="50dp"

        android:text="@string/go" />

 

</RelativeLayout>

4.   receiver_main.xml

 <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=".MainActivity" >

 

    <Button

        android:id="@+id/ok"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_alignParentTop="true"

        android:layout_centerHorizontal="true"

        android:layout_marginTop="76dp"

        android:text="@string/ok" />

 

    <Button

        android:id="@+id/fail"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_alignLeft="@+id/ok"

        android:layout_below="@+id/ok"

        android:layout_marginTop="38dp"

        android:text="@string/fail" />

 

</RelativeLayout>

二、        运行结果

三、        总结

1)   Activity跳转，无返回结果。从一个Activity启动另一个Activity，直接startActivity(new Intent(当前Activity.this, 下一Activity.class))。

2)   Activity跳转，有返回结果。

    startActivityForResult（Intenet intenet,int requestCode）。

3)   Activity传送数据：

intent.putExtra("Text", mText);

 

Bundle extras = getIntent().getExtras();

String text = extras.getString("Text");